def calc_phi_total(x, data):
    ' Returns the sum of the normalized relative error of the updated Voce-Chaboche material model given x.\n\n    :param np.array x: Updated Voce-Chaboche material model parameters.\n    :param list data: (pd.DataFrame) Stress-strain history for each test considered.\n    :return float: Normalized error value expressed as a percent (raw value * 100).\n\n    The normalized error is defined in de Sousa and Lignos (2017).\n    '
    error_total = 0.0
    area_total = 0.0
    for d in data:
        (error, area) = normalized_error_single_test_uvc(x, d)
        error_total += error
        area_total += area
    return (np.sqrt((error_total / area_total)) * 100.0)
Returns the sum of the normalized relative error of the updated Voce-Chaboche material model given x.

:param np.array x: Updated Voce-Chaboche material model parameters.
:param list data: (pd.DataFrame) Stress-strain history for each test considered.
:return float: Normalized error value expressed as a percent (raw value * 100).

The normalized error is defined in de Sousa and Lignos (2017).
def calc_phi_total(x, data):
    ' Returns the sum of the normalized relative error of the updated Voce-Chaboche material model given x.\n\n    :param np.array x: Updated Voce-Chaboche material model parameters.\n    :param list data: (pd.DataFrame) Stress-strain history for each test considered.\n    :return float: Normalized error value expressed as a percent (raw value * 100).\n\n    The normalized error is defined in de Sousa and Lignos (2017).\n    '
    error_total = 0.0
    area_total = 0.0
    for d in data:
        (error, area) = normalized_error_single_test_uvc(x, d)
        error_total += error
        area_total += area
    return (np.sqrt((error_total / area_total)) * 100.0)