How can I find a maximum mean value of row with given 2D array?

Question

minsoo kim 2017-12-3

回答： Star Strider 2017-12-3

Let's say I have a 2D array S(m,n).

What I want to do is to find a row that has the biggest mean value. I'll call this row as 'i'th row.

So my matlab code was like this.

[i]=find(S==max(mean(S)));
[i]

But matlab just shows "ans = []" which means, there is something wrong with my code.

The problem is, I have no idea how to fix it.

Someone said that

maxRow=find(max(mean(S,2)));
i = maxRow

this code could solve the problem but unfortunately, the code above only returns 1.

Any ideas?

Answer 1

Star Strider 2017-12-3

Try this:

max_mean_row_idx = find(mean(S,2) == max(mean(S,2)))
max_mean_row = mean(S(max_mean_row_idx,:),2)

if there could be several rows with the same maximum row mean,

or:

[max_mean_row,max_mean_row_idx] = max(mean(S,2))

if you only want the first maximum row mean.