Defining functions with exponentials

Question

Honey Adams 2018-7-13

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/410207-defining-functions-with-exponentials

评论： Honey Adams 2018-7-13

Cummulative_sales.PNG

I defined the function below in Matlab where my parameters are x and constants v, data, t. I tried to test the function but the function generates errors relating to the exponents. Attached is an image of the function. P*m*((1-e^(-(p+(q_m q_0)/(q_(0+) (q_m-q_0)e^(-vw) ))*t)))/(P+ ((q_m q_0)/(q_(0+) (q_m-q_0)e^(-vw) ))*e^(-(P+ ((q_m q_0)/(q_(0+) (q_m-q_0 ) e^(-vw) ))*t) )

function res= Bass(x,v,data ,t)

%objective function
F=[-data + (x(1)*x(2)*((1- exp*(-x(1)-((x(3)*x(4))/(x(4)+(x(3)-x(4))*exp(-x(5)*v))))*t)/...
    (x(1) + ((x(3)*x(4)) / (x(4)+((x(3)-x(4))*exp(-x(5)*v)))) * exp(-x(1) - ((x(3)*x(4)) /( x(4)+(x(3)-x(4))*exp(-x(5)*v))))*t)))];
   res=sum(F.^2)

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Florian Floh 2018-7-13

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/410207-defining-functions-with-exponentials#answer_328701

In the very first line of your code, you misplaced the '*' (you placed it right after the 'exp' expression. I tried the following code by myself and it worked flawlessly. I hope my answer was helpful.

% This one should work:

F=[-data + (x(1)*x(2)*((1- exp((-x(1)-((x(3)*x(4))/(x(4)+(x(3)-x(4))*exp(-x(5)*v))))*t))/... (x(1) + ((x(3)*x(4)) / (x(4)+((x(3)-x(4))*exp((-x(5)*v)))) * exp(-x(1) - ((x(3)*x(4))) /( x(4)+(x(3)-x(4))*exp((-x(5)*v))))*t))))]; res=sum(F.^2)