sbplib_julia: Notes.md annotate

annotate Notes.md @ 718:05d8ea88c690

Add note about performance testin

author	Jonatan Werpers <jonatan@werpers.com>
date	Fri, 12 Mar 2021 19:55:39 +0100
parents	841ca12f3359
children	f88b2117dc69 d7d030f8f708

rev	line source
318 0c8d4a734c4f Add some todos and add a Notes.md file Jonatan Werpers <jonatan@werpers.com> parents: diff changeset	1 # Notes
0c8d4a734c4f Add some todos and add a Notes.md file Jonatan Werpers <jonatan@werpers.com> parents: diff changeset	2
654 d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	3 ## Reading operators
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	4
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	5 Jonatan's suggestion is to add methods to `Laplace`, `SecondDerivative` and
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	6 similar functions that take in a filename from which to read stencils. These
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	7 methods encode how to use the structure in a file to build the particular
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	8 operator. The filename should be a keyword argument and could have a default
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	9 value.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	10
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	11 * This allows easy creation of operators without the user having to handle stencils.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	12 * The user can easily switch between sets of operators by changing the file stecils are read from.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	13
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	14 Grids for optimized operators could be created by reading from a .toml file in
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	15 a similar fashion as for the operators. The grid can then be used in a
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	16 `Laplace` method which dispatches on the grid type and knows how to read the
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	17 optimized operators. The method would also make sure the operators match the
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	18 grid.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	19
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	20 Idea: Make the current upper case methods lower case. Add types with the upper
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	21 case names. These types are tensor mappings for the operator but also contain
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	22 the associated operators as fields. For example:
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	23
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	24 ```julia
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	25 L = Laplace(grid)
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	26 L.H
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	27 L.Hi
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	28 L.e
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	29 L.d
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	30 L.M
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	31
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	32 wave = L - L.Hi∘L.e'∘L.d
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	33 ```
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	34
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	35 These types could also contain things like borrowing and such.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	36
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	37 ## Storage of operators
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	38 We need to change the toml format so that it is easier to store several
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	39 operator with different kinds of differentiations. For example there could be
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	40 several operators of the same order but with different number of boundary
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	41 points or different choice of boundary stencils.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	42
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	43 Properties that differentiate operators should for this reason be stored in
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	44 variables and not be section or table names.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	45
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	46 Operators/sets of stencils should be stored in an [array of tables](https://toml.io/en/v1.0.0-rc.3#array-of-tables).
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	47
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	48 We should formalize the format and write simple and general access methods for
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	49 getting operators/sets of stencils from the file. They should support a simple
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	50 way to filter based on values of variables. There filters could possibly be
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	51 implemented through keyword arguments that are sent through all the layers of
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	52 operator creation.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	53
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	54 * Remove order as a table name and put it as a variable.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	55
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	56
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	57 ## Variable second derivative
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	58
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	59 2020-12-08 after discussion with Vidar:
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	60 We will have to handle the variable second derivative in a new variant of
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	61 VolumeOperator, "SecondDerivativeVariable?". Somehow it needs to know about
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	62 the coefficients. They should be provided as an AbstractVector. Where they are
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	63 provided is another question. It could be that you provide a reference to the
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	64 array to the constructor of SecondDerivativeVariable. If that array is mutable
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	65 you are free to change it whenever and the changes should propagate
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	66 accordingly. Another option is that the counter part to "Laplace" for this
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	67 variable second derivate returns a function or acts like a functions that
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	68 takes an Abstract array and returns a SecondDerivativeVariable with the
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	69 appropriate array. This would allow syntax like `D2(a)*v`. Can this be made
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	70 performant?
