The aspect ratio is defined by the ratio of the number of pixels for one data unit on the y axis and the number of pixels for one data unit on the x axes.
Usage
l_aspect(widget) <- valueDetails
Changing the aspect ratio with l_aspect<- changes effectively
the zoomY state to obtain the desired aspect ratio. Note that the
aspect ratio in loon depends on the plot width, plot height and the states
zoomX, zoomY, deltaX, deltaY and
swapAxes. Hence, the aspect aspect ratio can not be set permanently
for a loon plot.
