Python 2.7 NameError: name 'ax1' is not defined

Question

I have Python 2.7 Win 32 and have installed Matplotlib, Numpy, PyParsing, Dateutil. In IDLE I place in the following code:

import matplotlib
import matplotlib.pyplot as plt
import matplotlib.ticker as mticker
import matplotlib.dates as mdates
import numpy as np

def graphRawFX () :
    date=mdates.strpdate2num('%Y%m%d%H%M%S')
    bid, ask = np.loadtxt('GPBUSD1d.txt', unpack=True)
    delimiter=',',
    converters={0:mdates.strpdate2num('%Y%m%d%H%M%S') }
    fig = plt.figure(figsize=(10,7))
    ax1 = plt.subplot2grid((40,40), (0,0), rowspan=40, colspan=40)

    ax1.plot(date,bid)
    ax1.plot(date,ask)

ax1.xaxis.set_major_formatter(mdates.DateFormatter('%Y-%m-%d %H:%M:%S'))

plt.grid(True)
plt.show()

Running the code results in to the following:

Traceback (most recent call last):
  File "C:/Users/Emanuel/Desktop/test.py", line 18, in <module>
    ax1.xaxis.set_major_formatter(mdates.DateFormatter('%Y-%m-%d %H:%M:%S'))
NameError: name 'ax1' is not defined

Any suggestion to editing the code would be helpful.

I've changed my answer to include what your code should look something like — sshashank124, Mar 22 '14 at 14:35

sshashank124 · Accepted Answer · 2014-03-23T00:31:34.803

4

This is because you are calling ax1 outside the method in which it has been defined it. Perhaps you should include that line in the method as well.

or else:

You can create the ax1 object outside the method and then change some of its attributes as necessary in your function by using global ax1

EDIT: It should look something like this:

import matplotlib
import matplotlib.pyplot as plt
import matplotlib.ticker as mticker
import matplotlib.dates as mdates
import numpy as np


ax1 = plt.subplot2grid((40,40), (0,0), rowspan=40, colspan=40)

def graphRawFX (axes1) :

    date=mdates.strpdate2num('%Y%m%d%H%M%S')
    bid, ask = np.loadtxt('GPBUSD1d.txt', unpack=True)
    delimiter=',',
    converters={0:mdates.strpdate2num('%Y%m%d%H%M%S') }
    fig = plt.figure(figsize=(10,7))

    axes1.plot(date,bid)
    axes1.plot(date,ask)

graphRawFX(ax1)

ax1.xaxis.set_major_formatter(mdates.DateFormatter('%Y-%m-%d %H:%M:%S'))

plt.grid(True)
plt.show()

edited Mar 23 '14 at 00:31

answered Mar 22 '14 at 14:23

sshashank124

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Where is the method? I just started programming. – Ben the Pyro Mar 22 '14 at 14:30
Writing it like this 'global ax1.xaxis.set_major_formatter(mdates.DateFormatter('%Y-%m-%d %H:%M:%S'))' gives a syntax error. – Ben the Pyro Mar 22 '14 at 14:31
@BenthePyro, method is the `def graphRawFX():`. Anything that is `def something():` is a method that does a set of actions whenever called. – sshashank124 Mar 22 '14 at 14:32
1

gah! Why are you using global? Just return the axes object if you want to access it outside of the function or pass it in if you want to define it outside. – tacaswell Mar 22 '14 at 16:13
@tcaswell, Is that better now? – sshashank124 Mar 23 '14 at 00:32
You more make an extra figure object, but yes – tacaswell Mar 23 '14 at 00:33

Python 2.7 NameError: name 'ax1' is not defined

1 Answers1