Calculator of Formulas

This app is focused on calculating and graphing mathematical formulas for everyday life and work. What distinguishes it from many other RPN calculators available at the App Store? Some of them allow for formula coding, do graphs, and are free, too. Unfortunately, most of these apps feature formulas of only one variable. In most real life applications, however, mathematical formulas have multiple variables! This app does all of the above plus the following:

* Programs mathematical formulas with up to six variables.
* Is simple to use.
* Plots graphs with respect to a chosen single variable while keeping all other variables fixed.
* Plots graphs when all the variables are changing along a user-prescribed vector. This relatively new concept of "ray plotting" enables user to probe a function in n dimensions by looking at its 1-dimensional slices.
* Does graph tracing and enables graph manipulation with a simple set of intuitive touch gestures instead of button/pop up controls.
* Saves most used formulas along with detailed description for later use.
* Creates tables of calculated results that can be pasted into other applications.
* Has an exhaustive set of help files and tutorials.