We have a MxN matrix and a constrain cstrn = 100;.
The constrain is the summarize limit of column's elements (per column):
sum(matrix(:,:))<=cstrn.
For a given example as the following:
Columns 1 to 5:
15 18 -5 22 19
50 98 -15 39 -8
70 -15 80 45 38
31 52 9 80 72
-2 63 52 71 6
7 99 32 58 41
I want to find the max number of element per column who fulfill this constrain.
How can i summarize every column element with the others elements in same column and find which sum combinations uses the max number of elements per column?
In the given example solution is:
4 3 5 2 5
where
column 1: 15 + 50 + 31 +7 +(-2)
column 2: 18 +(-15) + 52 or 63 etc.
Thank you in advance.
Since it is always easier to fit small elements into a sum, you can do a sort, followed by the cumulative sum:
m= [
15 18 -5 22 19
50 98 -15 39 -8
70 -15 80 45 38
31 52 9 80 72
-2 63 52 71 6
7 99 32 58 41];
cs = cumsum(sort(m))
cs =
-2 -15 -15 22 -8
5 3 -20 61 -2
20 55 -11 106 17
51 118 21 164 55
101 216 73 235 96
171 315 153 315 168
Now you easily identify at which element you cross the threshold cnstrn (thanks, @sevenless)!
out = sum(cs <= cnstrn)
out =
4 3 5 2 5