getDouble
Returns the value associated with @key under @group_name as a double. If @group_name is null, the start_group is used.
If @key cannot be found then 0.0 is returned and @error is set to %G_KEY_FILE_ERROR_KEY_NOT_FOUND. Likewise, if the value associated with @key cannot be interpreted as a double then 0.0 is returned and @error is set to %G_KEY_FILE_ERROR_INVALID_VALUE.
Return
the value associated with the key as a double, or 0.0 if the key was not found or could not be parsed.
Since
2.12
Parameters
groupName
a group name
key
a key