oints x.

If `c` is of length `n + 1`, this function returns the value:

.. math:: p(x) = c_0 * T_0(x) + c_1 * T_1(x) + ... + c_n * T_n(x)

The parameter `x` is converted to an array only if it is a tuple or a
list, otherwise it is treated as a scalar. In either case, either `x`
or its elements must support multiplication and addition both with
themselves and with the elements of `c`.

If `c` is a 1-D array, then ``p(x)`` will have the same shape as `x`.  If
`c` is multidimensional, then the shape of the result depends on the
value of `tensor`. If `tensor` is true the shape will be c.shape[1:] +
x.shape. If `tensor` is false the shape will be c.shape[1:]. Note that
scalars have shape (,).

Trailing zeros in the coefficients will be used in the evaluation, so
they should be avoided if efficiency is a concern.

Parameters
----------
x : array_like, compatible object
    If `x` is a list or tuple, it is converted to an ndarray, otherwise
    it is left unchanged and treated as a scalar. In either case, `x`
    or its elements must support addition and multiplication with
    themselves and with the elements of `c`.
c : array_like
    Array of coefficients ordered so that the coefficients for terms of
    degree n are contained in c[n]. If `c` is multidimensional the
    remaining indices enumerate multiple polynomials. In the two
    dimensional case the coefficients may be thought of as stored in
    the columns of `c`.
tensor : boolean, optional
    If True, the shape of the coefficient array is extended with ones
    on the right, one for each dimension of `x`. Scalars have dimension 0
    for this action. The result is that every column of coefficients in
    `c` is evaluated for every element of `x`. If False, `x` is broadcast
    over the columns of `c` for the evaluation.  This keyword is useful
    when `c` is multidimensional. The default value is True.

Returns
-------
values : ndarray, algebra_like
    The shape of the return value is described above.

See Also
--------
chebval2d, chebgrid2d, chebval3d, chebgrid3d

Notes
-----
The evaluation uses Clenshaw recursion, aka synthetic division.

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