Plotter

Use a picture. It's worth a thousand words.

-- "Speakers Give Sound Advice". Syracuse Post Standard. page 18. March 28, 1911.

Graphs are a great way to summarize lots of data for rapid consumption by humans. Unfortunately, graphs aren't quite data, in that they're most useful when they are lossy representations.

Plotter is a simple toolkit which attempts to keep graphs in a composable data-first representation for as long as possible, enabling them to be listed for simultaneous display in a graph and ultimately rendered to a graphic.

Demo

user> (require '[plotter.core :refer :all])
nil
user> (def sin (->curve #(Math/sin %) :title "sin(x)"))
#'user/sin
user> (def cos (->curve #(Math/cos %) :title "cos(x)"))
#'user/cos
user> (render! (compose sin cos)
         :min 0
         :max (* 4 Math/PI)
         :step 0.1
         :y-min -2
         :y-max 2
         :size 500
         )
{:exit 0,
 :out "",
 :err "",
 :script "#!/usr/bin/env gnuplot
set autoscale
set terminal \"png\" size 3000, 3000
set output \"/tmp/graph_251417161639590865.png\"
plot [] [-2:2] \"/tmp/points_1074626684104989046.txt\" using 1:2 title \"sin(x)\", \"/tmp/points_717203087347687554.txt\" using 1:2 title \"cos(x)\"
quit",
 :graph #object[java.net.URI "0x1c754b93" "file:/tmp/graph_251417161639590865.png"]}
user>

API Overview

plotter.core/->curve

• (->curve f)
• (->curve f & {:as kwargs})

Function for constructing plottable curves from functions.

f is a function of one argument, the polar x, producing a numeric value for the single polar y at that point. This does require that f be a proper function which is single-valued.

Supported options:

• :coordinates, at present only ::p/polar is supported
• :title, an optional string which will be used as this curve's label

plotter.core/->points

• (->points coll)
• (->points coll & {:as kwargs})

Function for constructing plottable curves given data sets of points as a collection of polar [x y] pairs with no error component.

Supported options:

• :coordinates, at present only ::p/polar is supported
• :title, an optional string which will be used as this curve's label

plotter.core/compose

• (compose & graphs-or-curvables)

Function for "composing" together a zero or more "plottables" - being either graphs, curves or objects which can be coerced to a curve via #'plotter.core/as-curve.

Returns a graph containing all the plottables, which must all be in the same coordinate system.

plotter.core/as-curve

Function for coercing objects to plottable curves.

Supports functions which are assumed to be unary, representing a polar plot. Does not transform objects which are already curves.

plotter.core/render!

• (render! graph & {:as kwargs})

Given a graph and optional keyword arguments, render the curves constituting the graph to points and plot the points via gnuplot.

Supported options:

• :min the smallest (and first) x value to be plotted (default 0)
• :max the largest x value to be plotted (default 100)
• :step the interval on x at which to plot function points (default 0.1)
• :autoscale (true by default) tells gnuplot to size the graph
• :size either a single integer denoting a square image, or a pair denoting the rectangular dimensions of the image.
• :{x,y}-{min,max} specify limits on the dimensions of the graph
• :title sets the graph's title
• :image-format (png default )tells gnuplot what kind of image to produce.

License

Copyright (C) 2018 Reid "arrdem" McKenzie

Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.