Pyplot/Matplotlib: Binary data with strings on x-axis

Question

I know it's such a basic thing, but due to ridiculous time constraints and the severity of the situation I'm forced to ask something like this:

I've got two arrays of 160 000 entries. One contains strings(names I need to use), the other contains corresponding 1's and 0's.

I'm trying to make a simple "step" graph in pyplot with the array of names along the X-axis and 0 and 1 along the Y-axis.

I have this currently:

import numpy as np
import matplotlib.pyplot as plt
data = [1, 2, 4, 5, 9]
bindata = [0,1,1,0,1,1,0,0,0,1]
xaxis = np.arange(0, data[-1] + 1)
yaxis = np.array(bindata)
plt.step(xaxis, yaxis)
plt.xlabel('Filter Degree Combinations')
plt.ylabel('Negative Or Positive')
plt.title("Car 1")
#plt.savefig('foo.png') #For saving
plt.show()

It gives me this: enter image description here

But I want something like this: enter image description here

I cobbled the code together from some examples, tutorials and stackoverflow questions, but I run into "ValueError: x and y must have same first dimension" so often that I'm not getting anywhere when I try to experiment my way forward.

• wwii: Just ensure length of xaxis and yaxis are equal before plotting.
• wwii: You should always include the complete Traceback.

Answer 1

You can achieve the desired plot by specifying the tick labels and their positions on the x-axis using plt.xticks. The first argument range(0, 10, 2) is the positions followed by the strings

import numpy as np
import matplotlib.pyplot as plt
data = [1, 2, 4, 5, 9]
bindata = [0,1,1,0,1,1,0,0,0,1]
xaxis = np.arange(0, data[-1] + 1)
yaxis = np.array(bindata)
plt.step(xaxis, yaxis)
xlabels = ['Josh', 'Anna', 'Kevin', 'Sophie', 'Steve'] # <-- specify tick-labels
plt.xlabel('Filter Degree Combinations')
plt.ylabel('Negative Or Positive')
plt.title("Car 1")
plt.xticks(range(0, 10, 2), xlabels) # <-- assign tick-labels
plt.show()

enter image description here