# xarray.Variable.concat

classmethod `Variable.``concat`(variables, dim='concat_dim', positions=None, shortcut=False)

  Concatenate variables along a new or existing dimension.

  Parameters:

  - variables (iterable of Array) – Arrays to stack together. Each variable is expected to have matching dimensions and shape except for along the stacked dimension.
  - dim (str or DataArray, optional) – Name of the dimension to stack along. This can either be a new dimension name, in which case it is added along axis=0, or an existing dimension name, in which case the location of the dimension is unchanged. Where to insert the new dimension is determined by the first variable.
  - positions (None or list of integer arrays, optional) – List of integer arrays which specifies the integer positions to which to assign each dataset along the concatenated dimension. If not supplied, objects are concatenated in the provided order.
  - shortcut (bool, optional) – This option is used internally to speed-up groupby operations. If shortcut is True, some checks of internal consistency between arrays to concatenate are skipped.

  Returns: | stacked – Concatenated Variable formed by stacking all the supplied variables along the given dimension.
  Return type: | Variable