Plotting and/or Graphing

>>> from pyproj import Proj
>>> p = Proj(proj='utm',zone=10,ellps='WGS84') # use kwargs
>>> x,y = p(-120.108, 34.36116666)
>>> 'x=%9.3f y=%11.3f' % (x,y)
'x=765975.641 y=3805993.134'
>>> 'lon=%8.3f lat=%5.3f' % p(x,y,inverse=True)
'lon=-120.108 lat=34.361'
>>> # do 3 cities at a time in a tuple (Fresno, LA, SF)
>>> lons = (-119.72,-118.40,-122.38)
>>> lats = (36.77, 33.93, 37.62 )
>>> x,y = p(lons, lats)
>>> 'x: %9.3f %9.3f %9.3f' % x
'x: 792763.863 925321.537 554714.301'
>>> 'y: %9.3f %9.3f %9.3f' % y
'y: 4074377.617 3763936.941 4163835.303'
>>> lons, lats = p(x, y, inverse=True) # inverse transform
>>> 'lons: %8.3f %8.3f %8.3f' % lons
'lons: -119.720 -118.400 -122.380'
>>> 'lats: %8.3f %8.3f %8.3f' % lats
'lats:   36.770   33.930   37.620'
>>> p2 = Proj('+proj=utm +zone=10 +ellps=WGS84') # use proj4 string
>>> x,y = p2(-120.108, 34.36116666)
>>> 'x=%9.3f y=%11.3f' % (x,y)
'x=765975.641 y=3805993.134'
>>> p = Proj(init="epsg:32667")
>>> 'x=%12.3f y=%12.3f (meters)' % p(-114.057222, 51.045)
'x=-1783486.760 y= 6193833.196 (meters)'
>>> p = Proj("+init=epsg:32667",preserve_units=True)
>>> 'x=%12.3f y=%12.3f (feet)' % p(-114.057222, 51.045)
'x=-5851322.810 y=20320934.409 (feet)'

# What display/output right now?
show terminal

# Make PNGs
set terminal png
size 800,600
[no]transparent

# PostScript
set term post portrait color "Times-Roman" 14

# SVG - warning: produces XML, need to pipe that off somewhere.
set term svg size 600,400

# ASCII Art
set terminal dumb

# Wxt - wxWidget interactive window, works pretty well
# The number (0 here) is plot window number. Juggle multiple windows
# with this.
set term wxt 0

# X11 - old school X
set term x11 enhanced font "arial,15"

# Key a.k.a. Legend - useful, almost essential, for plotting only one variable.
set key off

# Set plot aspect ratio
set size square # Same as "ratio 1".
set size ratio .5 # Height is half as long as width.

# Plotting
plot "file1","file2"

# Borders
set border
unset border
show border

# Labels
set label 0 "The Origin" at 0,0 center font "Arial,12"
unset label 0 # Can use any integer or not use them and auto increment.

# Linetype
set linetype 1 lc rgb "dark-red" lw 2 pt 5

# Log - pick axes x, y, xy Also can specify a base (like 2) 10 is default
set logscale xy

# Margin - distance between plot border and edge of canvas
# Units are height and width of characters. Whatever that means.
set bmargin 2

# Multiplot... Many plots on one canvas. Look up:
set multiplot { layout <rows>,<cols> }
# Do some plotting
unset multiplot # This should cause them to be rendered.

# Ticks
set xtics 0,5,10
set ytics add (3.141)
set mytics 10 # minor tics

plot
"mydatafile" using 1:3 with linespoints
   title "Thing One"
   pointtype 13
   linecolor "green"
   linewidth 1,
"mydatafile" using 1:($2) with linespoints
   title "Thing Two"
   axes x1y2
   pointtype 7
   linecolor rgb "#770077"
   linewidth 4

set polar
set angles degrees
set term dumb
set tics scale 0
set style line 2 pt 14
plot "-" with linespoints pointtype 15 notitle
 10 76.9156
 20 39.4343
 30 26.6504
 40 20.2422
 50 13.8997
 60 9.85593
 70 8.06027
 80 7.23516
 90 6.99576
e

