GraphFunc - A program online that is used to plot the graph of mathematical functions in two or three dimensions. [Java required] Calculus Applets at St. Louis University - Provides applets demonstrating concepts of both single and multivariable calculus. Calculus Problem Solver - A calculus tutorial software that can solve differentiation problems and generate step-by-step solutions. Tests differentiation skills by generating dynamic quizzes. PEEI - A computer program for the numerical solution of systems of partial differential equations. Provided by Giacomo Lorenzoni. Wolfram Mathematica Online Integrator - Allows users to enter an integrand in order to return the indefinite integral. SymPy - A Python library for symbolic mathematics.