PHP Manual: variant

Description

mixed variant_div ( mixed left, mixed right )

Divides left by right and returns the result, subject to the following rules:

Table 1. Variant Division Rules

If	Then
Both expressions are of the string, date, character, boolean type	Double is returned
One expression is a string type and the other a character	Division and a double is returned
One expression is numeric and the other is a string	Division and a double is returned.
Both expressions are numeric	Division and a double is returned
Either expression is NULL	NULL is returned
`right` is empty and `left` is anything but empty	A com_exception with code `DISP_E_DIVBYZERO` is thrown
`left` is empty and `right` is anything but empty.	0 as type double is returned
Both expressions are empty	A com_exception with code `DISP_E_OVERFLOW` is thrown

Note: As with all the variant arithmetic functions, the parameters for this function can be either a PHP native type (integer, string, floating point, boolean or NULL), or an instance of a COM, VARIANT or DOTNET class. PHP native types will be converted to variants using the same rules as found in the constructor for the VARIANT class. COM and DOTNET objects will have the value of their default property taken and used as the variant value.
The variant arithmetic functions are wrappers around the similarly named functions in the COM library; for more information on these functions, consult the MSDN library. The PHP functions are named slightly differently; for example variant_add() in PHP corresponds to VarAdd() in the MSDN documentation.