The Num command in 4D v11 SQL accepts a parameter for the decimal separator.

Num (expression; separator) > Number

The decimal separator is interpreted as a decimal place and must be embedded in a numeric string.

In addition using the GET SYSTEM FORMAT you can determine what Decimal separator is being used by the system. For example:

If you have a string:

$numerical_string:="1,458.95"

You use the Num command without the decimal separator parameter, in a system that does not use a period as a decimal separator you will not get the right numeric value.

$numerical_value:=Num($numerical_string)

This will result in 1.45895 in a system using "," as the decimal separator. The same expression with the decimal separator parameter will result in the right numerical value.

$numerical_value:=Num($numerical_string;".")

This will result in 1,458.95 for a system using "." as a decimal separator or 1.458,95 for a system using "," as the decimal separator.

For more information see the Num command documentation:
http://www.4d.com/docs/CMU/CMU00011.HTM