set datafile columnheaders

The set datafile columnheaders command guarantees that the first row of input will be interpreted as column headers rather than as data values. It affects all input data sources to plot, splot, fit, and stats commands. If this setting is disabled by unset datafile columnheaders, the same effect is triggered on a per-file basis if there is an explicit columnheader() function in a using specifier or plot title associated with that file. See also set key autotitle and columnheader.