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	71
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	72 For the 1d case we can have a constructor
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	73 `SecondDerivativeVariable(D2::SecondDerivativeVariable, a)` that just creates
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	74 a copy with a different `a`.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	75
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	76 Apart from just the second derivative in 1D we need operators for higher
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	77 dimensions. What happens if a=a(x,y)? Maybe this can be solved orthogonally to
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	78 the `D2(a)*v` issue, meaning that if a constant nD version of
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	79 SecondDerivativeVariable is available then maybe it can be wrapped to support
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	80 function like syntax. We might have to implement `SecondDerivativeVariable`
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	81 for N dimensions which takes a N dimensional a. If this could be easily
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	82 closured to allow D(a) syntax we would have come a long way.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	83
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	84 For `Laplace` which might use a variable D2 if it is on a curvilinear grid we
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	85 might want to choose how to calculate the metric coefficients. They could be
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	86 known on closed form, they could be calculated from the grid coordinates or
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	87 they could be provided as a vector. Which way you want to do it might change
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	88 depending on for example if you are memory bound or compute bound. This choice
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	89 cannot be done on the grid since the grid shouldn't care about the computer
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	90 architecture. The most sensible option seems to be to have an argument to the
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	91 `Laplace` function which controls how the coefficients are gotten from the
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	92 grid. The argument could for example be a function which is to be applied to
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	93 the grid.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	94
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	95 What happens if the grid or the varible coefficient is dependent on time?
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	96 Maybe it becomes important to support `D(a)` or even `D(t,a)` syntax in a more
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	97 general way.
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	98
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	99 ```
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	100 g = TimeDependentGrid()
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	101 L = Laplace(g)
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	102 function Laplace(g::TimeDependentGrid)
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	103 g_logical = logical(g) # g_logical is time independent
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	104 ... Build a L(a) assuming we can do that ...
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	105 a(t) = metric_coeffs(g,t)
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	106 return t->L(a(t))
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	107 end
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	108 ```
d26231227b89 Add a bunch of notes on reading and storing operators and how to implement variable second derivatives Jonatan Werpers <jonatan@werpers.com> parents: 606 diff changeset	109
318 0c8d4a734c4f Add some todos and add a Notes.md file Jonatan Werpers <jonatan@werpers.com> parents: diff changeset	110 ## Known size of range and domain?
320 d705b397aa33 Clean up Notes.md and TODO.md Jonatan Werpers <jonatan@werpers.com> parents: 319 diff changeset	111 Is there any reason to use a trait to differentiate between fixed size and unknown size?
d705b397aa33 Clean up Notes.md and TODO.md Jonatan Werpers <jonatan@werpers.com> parents: 319 diff changeset	112
379 de4746d6d126 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 332 diff changeset	113 When do we need to know the size of the range and domain?
de4746d6d126 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 332 diff changeset	114 * When indexing to provide boundschecking?
de4746d6d126 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 332 diff changeset	115 * When doing specialised computations for different parts of the range/domain?
de4746d6d126 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 332 diff changeset	116 * More?
319 05ac7d7f9176 Move research and thinking from TODO.md to Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 318 diff changeset	117
379 de4746d6d126 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 332 diff changeset	118 Maybe if we should have dynamic sizing it could be only for the range. `domain_size` would not be implemented. And the `range_size` would be a function of a vector that the TensorMapping is applied to.
332 535f1bff4bcc Add some notes and some todos Jonatan Werpers <jonatan@werpers.com> parents: 320 diff changeset	119
319 05ac7d7f9176 Move research and thinking from TODO.md to Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 318 diff changeset	120 ## Reasearch and thinking
05ac7d7f9176 Move research and thinking from TODO.md to Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 318 diff changeset	121 - [ ] Use a trait to indicate that a TensorMapping har the same range and domain?
05ac7d7f9176 Move research and thinking from TODO.md to Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 318 diff changeset	122 - [ ] Rename all the Tensor stuff to just LazyOperator, LazyApplication and so on?
