MATLAB Answers

如何将两个值归因于一个参数，以使时间依赖于时间

2 views (last 30 days)
Show older comments
Andrew Agada
Andrew Agada on 2 Sep 2021
Commented: Fabio Freschi on 2 Sep 2021
在此我的附件代码中，我想改变伽马的值，以使其取决于驱动程序中的TSPAN。
当tspan < = 7γequal to 0.001 as show in the attached code
but when tspan is >7 gamma should be equal to 1.
find attach the code and the driver used for runing the code.
谢谢

Sign in to answer this question.

答案（2）

Fabio Freschi
Fabio Freschi on 2 Sep 2021
You can pass an extra parameter to RiceG1 function using an anonmymous function. In your driver function add
% extra anonimous function to pass tspan
myfun = @(t,y)RiceG1(t,y,tspan);
% call to ode45
[b，v] = ode45（myfun，tspan，y0）;
Then modify RiceG1 to accept the extra parameter and make the choice. I write below an extract of the function
功能dy = riceg1（〜，y，tspan）
％...
iftspan(2) <= 7
gamma = 0.001;
else
γ= 1;
end
我认为必须在TSPAN（2）上进行检查。修改后的文件已连接。
Walter Roberson
Walter Roberson on 2 Sep 2021
不幸的是，法比奥的建议将行不通。当您在计算过程中更改伽马时，您会在集成的函数的导数中引入不连续性，并且当您患有这样的不连续性时，ODE45的数学变得无效。您需要停止集成并重新开始，但要以不同的伽马价值开始。
You should, however, use the technique of passing in an additional parameter -- but it should be gamma directly, not tspan.
//www.tianjin-qmedu.com/help/matlab/math/parameterizing-functions.html
Y0 = [1200 400 60 30 30 30 30 30 20 10 3000 30000];
tspan1 = [0 7];
tspan2 = [7 15];
γ1= 0.001;
gamma2 = 1;
funs = {@RiceG1, @RiceG2, @RiceG3, @RiceG4, @RiceG5};
forK = 1 : length(funs)
[t_out1，y_out1] = ode45（@（t，y）有趣{k}（t，y，gamma1），tspan1，y0）;
[t_out2, y_out2] = ode45(@(t,y)funs{K}(t,y,gamma2), tspan2, y_out1(end,:));
t_out {k} = [t_out1;t_out2];
y_out {k} = [y_out1;y__out2];
end
[B, C, D, E, F] = deal(t_out{:});
[V, W, X, Y, Z] = deal(y_out{:});
3 Comments
Show＆nbsp2旧评论

Sign in to comment.

Categories

Tags

s manbetx 845


发布

R2018A

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

开始狩猎！