Sign

Syntax:

SIGN(number)

• number: A numeric value whose sign you want to determine. This can be positive, negative, or zero.

Description:

The SIGN function in Excel returns the sign of a number. It indicates whether the number is positive, negative, or zero, and returns:

• 1 if the number is positive
• -1 if the number is negative
• 0 if the number is zero

Examples:

1. SIGN(10) would return 1 because 10 is positive.
2. SIGN(-5.5) would return -1 because -5.5 is negative.
3. SIGN(0) would return 0 because the number is zero.
4. SIGN(-0.001) would return -1 because even small negative values are treated as negative.

Notes:

• The Rust implementation provided uses the f64 data type for the input and returns an i32 value to match the results of the SIGN function in Excel.
• This implementation can handle both integer and floating-point numbers as long as they are converted to f64.
• If the input is NaN or infinity (f64::NAN or f64::INFINITY), you might want to handle these cases separately based on your application's requirements.