A ComboBox holds a list of all function combinations described on the Fourier Coefficients page. When one is selected it is displayed in red. The antiderivative is calculated for the fundamental period and drawn as a blue curve. Its end value is the definite integral over one fundamental period, which is needed for the calculation of the coefficients. The integration process is slowed down to visualize more clearly the consequence of changes in parameters or indices.
Some of the selectable functions contain parameters a and b which can be changed continuously by sliders a/ b . Two other sliders m/n select the critical indices m and n as integers between 1 and 10.
Parameters and indices are maintained when functions are changed. Integration is started automatically at any change as long as the selection Integral remains active.
By means of sliders a and b scaling of the ordinate can be adjusted to the specific function. They also allow phase shifting of functions.