I am desperately trying to read and convert a txt file like this:
file.txt
Line,Date Time,Celsius(°C),Humidity(%rh),Dew Point(°C),Serial Number
1,10-06-2013 18:25:00,24.0,48.5,12.5,990121703
2,10-06-2013 18:30:00,24.0,48.0,12.3
3,10-06-2013 18:35:00,23.5,48.5,12.0
4,10-06-2013 18:40:00,23.5,49.0,12.2
5,10-06-2013 18:45:00,23.5,49.0,12.2
6,10-06-2013 18:50:00,23.5,49.0,12.2
7,10-06-2013 18:55:00,23.5,49.0,12.2
...
I have been able to read all numeric values into variables by using:
from pylab import *
from datetime import datetime
fname ='LOG.txt'
n0,DT1,T2,H3,DP4 = genfromtxt(fname,delimiter=',', skip_header=1, skip_footer=0,usecols=(0,1,2,3,4), autostrip=True, unpack=True, invalid_raise=True)
However, the 'date_time' column (her col 1) is not shown as a separate variable nor is there any error message returned.
I would like is to convert things into the to following variables:
n0 = 0 column as 'u4'<br>
DT1 = 1st column converted such that `datetime.strptime('10-06-2013 18:25:01', '%d-%m-%Y %H:%M:%S')`<br>
T2 = 2nd column as 'f4'<br>
H3 = 3rd column as 'f4'<br>
DP4 = 4th column as 'f4'<br>
I have found several examples using, genfromtxt, dtype, and strptime but I got none of them to work for this specific case.
Any suggestions for a newbie?
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EDIT (24-07-2013):
I found a possible solution good enough for what I would like:
from pylab import *
import datetime as DT
def make_date(datestr):
return DT.datetime.strptime(datestr, '%d-%m-%Y %H:%M:%S')
data1 = genfromtxt(fname, delimiter = ',',
skip_header=1,skip_footer=0,usecols = (0,1,2,3,4), # usecols (0..4) is required due to the serial number present in second row only
converters = {'Date':make_date},
names = ('Line', 'Date', 'Temperature', 'Humidity','DewPoint'),
dtype = None,
invalid_raise=True) # dtype = None takes care of all data type but the one sent to converters
# Console output:
print(data1)
print(data1.dtype)
#Temperature Graph:
figure(1)
plot(data1['Date'],data1['Temperature'],'-xb')
grid('on')
ylabel('Temperature (degC)',fontsize=10)
xlabel('Date',fontsize=10)
This returns:
[(1, datetime.datetime(2013, 6, 10, 18, 25), 24.0, 48.5, 12.5)
(2, datetime.datetime(2013, 6, 10, 18, 30), 24.0, 48.0, 12.3)
(3, datetime.datetime(2013, 6, 10, 18, 35), 23.5, 48.5, 12.0) ...,
(12298, datetime.datetime(2013, 7, 23, 11, 10), 23.5, 43.5, 10.4)
(12299, datetime.datetime(2013, 7, 23, 11, 15), 23.5, 43.5, 10.4)
(12300, datetime.datetime(2013, 7, 23, 11, 20), 23.5, 43.5, 10.4)]
[('Line', '<i4'), ('Date', 'O'), ('Temperature', '<f8'), ('Humidity', '<f8'), ('DewPoint', '<f8')]
Now, maybe someone can help me to get to:
n0,DT1,T2,H3,DP4 = genfromtxt(fname,...,unpack=True)
where DT1 consists of:
datetime.datetime(2013, 6, 10, 18, 25)
Thanks for any help
