'Set scalar value into the array.
Parameters
indexer : any
The indexer to set the value at.
value : str
The value to assign at the given locations.
Raises
ValueError
Raised when ``value`` is not a value element of this this label
array.'

def set_scalar(self, indexer, value):

    try:
        value_code = self.reverse_categories[value]
    except KeyError:
        raise ValueError(('%r    is    not    in    LabelArray    categories.' % value))
    self.as_int_array()[indexer] = value_code