05ac7d7f9176 Move research and thinking from TODO.md to Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 318 diff changeset	123 - [ ] Check how the native julia doc generator works
05ac7d7f9176 Move research and thinking from TODO.md to Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 318 diff changeset	124 - [ ] Check if Vidars design docs fit in there
05ac7d7f9176 Move research and thinking from TODO.md to Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 318 diff changeset	125 - [ ] Create a macro @lazy which replaces a binary op (+,-) by its lazy equivalent? Would be a neat way to indicate which evaluations are lazy without cluttering/confusing with special characters.
05ac7d7f9176 Move research and thinking from TODO.md to Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 318 diff changeset	126 - [ ] Specificera operatorer i TOML eller något liknande?
05ac7d7f9176 Move research and thinking from TODO.md to Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 318 diff changeset	127 H.. H_gamma etc.)
606 8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	128 - [ ] Dispatch on Lower() instead of the type Lower so `::Lower` instead of `::Type{Lower}` ???
332 535f1bff4bcc Add some notes and some todos Jonatan Werpers <jonatan@werpers.com> parents: 320 diff changeset	129 Seems better unless there is some specific reason to use the type instead of the value.
379 de4746d6d126 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 332 diff changeset	130 - [ ] How do we handle mixes of periodic and non-periodic grids? Seems it should be supported on the grid level and on the 1d operator level. Between there it should be transparent.
de4746d6d126 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 332 diff changeset	131 - [ ] Can we have a trait to tell if a TensorMapping is transposable?
de4746d6d126 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 332 diff changeset	132 - [ ] Is it ok to have "Constructors" for abstract types which create subtypes? For example a Grids() functions that gives different kind of grids based on input?
410 26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	133
606 8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	134 ## Regions and tensormappings
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	135 - [ ] Use a trait to indicate if a TensorMapping uses indices with regions.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	136 The default should be that they do NOT.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	137 - [ ] What to name this trait? Can we call it IndexStyle but not export it to avoid conflicts with Base.IndexStyle?
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	138 - [ ] Figure out repeated application of regioned TensorMappings. Maybe an instance of a tensor mapping needs to know the exact size of the range and domain for this to work?
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	139
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	140 ## Boundschecking and dimension checking
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	141 Does it make sense to have boundschecking only in getindex methods?
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	142 This would mean no bounds checking in applys, however any indexing that they do would be boundschecked. The only loss would be readability of errors. But users aren't really supposed to call apply directly anyway.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	143
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	144 Preferably dimensions and sizes should be checked when lazy objects are created, for example TensorApplication, TensorComposition and so on. If dimension checks decreases performance we can make them skippable later.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	145
410 26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	146 ## Vector valued grid functions
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	147 Från slack konversation:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	148
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	149 Jonatan Werpers:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	150 Med vektorvärda gridfunktioner vill vi ju fortfarande att grid funktionen ska vara till exempel AbstractArray{LitenVektor,2}
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	151 Och att man ska kunna göra allt man vill med LitenVektor
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	152 typ addera, jämföra osv
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	153 Och då borde points returnera AbstractArray{LitenVektor{Float,2},2} för ett 2d nät
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	154 Men det kanske bara ska vara Static arrays?
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	155
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	156 Vidar Stiernström:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	157 Ja, jag vet inte riktigt vad som är en rimlig representation
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	158 Du menar en vektor av static arrays då?
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	159
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	160 Jonatan Werpers:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	161 Ja, att LitenVektor är en StaticArray
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	162
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	163 Vidar Stiernström:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	164 Tuplar känns typ rätt inuitivt för att representera värdet i en punkt
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	165 men
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	166 det suger att man inte har + och - för dem
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	167
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	168 Jonatan Werpers:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	169 Ja precis
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	170
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	171 Vidar Stiernström:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	172 så kanske är bra med static arrays i detta fall
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	173
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	174 Jonatan Werpers:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	175 Man vill ju kunna köra en Operator rakt på och vara klar eller?
