How to plot the number of times each element is in a list [closed]

Question

I'm trying to do something slightly that I wouldn't think would be hard, but I can't figure out how to get python/matplotlib/pylab to do.

Given an input, I want a histogram that shows me the number of times each element appears.

Given a list

x=range(10)

I'd like output that has a single bar, y value of 10, equal to x=1, no other graphs.

given a list

x=range(10)
x.append(1)

I'd like the output to have two bars, a y value of 9 for x=1, a y value of 1 for x=2. How can I do this?

Answer 1

This code gives you a histogram like the one you like:

import matplotlib.pyplot as plt
import numpy as np
y = np.array([0,1,2,3,4,5,6,7,8,9,1])
plt.hist(y);
plt.show()

Answer 2

Something like this? This code uses a Counter to count the number of instances that an object occurs in an array (in this case counting the number of times an integer is in your list).

import matplotlib.pyplot as plt
from collections import Counter

# Create your list
x = range(10)
x.append(1)

# Use a Counter to count the number of instances in x
c = Counter(x)

plt.bar(c.keys(), c.values())
plt.show()