xclear - clear a graphics window
Without any argument, this function clears the current window. Otherwise it clears the graphics windows whose numbers are included in the vector window-id. For example xclear(1:3) clears windows 1, 2 and 3. If one of the windows does not exist, then it is automatically created.
Warning: in recording mode xclear clears the window, but it does not erase the recorded commands. In this case you must use the function xbasc.