annotate mononomial.m @ 1198:2924b3a9b921 feature/d2_compatible

Add OpSet for fully compatible D2Variable, created from regular D2Variable by replacing d1 by first row of D1. Formal reduction by one order of accuracy at the boundary point.
author Martin Almquist <malmquist@stanford.edu>
date Fri, 16 Aug 2019 14:30:28 -0700
parents 0090a86d8b72
children
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0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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1 % calculate a N-D mononomial with powers k in points x:
0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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2 % z = x(:,1).^k(1) * x(:,2).^k(2) * ...
0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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3 function z = mononomial(x, k)
0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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4 assert(size(x,2) == length(k), 'k must have the same length as the width of x');
0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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5
0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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6 if any(k < 0)
0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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7 z = x(:,1)*0;
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184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
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8 return
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
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9 end
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0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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11 denom = prod(factorial(k));
0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
diff changeset
13 for i = 1:length(k)
0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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14 x(:,i) = x(:,i).^k(i);
0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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15 end
0090a86d8b72 Improve mononomial and vandermonde functions to work in multiple dimension and adapt to sym or double inputs
Jonatan Werpers <jonatan@werpers.com>
parents: 660
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16 z = prod(x,2)/denom;
660
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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17 end