def as_column(a):
 if (a.ndim != 1):
  raise ValueError(('as_column expected an 1-dimensional array, but got an array of shape %s' % a.shape))
 return a[:, None]

def as_column ( a ) : if ( a . ndim != 1 ) : raise ValueError ( ( 'as_column expected an 1-dimensional array, but got an array of shape %s' % a . shape ) ) return a [ : , None ]
convert an array of shape into an array of shape .