# Help in writing a a code for an array based on comdition.

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Haya Ali on 17 Mar 2023
Commented: Walter Roberson on 17 Mar 2023
I have an array A. A1= [-0.0082 -0.0409 -0.0175 -0.0853 0.0217 -0.2556 -0.0302 0 ]
From A array I want to replace negative numbers with -1, positive numbers with 1 and zero will remain zero . Like this :
A= [-1 -1 -1 -1 1 -1 -1 0]
Then I want to take there sum and if there sum is smaller than threshold then value will be set to zero. If equals and greater than threshold than value will be 1. Threshold is 12.
How to write code for this?

Torsten on 17 Mar 2023
A1 = [-0.0082 -0.0409 -0.0175 -0.0853 0.0217 -0.2556 -0.0302]
A1 = 1×7
-0.0082 -0.0409 -0.0175 -0.0853 0.0217 -0.2556 -0.0302
A = -(A1<0) + (A1>0)
A = 1×7
-1 -1 -1 -1 1 -1 -1
s = sum(A)
s = -5
threshold = 12;
value = double(s >= threshold)
value = 0
Haya Ali on 17 Mar 2023
Edited: Haya Ali on 17 Mar 2023
Columns 1 through 13
0.0000 -0.0000 3.2115 2.7009 -0.0000 -0.0000 0.0000 0.1799 0.9524 -0.0000 -0.0000 0.1566 0.0000
Columns 14 through 25
-0.0000 -0.0000 -0.0000 -0.0000 -0.0000 0.0000 -0.0000 0.0000 -0.0000 0.0000 -0.0000 -0.0000
A =
Columns 1 through 21
1 -1 1 1 -1 -1 1 1 1 -1 -1 1 1 -1 -1 -1 -1 -1 1 -1 1
Columns 22 through 25
-1 1 -1 -1
Walter Roberson on 17 Mar 2023
0 and -0 display as 0 not as 0.0000 or -0.0000. So your values are not 0 and -0
Give the command
format long g
and then display your values again

Walter Roberson on 17 Mar 2023
See sum sign
However, your description does not match your example. You say you want to replace positive numbers with 1, but your example shows replacing the only positive number with 0.
Haya Ali on 17 Mar 2023
My mistake.