2.24 yerrorbars

The yerrorbars (or errorbars) style is only relevant to 2D data plots. yerrorbars is like ‘points‘, except that a vertical error bar is also drawn. At each point (x,y), a line is drawn from (x,y-ydelta) to (x,y+ydelta) or from (x,ylow) to (x,yhigh), depending on how many data columns are provided. A tic mark is placed at the ends of the error bar (unless bars is used—see bars for details). Either 3 or 4 input columns are required.

     3 columns:  x  y  ydelta
     4 columns:  x  y  ylow  yhigh

See also errorbar demo.