Matlab, for loop simple division problem

[feicobain]

I put down a script like this

for u=(10:10:20)'
i=(1:size(u,1))'
X=zeros(size(u,1),1)
X(i,1)=100/u(i,1)
end

I expect to get a result like

X=
10
5

but it came out like

X=
0
5

It seems it does work if it contain / in the equation. Please help!

 

[MATLABdude]

Did you realize that i contains two elements? The syntax u(i,1) makes no sense when i contains two elements. You've either got u and i jumbled up, or I'm not understanding what you're trying to do.

You also need to initialize your variables outside the loop.

So, this is probably the code you're looking for:

u=(10:10:20)'
X=zeros(size(u,1), 1)

for i = 1:size(u,1)
X(i,1) = 100 / u(i,1)
end

Which produces the desired results.

EDIT: Ooops, forgot some parentheses...

 

[oswaler]

Thank you for sharing your script and the expected result. From a first glance, it looks like your for loop and the division operation are correct. However, the issue may lie in the way you are defining the variable "u". In your for loop, you have specified "u=(10:10:20)'", which creates a vector with only two elements (10 and 20). This means that the for loop will only iterate twice, resulting in a "X" vector with only two values.

To get the desired result, you can define "u" as a vector with more elements, such as "u=(10:10:30)'". This will create a vector with three elements (10, 20, and 30), and your for loop will iterate three times, resulting in a "X" vector with three values. Alternatively, you can also use the "size" function to dynamically determine the size of "u" and use that in your for loop, instead of specifying a fixed value.

I hope this helps and solves the issue you were facing. If you require further assistance, please let me know. Keep up the great work with your Matlab programming!