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	176
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	177 Vidar Stiernström:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	178 Har inte alls tänkt på hur det vi gör funkar mot vektorvärda funktioner
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	179 men känns som staticarrays är hur man vill göra det
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	180 tuplar är ju immutable också
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	181 blir jobbigt om man bara agerar på en komponent då
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	182
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	183 Jonatan Werpers:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	184 Hm…
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	185 Tål att tänkas på
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	186 Men det lär ju bli mer indirektion med mutables eller?
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	187 Hur fungerar det?
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	188 Det finns ju hur som helst både SVector och MVector i StaticArrays
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	189
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	190 Vidar Stiernström:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	191 När vi jobbat i c/c++ och kollat runt lite hur man brukar göra så lagrar man i princip alla sina obekanta i en lång vektor och så får man specificera i funktioerna vilken komponent man agerar på och till vilken man skriver
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	192 så man lagrar grejer enl: w = [u1, v1, u2, v2, …] i 1D.
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	193 Men alltså har ingen aning hur julia hanterar detta
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	194
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	195 Jonatan Werpers:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	196 Det vi är ute efter kanske är att en grid funcktion är en AbstractArray{T,2} where T<:NågotSomViKanRäknaMed
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	197 Och så får den typen var lite vad som helst.
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	198
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	199 Vidar Stiernström:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	200 Tror det kan vara farligt att ha nåt som är AbstractArray{LitenArray{NDof},Dim}
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	201 Jag gissar att det kompilatorn vill ha är en stor array med doubles
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	202
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	203 Jonatan Werpers:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	204 Och sen är det upp till den som använder grejerna att vara smart
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	205 Vill man vara trixig kan man väl då imlementera SuperHaxxorGridFunction <: AbstractArray{Array{…},2} som lagrar allt linjärt eller något sånt
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	206 Det kommer väl lösa sig när man börjar implementera vektorvärda saker
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	207 Euler nästa!
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	208 New
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	209 Vidar Stiernström:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	210 Det vore skönt att inte behöva skriva såhär varje gång man testar mot en tupel :smile: @test [gp[i]...] ≈ [p[i]...] atol=5e-13
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	211
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	212 Jonatan Werpers:
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	213 https://github.com/JuliaArrays/ArraysOfArrays.jl
26e186b565b3 Add some notes about vector valued grid functions Jonatan Werpers <jonatan@werpers.com> parents: 379 diff changeset	214 https://github.com/jw3126/Setfield.jl
423 10a67ac48d6e Add some notes Jonatan Werpers <jonatan@werpers.com> parents: 410 diff changeset	215
10a67ac48d6e Add some notes Jonatan Werpers <jonatan@werpers.com> parents: 410 diff changeset	216 ### Test-applikationer
10a67ac48d6e Add some notes Jonatan Werpers <jonatan@werpers.com> parents: 410 diff changeset	217 div och grad operationer
10a67ac48d6e Add some notes Jonatan Werpers <jonatan@werpers.com> parents: 410 diff changeset	218
606 8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	219 Enligt Wikipedia verkar det som att `∇⋅` agerar på första dimensionen av ett tensor fält och `div()` på sista.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	220 Om man generaliserar kanske `∇` i så fall bara lägger till en dimension i början.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	221
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	222 Kan vi implementera `⋅`(\cdot) så att de fungerar som man vill för både tensor-fält och tensor-operatorer?
427 1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	223
606 8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	224 Är `∇` ett tensor-fält av tensor-operatorer? Vad är ett tensor-fält i vår kod? Är det en special-fall av en tensor-mapping?
427 1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	225
606 8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	226 ### Grid-funktionen
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	227 Grid-funktionon har typen `AbstractArray{T,2} where T`.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	228 `T` kan vara lite vad som helst, tillexemel en SVector eller Array, eller tuple. TensorOperatorerna bryr sig inte om exakt vad det är, mer än att typen måste stödja de operationer som operatorn använder.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	229
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	230 En nackdel kan vara hur man ska få ut gridfunktionen för tex andra komponenten.
