IsNonPositive
Tests if a numeric entity is nonpositive.
Syntax

IsNonPositive(x[, ε])

x
is a number, a vector, or a matrix 
ε
is a positive number

Description
If x
is a number, a vector, or a matrix, then IsNonPositive(x, ε)
returns true
iff x
is nonpositive, all components of x
are nonpositive, or all entries of x
are nonpositive, respectively. Floatingpoint numbers are compared using epsilon ε
. If omitted, a default (nonzero) value will be used for ε
.
Examples
IsNonPositive(−IdentityMatrix(5))
true