  14 +--------+--------+-------+--------+--------+--------+-------+--------+
     |                    ***********O*****************                    |
  13 +             O*****O                             ****************O   +
     |            *                                                        |
     |           *                                                         |
  12 +          *                                                          +
     |         *                                                           |
  11 +        *                                                            +
     |       O                                                             |
  10 +       *                                                             +
     |      *                                                              |
     |      *                                                              |
   9 +     *                                                               +
     |   O                                                                 |
   8 +  *                                                                  +
     | O                                                                   |
     |O                                                                    |
   7 O                                                                     +
     |                                                                     |
   6 +--------+--------+-------+--------+--------+--------+-------+--------+
     0        10       20      30       40       50       60      70       80

import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
plt.plot([1,2,3])
plt.savefig('myfig')

#!/usr/bin/python
import math
import numpy as np
import matplotlib.pyplot as plt

# Define axes' range.
plt.axis([0, 6, -10, 20]) # 0 to 6 on X, -10 to +20 on Y

# Normal arrays work fine.
plt.plot([1,2,3,4], [1,4,9,16], 'ro') # r=Red, o=Ohs(dots)
plt.plot([1,2,3,4], [1,4,9,16]) # Add lines, Z painted, so on top of red dots.
plt.plot([1.5,2.5,3.5,4.5], [16,9,4,1], 'b^') # b=Blue, ^=Tris

# Normal math functions work.
X= [x/60.0 for x in range(600)]
plt.plot(X,[8*math.cos(5*x) for x in X])

# Numpy arrays are good.
x= np.arange(0,6,.01)
y= 10 * np.sin(x*10)
plt.plot(x,y,'g--') # g=Green, --=Dashed

# Output.
plt.savefig('plottest.svg',format="svg") # "png" is good too.
plt.show() # Seems to clear the image too, so save it first.

import numpy as np
import matplotlib.pyplot as plt

fig = plt.figure()
ax = fig.add_subplot(2, 1, 1)
ax.imshow(np.random.random((10,10)))
ax.autoscale(False)
ax2 = fig.add_subplot(2, 1, 2, sharex=ax, sharey=ax)
ax2.imshow(np.random.random((10,10)))
ax2.autoscale(False)
plt.show()

#!/usr/bin/python
import matplotlib.pyplot as plt
with open('cpi','r') as f: # Open file for reading.
    data= [l.strip().split(' ') for l in f] # Make list of lists.
datelabels= [i[0] for i in data]   # Labels in first column.
for i,d in enumerate(datelabels):  # Remove all...
    if (i-1)%12: datelabels[i]= '' # ... but January.
# Data for different plots.
allitems=   [float(i[1]) for i in data]
television= [float(i[2]) for i in data]
software=   [float(i[3]) for i in data]
computers=  [float(i[4]) for i in data]
internet=   [float(i[5]) for i in data]
audio=      [float(i[6]) for i in data]
cameras=    [float(i[7]) for i in data]
# Formatting
plt.title('Cost of Tech Products')
plt.ylabel('BLS CPI')
yN= range(len(datelabels)) # Numeric positions.
plt.xticks(yN,datelabels,rotation=45)
plt.plot(yN,computers,label='Computers')
plt.plot(yN,television,label='TV')
plt.plot(yN,audio,label='Audio')
plt.plot(yN,software,label='Software')
plt.plot(yN,internet,label='Internet')
plt.plot(yN,cameras,label='Cameras')
plt.legend(loc='upper left',ncol=2)
#plt.show()
plt.tight_layout()
plt.savefig('cpi.png',format='png',figsize=(8,18),dpi=100)

# Data looks like this:
#Dec_1997 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0
#Jan_1998 100.2 99.8 101.8 96.9 97.1 100.2 99.4 99.9
#Source:https://www.bls.gov/opub/ted/2015/\
#->  long-term-price-trends-for-computers-tvs-and-related-items.htm