427 1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	231
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	232 Syntax:
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	233 ```
606 8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	234 f(x̄) = x̄
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	235 gf = evalOn(g, f)
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	236 gf[2,3] # x̄ för en viss gridpunkt
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	237 gf[2,3][2] # x̄[2] för en viss gridpunkt
427 1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	238 ```
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	239
606 8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	240 Note: Behöver bestämma om eval on skickar in `x̄` eller `x̄...` till `f`. Eller om man kan stödja båda.
427 1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	241
606 8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	242 ### Tensor operatorer
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	243 Vi kan ha tensor-operatorer som agerar på ett skalärt fält och ger ett vektorfält eller tensorfält.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	244 Vi kan också ha tensor-operatorer som agerar på ett vektorfält eller tensorfält och ger ett skalärt fält.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	245
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	246 TBD: Just nu gör `apply_transpose` antagandet att domän-typen är samma som range-typen. Det behöver vi på något sätt bryta. Ett alternativ är låta en TensorMapping ha `T_domain` och `T_range` istället för bara `T`. Känns dock lite grötigt. Ett annat alternativ skulle vara någon typ av trait för transpose? Den skulle kunna innehålla typen som transponatet agerar på? Vet inte om det fungerar dock.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	247
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	248 TBD: Vad är målet med `T`-parametern för en TensorMapping? Om vi vill kunna applicera en difference operator på vad som helst kan man inte anta att en `TensorMapping{T}` bara agerar på instanser av `T`.
427 1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	249
606 8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	250 Man kan implementera `∇` som en tensormapping som agerar på T och returnerar `StaticVector{N,T} where N`.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	251 (Man skulle eventuellt också kunna låta den agera på `StaticMatrix{N,T,D} where N` och returnera `StaticMatrix{M,T,D+1}`. Frågan är om man vinner något på det...)
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	252
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	253 Skulle kunna ha en funktion `range_type(::TensorMapping, ::Type{domain_type})`
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	254
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	255 Kanske kan man implementera `⋅(tm::TensorMapping{R,D}, v::AbstractArray{T,D})` där T är en AbstractArray, tm på något sätt har komponenter, lika många som T har element.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	256
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	257 ### Ratade alternativ:
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	258
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	259
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	260 #### 2.AbstractArray{T,2+1} where T (NOPE!)
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	261 Blir inte den här. Bryter mot alla tankar om hur grid funktioner ska fungera. Om de tillåts ha en annan dimension än nätet blir allt hemskt.
8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	262
427 1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	263 Man låter helt enkelt arrayen ha en extra dimension. En fördel är att man har en väldigt "native" typ. En nackdel kan vara att det eventuellt blir rörigt vilken dimension olika operatorer ska agera på. I värsta fall behöver vi "kroneckra in" de tillagda dimensionerna. Vektorfältets index kommer också att bli det första eftersom vi vill att de ska lagras kontinuerligt i minnet pga chachen. (Går kanske att lösa med en custom typ men då krånglar man till det för sig). En fördel skulle vara att man enkelt får ut olika komponenter.
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	264
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	265 Syntax:
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	266 ```
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	267 gf = eval_on_grid(g,f)
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	268 gf[:,2,3] # Hela vektorn för en gridpunkt
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	269 gf[2,2,3] # Andra komponenten av vektor fältet i en punkt.
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	270 gf[2,:,:] #
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	271 ```
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	272
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	273 ### Evaluering av funktioner på nät
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	274 Hur ska man skriva funktioner som evalueras på nätet? `f(x,y) = ...` eller `f(x̄) = ...`? Eller båda? Kan eval_on_grid se skillnad eller får användaren specificera?
