Which version of matplotlib are you using? Which version of python are you
using? On what OS?

On Wed, Feb 18, 2015 at 3:49 PM, keigolee514 [email protected]
wrote:

from future import print_function
from matplotlib.dates import strpdate2num
#from matplotlib.mlab import load
import numpy as np
from pylab import figure, show
import matplotlib.cbook as cbook

datafile = cbook.get_sample_data('msft.csv', asfileobj=False)
print('loading', datafile)

dates, closes = np.loadtxt(
datafile, delimiter=',',
converters={0:strpdate2num('%d-%b-%y')},
skiprows=1, usecols=(0,2), unpack=True)

fig = figure()
ax = fig.add_subplot(111)
ax.plot_date(dates, closes, '-')
fig.autofmt_xdate()
show()

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#4126.

Matplotlib: 1.8.2
Python: 3.4
OS: Windows 8 64-bit

Thank you!

1.8.2? Are you a time traveler?

On Wed, Feb 18, 2015 at 4:05 PM, keigolee514 [email protected]
wrote:

Matplotlib: 1.8.2
Python: 3.4
OS: Windows 8 64-bit

Thank you!

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#4126 (comment)
.

sorry, 1.4.2...

The problem is that numpy passes a byte string to the converter instead of a string. In python 2, since bytes and str are equivalent it does not matter. For python 3, however, this results in an error as strpdate2num passes it to the standard library's strptime which only expects a string.

We could add another converter for byte input to the dates module. Not sure if it really would get enough use to make sense in adding, however.

@keigolee514, you could use the following to get it working for you:

from __future__ import print_function
from matplotlib.dates import strpdate2num
#from matplotlib.mlab import load
import numpy as np
from pylab import figure, show
import matplotlib.cbook as cbook

def bytespdate2num(fmt, encoding='utf-8'):
    strconverter = strpdate2num(fmt)
    def bytesconverter(b):
        s = b.decode(encoding)
        return strconverter(s)
    return bytesconverter


datafile = cbook.get_sample_data('msft.csv', asfileobj=False)
print('loading', datafile)

dates, closes = np.loadtxt(
    datafile, delimiter=',',
    converters={0:bytespdate2num('%d-%b-%y')},
    skiprows=1, usecols=(0,2), unpack=True)

fig = figure()
ax = fig.add_subplot(111)
ax.plot_date(dates, closes, '-')
fig.autofmt_xdate()
show()

Closed by #4153

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

date,open,close=np.loadtxt('000001.csv',delimiter=',',converters={0:mdates.strpdate2num('%m/%d/%Y')},skiprows=1,usecols=(0,1,4),unpack=True)

plt,plot(date,open)

for the same problem.
strptime() argument 0 must be str, not <class 'bytes'>

ask for help

@haunledeshuchang This sort of question is best handled on the mailing list ([email protected] you will need to join the list to post un-moderated. We try to keep the issues for bug reports or feature requests.

seems I have same issue as @haunledeshuchang
Python 3.6.4
matplotlib==2.1.2

Bdw How does the function bytesconverter(b): gets called in,

def bytespdate2num(fmt, encoding='utf-8'):
strconverter = strpdate2num(fmt)
def bytesconverter(b):
s = b.decode(encoding)
return strconverter(s)
return bytesconverter