Hello. I apologize for my English.
In Shenghui Yang’s response to Mathieu Auffray’s post titled " Pure imaginary complex number " there are two colored figures.
What does the number “12” in the first figure and the number “7.2” in the second figure mean?
Can these two numbers be determined manually?
Many thanks.
The plot legend shows Abs[f[z]] in grayscale and Arg[f[z]] in hue colors. This depends on the ColorFunction. The tick value (12 or 7.2) indicates where White starts. The cutoff is probably chosen by ComplexPlot so that (1) no more than a small fraction of the plot is white and (2) the rest of the plot has a large “dynamic range” of color intensities.
You can get both an upper and a lower tick, showing the cutoffs for white and dark gray, respectively. Example from the documentation for ComplexPlot, option ColorFunction, with PlotLegends added:
ComplexPlot[(z^2 + 1)/(z^2 - 1), {z, -2 - 2 I, 2 + 2 I},
ColorFunction -> "QuantileAbs", PlotLegends -> Automatic]
Many thanks.