Trying to create an animation of the Nephroid of Freeth with Mathematica
Clear[z]; a = 1; Do[z[j] = PolarPlot[a*(1 + 2*Sin[t/2]), {t, 0, j}, Ticks -> False, PlotRange -> {{-3, 1.5}, {-2.5, 2.5}}], {j, 4 Pi/50, 4 Pi, 4 Pi/50}];
Try Manipulate:
a = 1; Manipulate[ PolarPlot[a (1 + 2 Sin[t/2]), {t, 0, j}, Ticks -> False, PlotRange -> {{-3, 1.5}, {-2.5, 2.5}}], {j, 4 Pi/50, 4 Pi, 4 Pi/50}]
Sure, you can export animation as a gif file: