I'm trying to make a column graph where the x-axis corresponds to distance. My current data looks like:
dist intensity:
0 1521
10 176
17 47
20 397
So at 10 units along the x-axis I was a bar 176 high, at 17 units along a bar 47 high, etc etc. Any easy methods? A standard bar graph code doesn't seem to have this 'easily' in built as the bars aren't evenly spaced...
Matplotlib's bar function puts your bars where you tell it to using a set of x-coordinates provided:
import pylab
import matplotlib.pyplot as plt
import numpy as np
dist = [0,10,17,20]
intensity = [1521, 176, 47, 397]
fig, ax = plt.subplots()
ax.bar(dist, intensity, align='center')
plt.show()
I believe that an easy solution is to create an array where the indices are the x-values (dist) and the values are the y-values (intensity). If you have more data, a more pythonic way to populate the array can be determined, but for now this should yield the results you need - see below.
import pylab
import matplotlib.pyplot as plt
import numpy as np
plt.clf()
N = 21
data = (1521, 0., 0., 0., 0., 0., 0., 0., 0., 0., 176., 0., 0., 0., 0., 0., 0., 47., 0., 0., 397. )
ind = np.arange(N)
width = 0.2
plt.subplot(111)
plt.bar(ind, data, width, color='purple')
plt.xlabel('Distance')
plt.ylabel('Intensity')
plt.ylim([0., 1550.])
plt.xlim([-1., 22.])
plt.show()
pyplot.barhas an array of left coordinates and height coordinates as input (and a width identical for every bar), which should do what you want.