+#!/usr/bin/gnuplot -persist
+#
+#
+# G N U P L O T
+# Version 4.6 patchlevel 6 last modified September 2014
+# Build System: Linux x86_64
+#
+# Copyright (C) 1986-1993, 1998, 2004, 2007-2014
+# Thomas Williams, Colin Kelley and many others
+#
+# gnuplot home: http://www.gnuplot.info
+# faq, bugs, etc: type "help FAQ"
+# immediate help: type "help" (plot window: hit 'h')
+
+set title "Seasonal phenomenon, highlighted using a polar graph"
+
+set xdata time
+set timefmt "%Y-%m-%d"
+set format x "%s"
+
+# Dummy plot to gather some stats from the dataset
+set terminal unknown
+plot 'data.dat' using 1:2
+
+xmin = GPVAL_DATA_X_MIN
+xmax = GPVAL_DATA_X_MAX
+ymin = GPVAL_DATA_Y_MIN
+ymax = GPVAL_DATA_Y_MAX
+
+set polar
+set border 0
+set grid polar back lw 1
+set nokey
+
+unset xtics
+unset ytics
+unset raxis
+
+set size square
+
+# XXX: offsets may need to be adjusted for a different data set
+set offsets 0, 0.2, 0.1, 0.1
+
+set rrange [ymin:ymax + 0.5]
+
+# XXX: rtics may need to be adjusted for a different data set
+#set rtics ymin,1
+
+year_min = tm_year(xmin)
+year_max = tm_year(xmax)
+
+set cbrange [year_min:year_max + 1]
+
+# Generate colorbox labels programmatically
+cblabels = 'set cbtics ( '
+do for [i=year_min:year_max] {
+ cblabels = cblabels . '"' . i .'" ' . i .','
+}
+cblabels = cblabels . '"" ' . (i + 1) .','
+cblabels = cblabels . ' )'
+eval(cblabels)
+
+# The value 12 works well with the default colorbox height
+cbtics_offset = 12 / (year_max - year_min)
+set cbtics offset 0,+cbtics_offset
+
+set palette rgbformulae 31,-11,32
+set palette maxcolors (year_max - year_min + 1)
+
+# The radius below places the labels outside of the grid.
+#
+# XXX: It depends on the magnitude of the data values tho, and it may need to
+# be adjusted for a different data set.
+r = 1.6
+set_label(x, text) = sprintf("set label '%s' at (%f*cos(%f)), (%f*sin(%f)) center", text, r, x, r, x)
+
+# Create labels for the months, apparently gnuplot does not allow to set ttics
+month_angle(x) = x * 2 * pi / 12 + pi / 12
+eval set_label(month_angle(0), "Jan")
+eval set_label(month_angle(1), "Feb")
+eval set_label(month_angle(2), "Mar")
+eval set_label(month_angle(3), "Apr")
+eval set_label(month_angle(4), "May")
+eval set_label(month_angle(5), "Jun")
+eval set_label(month_angle(6), "Jul")
+eval set_label(month_angle(7), "Aug")
+eval set_label(month_angle(8), "Sep")
+eval set_label(month_angle(9), "Oct")
+eval set_label(month_angle(10), "Nov")
+eval set_label(month_angle(11), "Dec")
+
+# Scale the data so that one year covers one circumference,
+# this allows samples in the same time of the year to be at the same angles.
+one_year = 60 * 60 * 24 * 365.25
+scale_date_to_month_polar(x) = (int(x) % int(one_year)) / one_year * (2 * pi)
+
+# With this hacky-ish wrap() function we loose some points when the data wraps
+# around, but AFAIK this is unavoidable without preprocessing the data.
+year_wrap(old, new) = tm_year(old) == tm_year(new) ? scale_date_to_month_polar(new) : NaN
+
+if (GPVAL_VERSION < 5.0) \
+ tcol(x) = timecolumn(x); \
+else \
+ tcol(x) = timecolumn(x, "%Y-%m-%d")
+
+set terminal qt 0
+#set terminal png notransparent nocrop truecolor rounded enhanced font "arial,8" fontscale 1.0
+#set output 'modular_polar.png'
+
+saved = -1
+plot \
+ 'data.dat' using (prev=saved, saved=tcol(1), year_wrap(prev, saved)):2:(tm_year(tcol(1))) with lines lc palette lw 1.5
projects / experiments / gnuplot_seasonal_plot.git / commitdiff