Why is this function returning the wrong size matrix

1 次查看（过去 30 天）

Ali 2013-3-30

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/69159-why-is-this-function-returning-the-wrong-size-matrix

I wrote a very simple function to calculate stock price return regardless of the number of companies listed in the array. The company stock prices are listed in separate columns. The function code is:

function percentReturn=retCalc(prices)
percentReturn=prices(1:end-1,:)./prices(2:end,:)-1;

I would assume that this function should calculate the return regardless of the number of columns in the matrix. However, it just returns the first column of return. Can someone please tell me what I'm doing wrong?

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Cedric 2013-3-30

编辑：Cedric 2013-3-30

在 MATLAB Online 中打开

Did you check that the local variable prices has really the correct size? If you add the line

size(prices)

right before the line computing percentReturn, you might see that prices doesn't have as many columns (companies) as what you think. Well, reading again your statement .. the way you perform your computation suggests that there is one company per column, and therefore that prices vary along rows, which is not what you seem to indicate above.

请先登录，再进行评论。

请先登录，再回答此问题。