gnuplot documentation
gnuplot documentation
gnuplot documentation
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76 <strong>gnuplot</strong> 4.3 60 PLOT<br />
Tic labels may be read for any of the plot axes: x x2 y y2 z. The ticlabels() specifiers must<br />
come after all of the data coordinate specifiers in the using portion of the command. For each data<br />
point which has a valid set of X,Y[,Z] coordinates, the text field found in column is added<br />
to the list of xtic labels at the same X coordinate as the point it belongs to. xticlabels()<br />
may be shortened to xtic().<br />
Example:<br />
splot "data" using 2:4:6:xtic(1):ytic(3):ztic(6)<br />
In this example the x and y axis tic labels are taken from different columns than the x and y coordinate<br />
values. The z axis tics, however, are generated from the z coordinate of the corresponding point.<br />
60.2.9.3 X2ticlabels See plot using xticlabels (p. 75).<br />
60.2.9.4 Yticlabels See plot using xticlabels (p. 75).<br />
60.2.9.5 Y2ticlabels See plot using xticlabels (p. 75).<br />
60.2.9.6 Zticlabels See plot using xticlabels (p. 75).<br />
60.3 Errorbars<br />
Error bars are supported for 2D data file plots by reading one to four additional columns (or using<br />
entries); these additional values are used in different ways by the various errorbar styles.<br />
In the default situation, <strong>gnuplot</strong> expects to see three, four, or six numbers on each line of the data file<br />
— either<br />
(x, y, ydelta),<br />
(x, y, ylow, yhigh),<br />
(x, y, xdelta),<br />
(x, y, xlow, xhigh),<br />
(x, y, xdelta, ydelta), or<br />
(x, y, xlow, xhigh, ylow, yhigh).<br />
The x coordinate must be specified. The order of the numbers must be exactly as given above, though<br />
the using qualifier can manipulate the order and provide values for missing columns. For example,<br />
plot ’file’ with errorbars<br />
plot ’file’ using 1:2:(sqrt($1)) with xerrorbars<br />
plot ’file’ using 1:2:($1-$3):($1+$3):4:5 with xyerrorbars<br />
The last example is for a file containing an unsupported combination of relative x and absolute y errors.<br />
The using entry generates absolute x min and max from the relative error.<br />
The y error bar is a vertical line plotted from (x, ylow) to (x, yhigh). If ydelta is specified instead of<br />
ylow and yhigh, ylow = y - ydelta and yhigh = y + ydelta are derived. If there are only two numbers<br />
on the record, yhigh and ylow are both set to y. The x error bar is a horizontal line computed in the<br />
same fashion. To get lines plotted between the data points, plot the data file twice, once with errorbars<br />
and once with lines (but remember to use the notitle option on one to avoid two entries in the key).<br />
Alternately, use the errorlines command (see errorlines (p. 77)).<br />
The error bars have crossbars at each end unless set bars is used (see set bars (p. 88) for details).<br />
If autoscaling is on, the ranges will be adjusted to include the error bars.<br />
See also<br />
errorbar demos.<br />
See plot using (p. 74), plot with (p. 79), and set style (p. 130) for more information.