Warning: Square root of a negative number.
When taking the square root of an array, Sqrt(A), the warning may display if any value in the array is negative.
There are two methods for avoiding this warning without turning Show Result Warnings globally. These are demonstrated here.
If A >= 0 Then Sqrt(A) Else Null
The first instance is convenient and readable when you have a particular substitution value in mind. The second method evaluates faster.