These are the projects that are part of the Coding Together iTunes course available on [iTunes U](http://itunes.apple.com/us/course/coding-together-apps-for-iphone/id537447071).
Add a Graph button to your calculator’s user-interface that, when pressed, segues to a new MVC (that you will have to write) by pushing it onto the UINavigationController’s stack (on the iPhone). The new MVC graphs whatever program was in the calculator when the button was pressed. To draw the graph you will iterate over all the pixels in your view horizontally (x) and use +runProgram:usingVariableValues: to get the corresponding vertical (y) value. You will, of course, have to convert to/from your view’s coordinate system from/to a reasonable graph coordinate system. You will need a scale and origin to do this coordinate system conversion. If the user has not already chosen a scale and origin for the graph (see ticket #27 and #28), pick a reasonable starting scale and origin.
Add a Graph button to your calculator’s user-interface that, when pressed, segues to a new MVC (that you will have to write) by pushing it onto the UINavigationController’s stack (on the iPhone). The new MVC graphs whatever program was in the calculator when the button was pressed. To draw the graph you will iterate over all the pixels in your view horizontally (x) and use +runProgram:usingVariableValues: to get the corresponding vertical (y) value. You will, of course, have to convert to/from your view’s coordinate system from/to a reasonable graph coordinate system. You will need a scale and origin to do this coordinate system conversion. If the user has not already chosen a scale and origin for the graph (see ticket #27 and #28), pick a reasonable starting scale and origin.