Python data types

Question

I wrote a script to take the data files that are in the columns and put them in depending on which column wants to look. Well, I noticed that the plots look crazy and have all the wrong numbers, because python ignores exponential.

My numbers are in the format: 1.000000E + 1 OR 1.000000E-1

What is dtype? I am using numpy.genfromtxt to import with dtype = float. I know that there are all types of dtypes that you can enter, but I cannot find an exhaustive list of options and examples.

Thank.

Here is an example of my input (these spaces are tabs):

Time stamp T1_ModBt T2_90Bend T3_InPE T5_Stg2Rfrg
5:22 AM 2.115800E + 2 1.400000E + 0 1.400000E + 0 3.035100E + 1
5:23 AM 2.094300E + 2 1.400000E + 0 1.400000E + 0 3.034800E + 1
5:24 AM 2.079300E + 2 1.400000E + 0 1.400000E + 0 3.031300E + 1
5:25 AM 2.069500E + 2 1.400000E + 0 1.400000E + 0 3.031400E + 1
5:26 AM 2.052600E + 2 1.400000E + 0 1.400000E + 0 3.030400E + 1
5:27 AM 2.040700E + 21.400000E + 0 1.400000E + 0 3.029100E + 1

Update I understood at least part of the reason why what I am doing is not working. Still don't know how to define dtypes the way I want.

import numpy as np

file = np.genfromtxt('myfile.txt', usecols = (0,1), dtype = (str, float), delimiter = '\t')

Returns an array of rows for each column. How can I say that I want column 0 to be str and all other columns to be floating?

Answer 1

In [55]: type(1.000000E+1)
Out[55]: <type 'float'>

What your source data looks like, it is possible that it is in the wrong input format, but it is also sure that it is quite easy to convert it to the correct format.

Answer 2

The numbers in the form 1.0000E+1can be parsed using float(), so I'm not sure what the problem is:

>>> float('1.000E+1')
10.0

Answer 3

, python.

1.00000E + 1 1.0 ^ 1, float.