This dialog pops-up when you use the Vertical Cursor... command. By default, it displays a table that gives quick access to the values of the data points for all curves in a plot layer. The names of the curves available in the active plot layer are listed in the first column of this table. The second column displays the Y value corresponding to the X position of the cursor. The third column, called Show, enables/disables the display of the Y labels attached to each data curve in the plot layer. The << button can be used in order to hide this data table.
The X input box allows to manually and precisely set the position of the cursor. If a plot curve does not contain a data point with the specified abscissa, QtiPlot uses liniar interpolation in order to calculate the corresponding Y value.
The Layer input box can be used in order to change the active plot layer while the Font input box allows the user to increase or decrease the font size of the Y labels.
By default, the color of the vertical cursor is red and the line width is set to 1. These values can be customized using the Pen spin box and the color button located just after it.
When pressing the Table button, QtiPlot creates a new table with the Y values of all data curves in the active plot layer at the selected X coordinate. If the results table already exists, a new row of data is appended to it.
The Help button opens the quick help panel when pressed.
If the Snap Cursor to Nearest Data Point box is unchecked, the vertical cursor can be moved freely when holding the left button of the mouse pressed or when pressing the Left and Right arrow keys. Otherwise, when you move the cursor, its position will be automatically set to the nearest data point.