How do i check a value is negative and make it into a condition?

Hi, I want to compare a value introduces in a matrix and depending on its' sign, make a condition. Is there any function or code to check if a value is negative or not?

Thanks in advance

[KALYAN ACHARJYA]

Actually what you want? You want to detect negative value.

Answer 1

[KALYAN ACHARJYA]

matrix(matrix<0)

Answer 2

[Ramesh Kumar]

Hi