Prevent axes from being in scientific notation (powers of 10) using matplotlib in Python on semilogy plot

Question

I've read here (How to prevent numbers being changed to exponential form in Python matplotlib figure) and here (Matplotlib: disable powers of ten in log plot) and tried their solutions to no avail.

How can I convert my y-axis to display normal decimal numbers instead of scientific notation? Note this is Python 3.5.2.

Here's my code:

#Imports:
import matplotlib.pyplot as plt

possible_chars = 94
max_length = 8
pw_possibilities = [] 
for num_chars in range(1, max_length+1):
    pw_possibilities.append(possible_chars**num_chars)

x = range(1, max_length+1)
y = pw_possibilities 

#plot 
plt.figure()
plt.semilogy(x, y, 'o-')
plt.xlabel("num chars in password")
plt.ylabel("number of password possibilities")
plt.title("password (PW) possibilities verses # chars in PW")
plt.show()

Answer 1

How do you want to display 10^15? As 1000000000000000 ?! The other answer applies to the default formatter, when you switch to log scale a LogFormatter is used which has a different set of rules. You can switch back to ScalarFormatter and disable the offset

import matplotlib.pyplot as plt
import matplotlib.ticker as mticker
plt.ion()

possible_chars = 94
max_length = 8
pw_possibilities = [] 
for num_chars in range(1, max_length+1):
    pw_possibilities.append(possible_chars**num_chars)

x = range(1, max_length+1)
y = pw_possibilities 

#plot 
fig, ax = plt.subplots()
ax.semilogy(x, y, 'o-')
ax.set_xlabel("num chars in password")
ax.set_ylabel("number of password possibilities")
ax.set_title("password (PW) possibilities verses # chars in PW")
ax.yaxis.set_major_formatter(mticker.ScalarFormatter())
ax.yaxis.get_major_formatter().set_scientific(False)
ax.yaxis.get_major_formatter().set_useOffset(False)
fig.tight_layout()
plt.show()

See http://matplotlib.org/api/ticker_api.html for all of the available Formatter classes.

(this image is generated off of the 2.x branch, but should work on all recent version of mpl)