1)   ZigZag 1.1 ZigZag is a handy tool to plot and explore math functions. It can plot Cartesian (Y(x) and X(y)), polar, parametric and also table-defined graphs 2)   ZGrapher 1.4 This graphing calculator can plot y(x), x(y), polar, parametric and table-defined functions. Calculus features include obtaining derivatives, equations of tangents and normals, numerical integration, regression analysis.