The command set multiplot places gnuplot in the multiplot mode, in which several plots are placed next to each other on the same page or screen window. This produces a layout in which the boundary of both left subplots is 5 character widths from the left edge of the canvas, the right boundary of the right subplots is 1 character width from the canvas edge. See also multiplot demo multiplt. As you can see this is not an ideal case to use the space in the figure. Each plot can be scaled by scale and shifted with offset ; if the y-values for scale or offset are omitted, the x-value will be used.
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