This equation converts the numeric grade point corresponding to a letter grade input.
original author: habbes
Besides simply providing the value to the user, this equation is an important equation-in-equation (EiE) for use inside other vCalc equations. For example, in the vCalc editor you can drag-and-drop this equation into an equation computing a student's GPA. If the letter grades for a whole class were stored in a vCalc data set, you could pull each successive class grade from a selected student and using this equation as an EiE, convert each class letter grade into a numeric value to be averaged in the GPA calculation for that student.