Returns the floating point number represented by the value that is associated with @key, or @default_val if the value does not represent a floating point number.
Floating point numbers are parsed with g_ascii_strtod().
a key
the default value
Return: the floating point number associated with @key
2.10
See Implementation
Returns the floating point number represented by the value that is associated with @key, or @default_val if the value does not represent a floating point number.
Floating point numbers are parsed with g_ascii_strtod().