Check the `input_sample` is valid

        Checks input sample is:
            - the correct size
            - values between 0 and 1

        Arguments
        ---------
        input_sample : numpy.ndarray
        num_params : int
        num_samples : int

def check_input_sample(input_sample, num_params, num_samples):
        """Check the `input_sample` is valid

        Checks input sample is:
            - the correct size
            - values between 0 and 1

        Arguments
        ---------
        input_sample : numpy.ndarray
        num_params : int
        num_samples : int
        """
        assert type(input_sample) == np.ndarray, \
            "Input sample is not an numpy array"
        assert input_sample.shape[0] == (num_params + 1) * num_samples, \
            "Input sample does not match number of parameters or groups"
        assert np.any((input_sample >= 0) | (input_sample <= 1)), \
            "Input sample must be scaled between 0 and 1"