CODEWITHSUNDEEP
pythonnumpymatplotlib
MaksymMO
MaksymMO

Reputation: 45

error in strpdate2num converter in matplotlib

I am trying to read from file a datetime string followed by some data. It provide error. I reduced it to following task which produces error 

import numpy as np
from matplotlib.dates import strpdate2num
from io import StringIO 

d = StringIO(u'16-03-13 20:13:55')
date = np.loadtxt(d, converters={0:strpdate2num('%y-%m-%d %H:%M:%S')})
date

provides following error:

ValueError: time data '16-03-13' does not match format '%y-%m-%d %H:%M:%S'

execution of separate parts works well

d = StringIO(u'16-03-13')
date = np.loadtxt(d, converters={0:strpdate2num('%y-%m-%d')})
date

gives me 

array(736036.0)

the piece alone with time works also well

d = StringIO(u"20:13:55")
date= np.loadtxt(d, delimiter=' ', unpack=True, converters={0: strpdate2num('%H:%M:%S')})
date

gives 

array(693596.8429976852)

What I am doing wrong?

Upvotes: 0

Views: 1578

Answers (1)

tmdavison
tmdavison

Reputation: 69136

The problem is because np.loadtxt is trying to split your string up into two components, as its default delimiter is a space and you have a space in your string.

If you change the delimiter to anything else, this will work, for example:

date = np.loadtxt(d, converters={0:strpdate2num('%y-%m-%d %H:%M:%S')}, delimiter=',')

print date
# 736036.842998

Of course, if you have data after your string, and your delimiter is a space between the datetime string and the data, you may need to read the date and time as two separate strings, then join them together after.

Upvotes: 1

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