Mercurial > repos > public > sbplib
changeset 1185:abb1b3ab8c23 feature/rv
Fix incorrect of RungekuttaRvInstage
| author | Vidar Stiernström <vidar.stiernstrom@it.uu.se> |
|---|---|
| date | Fri, 05 Jul 2019 18:12:10 +0200 |
| parents | ecc605453733 |
| children | 3364a51f0d9e |
| files | +rv/+time/RungeKuttaRvInstage.m +rv/+time/RungekuttaRvInstage.m |
| diffstat | 2 files changed, 79 insertions(+), 79 deletions(-) [+] |
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--- a/+rv/+time/RungeKuttaRvInstage.m Fri Jul 05 17:51:11 2019 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,79 +0,0 @@ -classdef RungekuttaRvInstage < time.Timestepper - properties - F % RHS of the ODE - k % Time step - t % Time point - v % Solution vector - n % Time level - coeffs % The coefficents used for the RK time integration - RV % Residual Viscosity - DvDt % Function for computing the time deriative used for the RV evaluation - end - - methods - function obj = RungekuttaRvInstage(F, k, t0, v0, RV, DvDt, order) - obj.F = F; - obj.k = k; - obj.t = t0; - obj.v = v0; - obj.n = 0; - % Extract the coefficients for the specified order - % used for the RK updates from the Butcher tableua. - [s,a,b,c] = time.rk.butcherTableau(order); - obj.coeffs = struct('s',s,'a',a,'b',b,'c',c); - obj.RV = RV; - obj.DvDt = DvDt; - end - - function [v, t] = getV(obj) - v = obj.v; - t = obj.t; - end - - function state = getState(obj) - dvdt = obj.DvDt(obj.v); - [viscosity, Df, firstOrderViscosity, residualViscosity] = obj.RV.evaluate(obj.v, dvdt); - state = struct('v', obj.v, 'dvdt', dvdt, 'Df', Df, 'viscosity', viscosity, 'residualViscosity', residualViscosity, 'firstOrderViscosity', firstOrderViscosity, 't', obj.t); - end - - % Advances the solution vector one time step using the Runge-Kutta method given by - % obj.coeffs, updating the Residual Viscosity in each Runge-Kutta stage - function obj = step(obj) - obj.v = rv.time.rungekuttaRV(obj.v, obj.t, obj.k, obj.F, obj.RV, obj.DvDt, obj.coeffs); - obj.t = obj.t + obj.k; - obj.n = obj.n + 1; - end - end - - % Takes one time step of size dt using the rungekutta method - % starting from v and where the function F(v,t,RV) gives the - % time derivatives. coeffs is a struct holding the RK coefficients - % for the specific method. RV is the residual viscosity which is updated - % in between the stages and after the updated solution is computed. - methods (Static) - function v = rungekuttaRV(v, t , dt, F, RV, DvDt, coeffs) - % Move one stage outside to avoid branching for updating the - % residual inside the loop. - k = zeros(length(v), coeffs.s); - k(:,1) = F(v,t,RV.evaluateViscosity(v,DvDt(v))); - - % Compute the intermediate stages k - for i = 2:coeffs.s - u = v; - for j = 1:i-1 - u = u + dt*coeffs.a(i,j)*k(:,j); - end - k(:,i) = F(u,t+coeffs.c(i)*dt, RV.evaluateViscosity(u,DvDt(u))); - end - - % Compute the updated solution as a linear combination - % of the intermediate stages. - u = v; - for i = 1:coeffs.s - u = u + dt*coeffs.b(i)*k(:,i); - end - v = u; - end - - -end \ No newline at end of file
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/+rv/+time/RungekuttaRvInstage.m Fri Jul 05 18:12:10 2019 +0200 @@ -0,0 +1,79 @@ +classdef RungekuttaRvInstage < time.Timestepper + properties + F % RHS of the ODE + k % Time step + t % Time point + v % Solution vector + n % Time level + coeffs % The coefficents used for the RK time integration + RV % Residual Viscosity + DvDt % Function for computing the time deriative used for the RV evaluation + end + + methods + function obj = RungekuttaRvInstage(F, k, t0, v0, RV, DvDt, order) + obj.F = F; + obj.k = k; + obj.t = t0; + obj.v = v0; + obj.n = 0; + % Extract the coefficients for the specified order + % used for the RK updates from the Butcher tableua. + [s,a,b,c] = time.rk.butcherTableau(order); + obj.coeffs = struct('s',s,'a',a,'b',b,'c',c); + obj.RV = RV; + obj.DvDt = DvDt; + end + + function [v, t] = getV(obj) + v = obj.v; + t = obj.t; + end + + function state = getState(obj) + dvdt = obj.DvDt(obj.v); + [viscosity, Df, firstOrderViscosity, residualViscosity] = obj.RV.evaluate(obj.v, dvdt); + state = struct('v', obj.v, 'dvdt', dvdt, 'Df', Df, 'viscosity', viscosity, 'residualViscosity', residualViscosity, 'firstOrderViscosity', firstOrderViscosity, 't', obj.t); + end + + % Advances the solution vector one time step using the Runge-Kutta method given by + % obj.coeffs, updating the Residual Viscosity in each Runge-Kutta stage + function obj = step(obj) + obj.v = rv.time.rungekuttaRV(obj.v, obj.t, obj.k, obj.F, obj.RV, obj.DvDt, obj.coeffs); + obj.t = obj.t + obj.k; + obj.n = obj.n + 1; + end + end + + % Takes one time step of size dt using the rungekutta method + % starting from v and where the function F(v,t,RV) gives the + % time derivatives. coeffs is a struct holding the RK coefficients + % for the specific method. RV is the residual viscosity which is updated + % in between the stages and after the updated solution is computed. + methods (Static) + function v = rungekuttaRV(v, t , dt, F, RV, DvDt, coeffs) + % Move one stage outside to avoid branching for updating the + % residual inside the loop. + k = zeros(length(v), coeffs.s); + k(:,1) = F(v,t,RV.evaluateViscosity(v,DvDt(v))); + + % Compute the intermediate stages k + for i = 2:coeffs.s + u = v; + for j = 1:i-1 + u = u + dt*coeffs.a(i,j)*k(:,j); + end + k(:,i) = F(u,t+coeffs.c(i)*dt, RV.evaluateViscosity(u,DvDt(u))); + end + + % Compute the updated solution as a linear combination + % of the intermediate stages. + u = v; + for i = 1:coeffs.s + u = u + dt*coeffs.b(i)*k(:,i); + end + v = u; + end + + +end \ No newline at end of file