I had this dataset of my blood pressure and heart rate from yesterday: Replot # re-plot your data after making changes When you work from the Gnuplot command line, you’re working in a session: You can run shell commands from the Gnuplot command line: Set autoscale # let gnuplot determine ranges (default) It can be nice to have a grid on a chart, and it can also be nice to control the graph tickmarks, ranges, and origin: Plot sin(x) title 'Sin', tan(x) title 'Tangent' It’s fun and easy to plot formulas with Gnuplot: You can create ASCII plots in your Mac Terminal window: That series of commands creates this chart: Unset multiplot # exit multiplot mode (prompt changes back to 'gnuplot') Set multiplot # multiplot mode (prompt changes to 'multiplot')
How to show multiple graphs in the output: Plot sin(x) title 'Sine Function', tan(x) title 'Tangent' Plot '4col.csv' u 1:2 w l title 'Square', '4col.csv' u 1:3 w l title 'Double' Plot '4col.csv' using 1:2 with lines title 'Square', '4col.csv' using 1:3 with lines title 'Double' The second command shown creates this chart: Plot '4col.csv' using 1:2 with lines, '4col.csv' using 1:3 with lines, '4col.csv' using 1:4 with lines Plot '4col.csv' using 1:2 with lines, '4col.csv' using 1:3 with lines To show multiple curves on one plot, use the 4col.csv file: You can adorn your plots with titles, labels, legend, arrows, and more: Plot '2col.csv' u 1:2 w l title 'Squared' # 'u' - using, 'w l' - with lines
Plot '2col.dat' using 2:1 # 2=x, 1=y (reverse the graph) Plot '2col.dat' using 1:2 # 1=x, 2=y (this is the default) Plot '2col.dat' with lines title 'my curve' # this is really the line-title in the legend Plot '2col.dat' with linespoints # plot only elements 3 thru 7 Plot '2col.dat' with linespoints # plot the first 5 elements Plot '2col.dat' with points # just points (default) Plot '2col.dat' with linespoints # line and points Plot '2col.dat' with lines # connect points with a line Plot '2col.dat' # assumes col1=x, col2=y shows '+' at data points
To get started, you can use MacPorts or Homebrew to install Gnuplot on Mac OS X systems:
If you haven’t used it before, it’s an amazing tool for creating graphs and charts. I needed to use Gnuplot a little bit over the last few days, mostly to create 2D line charts, and these are my brief notes on how to get started with Gnuplot.