A Pólya plot is a plot of the vector field of of a complex function . Several examples are shown above.
Pólya plots can be created in the Wolfram Language using the following code:
PolyaFieldPlot[f_, {x_, xmin_, xmax_}, {y_, ymin_, ymax_}, opts : OptionsPattern[]] := VectorPlot[Evaluate @ {Re[f], -Im[f]}, {x, xmin, xmax}, {y, ymin, ymax}, VectorScale -> {Automatic, Automatic, Log[#5 + 1]&}, opts ]