Error in MuPAD command: The dimensions do not match

1 次查看（过去 30 天）
PIERLUIGI PEDERZOLI
回答： PIERLUIGI PEDERZOLI 2015-7-21
Hi, I have to do a for cicle in which one variable (k) change and the others variables are costants, but Matlab gives me an error: Error in MuPAD command: The dimensions do not match. I am trying to use the following code (I'm sorry for the length of the equation) to obtain a vectors of results. Then I want to plot KAP as function of k:
syms F x c k
KAP=(F*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - k*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - k^2*exp(-k*(F + c - x))*(F*exp(-x) - 1) - F*exp(-k*(F + c - x))*exp(-x) + 2*F*k*exp(-k*(F + c - x))*exp(-x) + F*k^2*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1)^2 + 2*F*k*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1))/(k*exp(-k*(F + c - x))*(F*exp(-x) - 1) + F*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - F*exp(-k*(F + c - x))*exp(-x) + F*k*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1))
k=0.1:0.1:0.6
for i=1:length(k)
KAP=(F*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - k*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - k^2*exp(-k*(F + c - x))*(F*exp(-x) - 1) - F*exp(-k*(F + c - x))*exp(-x) + 2*F*k*exp(-k*(F + c - x))*exp(-x) + F*k^2*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1)^2 + 2*F*k*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1))/(k*exp(-k*(F + c - x))*(F*exp(-x) - 1) + F*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - F*exp(-k*(F + c - x))*exp(-x) + F*k*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1))
KAP=subs(KAP,{F,x,c,k(i)},{5,4,4,0.1})
KAP=vpa(KAP)
end
Variables like F, x, c have to be constant. Anyone could help me?

请先登录，再回答此问题。

回答（3 个）

Walter Roberson
Walter Roberson 2015-7-20
syms F x c k
KAPeqn = (F*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - k*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - k^2*exp(-k*(F + c - x))*(F*exp(-x) - 1) - F*exp(-k*(F + c - x))*exp(-x) + 2*F*k*exp(-k*(F + c - x))*exp(-x) + F*k^2*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1)^2 + 2*F*k*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1))/(k*exp(-k*(F + c - x))*(F*exp(-x) - 1) + F*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - F*exp(-k*(F + c - x))*exp(-x) + F*k*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1));
kvals = 0.1:0.1:0.6;
for i = 1 : length(kvals)
KAP(i) = vpa(subs(KAPeqn,{F,x,c,k},{5,4,4,kvals(i)}));
end
plot(kvals, KAP);
PIERLUIGI PEDERZOLI
Thanks a lot. Now it works well. How can I see all the steps of the scripts in the command window with the numeric value that KAPeqn assumes when k change?
  1 个评论
Walter Roberson
Walter Roberson 2015-7-20
syms F x c k
KAPeqn = (F*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - k*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - k^2*exp(-k*(F + c - x))*(F*exp(-x) - 1) - F*exp(-k*(F + c - x))*exp(-x) + 2*F*k*exp(-k*(F + c - x))*exp(-x) + F*k^2*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1)^2 + 2*F*k*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1))/(k*exp(-k*(F + c - x))*(F*exp(-x) - 1) + F*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F)) - F*exp(-k*(F + c - x))*exp(-x) + F*k*exp(-x)*exp(-k*(F + c - x - (exp(F) - exp(x))/F))*(exp(x)/F - 1));
kvals = 0.1:0.1:0.6;
for i = 1 : length(kvals)
KAPi = vpa(subs(KAPeqn,{F,x,c,k},{5,4,4,kvals(i)}))
KAP(i) = KAPi;
end
plot(kvals, KAP);

请先登录，再进行评论。

PIERLUIGI PEDERZOLI
Again thank you!

类别

在 Help Center 和 File Exchange 中查找有关 Dates and Time 的更多信息

标签

Community Treasure Hunt

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

Start Hunting!

Translated by