query.py 文件源码

def snap_to_grid(self, *args, **kwargs):
        """
        Snap all points of the input geometry to the grid.  How the
        geometry is snapped to the grid depends on how many arguments
        were given:
          - 1 argument : A single size to snap both the X and Y grids to.
          - 2 arguments: X and Y sizes to snap the grid to.
          - 4 arguments: X, Y sizes and the X, Y origins.
        """
        if False in [isinstance(arg, (float,) + six.integer_types) for arg in args]:
            raise TypeError('Size argument(s) for the grid must be a float or integer values.')

        nargs = len(args)
        if nargs == 1:
            size = args[0]
            procedure_fmt = '%(geo_col)s,%(size)s'
            procedure_args = {'size': size}
        elif nargs == 2:
            xsize, ysize = args
            procedure_fmt = '%(geo_col)s,%(xsize)s,%(ysize)s'
            procedure_args = {'xsize': xsize, 'ysize': ysize}
        elif nargs == 4:
            xsize, ysize, xorigin, yorigin = args
            procedure_fmt = '%(geo_col)s,%(xorigin)s,%(yorigin)s,%(xsize)s,%(ysize)s'
            procedure_args = {'xsize': xsize, 'ysize': ysize,
                              'xorigin': xorigin, 'yorigin': yorigin}
        else:
            raise ValueError('Must provide 1, 2, or 4 arguments to `snap_to_grid`.')

        s = {'procedure_fmt': procedure_fmt,
             'procedure_args': procedure_args,
             'select_field': GeomField(),
             }

        return self._spatial_attribute('snap_to_grid', s, **kwargs)