Returns the values associated with key under group_name as
doubles.
If key cannot be found then null is returned and error is set to
G_KEY_FILE_ERROR_KEY_NOT_FOUND. Likewise, if the values associated
with key cannot be interpreted as doubles then null is returned
and error is set to G_KEY_FILE_ERROR_INVALID_VALUE.
the values associated with the key as a list of doubles, or null if the
key was not found or could not be parsed. The returned list of doubles
should be freed with glib.global.gfree when no longer needed.
Returns the values associated with key under group_name as doubles.
If key cannot be found then null is returned and error is set to G_KEY_FILE_ERROR_KEY_NOT_FOUND. Likewise, if the values associated with key cannot be interpreted as doubles then null is returned and error is set to G_KEY_FILE_ERROR_INVALID_VALUE.