This dialog box is opened when you select the Integrate... command from the Analysis menu. The dialog displays a different set of controls depending if you are integrating data from a table or from a plot curve.
Pressing the Integrate button performs a numerical integration using the trapezoidal method. The result of the integration is listed in the Log Panel.
If the Sort data option is checked the data is sorted before performing the integration with respect to the X values associated to the input columns or to the abscissas of the curve to be integrated. This option is not available if the input data columns come from a table window without any designated X column. In this case the input data is assigned by default with ascending X values.
By checking the Show plot option a new graph window will be created containing a plot of the integrated curve, the data for which is stored in a new (hidden) table. QtiPlot stores the integration operation into this output graph window if the Recalculate option is other than No. By setting this option to Auto any modification of the input data will trigger a recalculation of the value of the integral.