is_constant

typhoon.test.signals.is_constant(signal, at_value, during=None, strictness=1, report_plot=None)

Checks if signal is always inside defined range.

Parameters:

  • signal (pandas.Series) – Signal to be tested for.

  • at_value (tuple/list or number) – Band inside with signal should always be. Can be passed as a tuple/list with two elements for a range, or as a single value for an exact value.

  • during (tuple) – Time period (as a range) to be considered for analysis.

  • strictness (float) – Number between 0.0 and 1.0 that determines percentage of time signal should be inside the defined range for test to pass.

  • report_plot (dict) –

    Dictionary which overrides default allure report plot attachment behaviour. It also overrides behaviour specified for whole test run with command line arguments --analysis-plot-type and --analysis-plot-on-fail-only. Dictionary has two keys to be specified:

    1. type: specifies which kind of allure plot should be used. Valid values:

      • static - only matplotlib plot attached as .png picture is attached

      • interactive - only interactive html plot created with bokeh library is attached. Advantage of this plot it has options to zoom in/zoom out. Disadvantage is that it consumes significantly more memory.

      • none - none of the plots will be attached

      • all - all plots will be added. Currently supported ones are matplotlib plot(static) and bokeh plot(interactive)

    2. when: specifies when to add plots that are specified with previous key to report. Available options:

      • always - always adds specified plots

      • on-fail - adds plots only if comparison of reference and measured signal fails. This is good way to decrease size of allure plots.

    Note

    If report_plot argument is not provided, and command line arguments --analysis-plot-type and analysis-plot-on-fail-only are not specified, default behaviour is static plot, attached always. If command line arguments are specified, they define new default behaviour for whole test run.

Returns:

result – Result of the analysis.

Return type:

AnalysisResult

Examples

>>> val = 220
>>> tol = val * 0.01
>>> result = is_constant(capture["Va_rms"], at_value=(val-tol, val+tol))
>>> assert result == True, result.msg

or

>>> from typhoon.test.ranges import around
>>> result = is_constant(capture["Va_rms"], at_value=around(val, tol_p=0.01))
>>> assert result == True, result.msg

A more compact and readable function is obteined using assertion helpers:

>>> assert_is_constant(capture["Va_rms"], at_value=around(val, tol_p=0.01))

See also

typhoon.test.signals.AnalysisResult, typhoon.test.signals.assert_is_constant