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I'd wanna to read time strings and data from a file but when I used loadtxt i cant read string and numbers at the same time because strings are not float. So i tried using genfromtxt and use delimiter=[]+[]+[] acording the columns that I have, but the string are read like nan. i'd like read the time directly like a time array (date2num, datetime or similar) to be able to plot in matplotlib in the correct form. So, what can i do? I leave a mi list below (Obviously, it's more data):

GOES data for time interval: 20-Feb-2014 00:00:00.000 to 27-Feb-2014 00:00:00.000
Current time: 23-Mar-2014 21:52:00.00

Time at center of bin        1.0 - 8.0 A    0.5 - 4.0 A  Emission Meas           Temp
                              watts m^-2     watts m^-2    10^49 cm^-3             MK
20-Feb-2014 00:00:00.959     4.3439e-006    3.9946e-007        0.30841         10.793
20-Feb-2014 00:00:02.959     4.3361e-006    3.9835e-007        0.30801         10.789
20-Feb-2014 00:00:04.959     4.3413e-006    3.9501e-007        0.30994         10.743
20-Feb-2014 00:00:06.959     4.3361e-006    3.9389e-007        0.30983         10.735
20-Feb-2014 00:00:08.959     4.3361e-006    3.9278e-007        0.31029         10.722
20-Feb-2014 00:00:10.959     4.3387e-006    3.9278e-007        0.31058         10.719
20-Feb-2014 00:00:12.959     4.3361e-006    3.9278e-007        0.31029         10.722
20-Feb-2014 00:00:14.959     4.3361e-006    3.9055e-007        0.31122         10.695
20-Feb-2014 00:00:16.959     4.3334e-006    3.8721e-007        0.31234         10.657
share|improve this question
    
use f = open('path/to/file/here') and then work with split() or regexp –  Tweek Apr 18 at 20:49
    
pymotw.com/2/re <- is nice for regexp –  Tweek Apr 18 at 20:59
    
@Tweek ,A example could be good, thanks –  nandhos Apr 18 at 21:49
    
You might be able to use genfromtxt if you get the dtype argument right. This might also be helpful for reading strings with genfromtxt: stackoverflow.com/questions/12319969/… –  Kyle Neary Apr 18 at 21:53
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1 Answer

up vote 0 down vote

There are probably more elegant solutions using regular expressions, but this works too.

from datetime import datetime

input_file = open("path/filename")
for line in input_file:
    line_parts = line.split()
    if len(line_parts) > 1:
        try:
            # This is now a datetime object
            timestamp = datetime.strptime(line_parts[0] + " " + line_parts[1], "%d-%b-%Y %H:%M:%S.%f")
            # Do stuff with data here (each stored seperately in line_parts list)
            # For instance printing everything.
            print("DateTime Object: " + str(timestamp))
            print("Data: " + str(line_parts[2:]))

            # Cast data to floats for use in arithmetic
            data_point_one = float(line_parts[2])
            print ("data_point_one * 2 = " + str(data_point_one * 2))

        except ValueError:
            # Lines that don't start with a timestamp take this route...
            continue
share|improve this answer
    
That's right, It read the date and time like strings but the numbers (data) is also string now, It must be a float –  nandhos Apr 19 at 3:31
    
You can cast them to floats, I edited the above answer to show you how. –  Aaron Taggart Apr 21 at 14:20
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