econml/utilities.py
def concatenate(XS, axis=0):
    """
    Join a sequence of arrays along an existing axis.

    Parameters
    ----------
    X1, X2, ... : sequence of array_like
        The arrays must have the same shape, except in the dimension
        corresponding to `axis` (the first, by default).

    axis : int, optional
        The axis along which the arrays will be joined.  Default is 0.

    Returns
    -------
    ndarray or SparseArray
        The concatenated array. It will be sparse if the inputs are.
    """
    def conc(*XS):
        return sp.concatenate(XS, axis=axis) if iscoo(XS[0]) else np.concatenate(XS, axis=axis)
    return _apply(conc, *XS)

    Join a sequence of arrays along an existing axis.

    Parameters
    ----------
    X1, X2, ... : sequence of array_like
        The arrays must have the same shape, except in the dimension
        corresponding to `axis` (the first, by default).

    axis : int, optional
        The axis along which the arrays will be joined.  Default is 0.

    Returns
    -------
    ndarray or SparseArray
        The concatenated array. It will be sparse if the inputs are.
    
Join a sequence of arrays along an existing axis.
Parameters



axis : int, optional
The axis along which the arrays will be joined.  Default is 0.

Returns

ndarray or SparseArray
The concatenated array. It will be sparse if the inputs are.
Join a sequence of arrays along an existing axis . Parameters axis : int optional The axis along which the arrays will be joined . Default is 0 . Returns ndarray or SparseArray The concatenated array . It will be sparse if the inputs are .
def concatenate(XS, axis=0):
    def conc(*XS):
        return sp.concatenate(XS, axis=axis) if iscoo(XS[0]) else np.concatenate(XS, axis=axis)
    return _apply(conc, *XS)
def concatenate ( XS , axis = 0 ) : def conc ( * XS ) : return sp . concatenate ( XS , axis = axis ) if iscoo ( XS [ 0 ] ) else np . concatenate ( XS , axis = axis ) return _apply ( conc , * XS )
Join a sequence of arrays along an existing axis.
Join a sequence of arrays along an existing axis .
"""
    Join a sequence of arrays along an existing axis.

    Parameters
    ----------
    X1, X2, ... : sequence of array_like
        The arrays must have the same shape, except in the dimension
        corresponding to `axis` (the first, by default).

    axis : int, optional
        The axis along which the arrays will be joined.  Default is 0.

    Returns
    -------
    ndarray or SparseArray
        The concatenated array. It will be sparse if the inputs are.
    """
XS
axis