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	275
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	276 ```
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	277 f(x,y) = [x^2, y^2]
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	278 f(x̄) = [x̄[1]^2, x̄[2]^2]
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	279 ```
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	280
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	281 Påverkas detta av hur vi förväntar oss kunna skapa lata gridfunktioner?
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	282
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	283 ### Komponenter som gridfunktioner
606 8f9b3eac128a Add a bunch of stuff to TODO.md and Notes.md Jonatan Werpers <jonatan@werpers.com> parents: 427 diff changeset	284 En viktig operation för vektor fält är att kunna få ut komponenter som grid-funktioner. Detta behöver antagligen kunna ske lazy.
427 1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	285 Det finns ett par olika lösningar:
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	286 * Implementera en egen typ av view som tar hand om detta. Eller Accessors.jl?
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	287 * Använda en TensorMapping
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	288 * Någon typ av lazy-broadcast
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	289 * En lazy array som applicerar en funktion för varje element.
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	290
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	291 Skulle vara en fördel om det är hyffsat generiskt så att en eventuell användare kan utöka det enkelt om de har någon egen exotisk typ. Eller ska man vila helt på
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	292
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	293 Syntax:
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	294 ```
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	295 gf = eval(...)
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	296 component(gf,2) # Andra komponenten av en vektor
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	297 component(gf,2,3) # (2,3) elementet av en matris
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	298 component(gf,:,2) # Andra kolumnen av en matris
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	299 @ourview gf[:,:][2]
1c41f4fd3e61 Add some notes and todos Jonatan Werpers <jonatan@werpers.com> parents: 423 diff changeset	300 ```
683 841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	301
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	302 ## Grids embedded in higher dimensions
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	303
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	304 For grids generated by asking for boundary grids for a regular grid, it would
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	305 make sense if these grids knew they were embedded in a higher dimension. They
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	306 would return coordinates in the full room. This would make sense when
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	307 drawing points for example, or when evaluating functions on the boundary.
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	308
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	309 Implementation of this is an issue that requires some thought. Adding an extra
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	310 "Embedded" type for each grid would make it easy to understand each type but
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	311 contribute to "type bloat". On the other hand adapting existing types to
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	312 handle embeddedness would complicate the now very simple grid types. Are there
841ca12f3359 Add notes about embedded grids Jonatan Werpers <jonatan@werpers.com> parents: 654 diff changeset	313 other ways of doing the implentation?
718 05d8ea88c690 Add note about performance testin Jonatan Werpers <jonatan@werpers.com> parents: 683 diff changeset	314
05d8ea88c690 Add note about performance testin Jonatan Werpers <jonatan@werpers.com> parents: 683 diff changeset	315 ## Performance measuring
05d8ea88c690 Add note about performance testin Jonatan Werpers <jonatan@werpers.com> parents: 683 diff changeset	316 We should be measuring performance early. How does our effective cpu and memory bandwidth utilization compare to peak performance?
05d8ea88c690 Add note about performance testin Jonatan Werpers <jonatan@werpers.com> parents: 683 diff changeset	317
05d8ea88c690 Add note about performance testin Jonatan Werpers <jonatan@werpers.com> parents: 683 diff changeset	318 We should make these test simple to run for any solver.
05d8ea88c690 Add note about performance testin Jonatan Werpers <jonatan@werpers.com> parents: 683 diff changeset	319
05d8ea88c690 Add note about performance testin Jonatan Werpers <jonatan@werpers.com> parents: 683 diff changeset	320 See [this talk](https://www.youtube.com/watch?v=vPsfZUqI4_0) for some simple ideas for defining effecive memory usage and some comparison with peak performance.
05d8ea88c690 Add note about performance testin Jonatan Werpers <jonatan@werpers.com> parents: 683 diff changeset	321
05d8ea88c690 Add note about performance testin Jonatan Werpers <jonatan@werpers.com> parents: 683 diff changeset	322

Mercurial > repos > public > sbplib_julia

annotate Notes.md @ 718:05d8ea88c690