How to use python numpy.savetxt to write strings and float number to an ASCII file?
I have a set of lists that contain both strings and float numbers, such as:
import numpy as num NAMES = num.array(['NAME_1', 'NAME_2', 'NAME_3']) FLOATS = num.array([ 0.5 , 0.2 , 0.3 ]) DAT = num.column_stack((NAMES, FLOATS))
I want to stack these two lists together and write them to a text file in the form of columns; therefore, I want to use numpy.savetxt (if possible) to do this.
num.savetxt('test.txt', DAT, delimiter=" ")
When I do this, I get the following error:
>>> num.savetxt('test.txt', DAT, delimiter=" ") Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/Library/Python/2.7/site-packages/numpy-1.8.0.dev_9597b1f_20120920-py2.7-macosx-10.8-x86_64.egg/numpy/lib/npyio.py", line 1047, in savetxt fh.write(asbytes(format % tuple(row) + newline)) TypeError: float argument required, not numpy.string_
The ideal output file would look like:
NAME_1 0.5 NAME_2 0.2 NAME_3 0.3
How can I write both strings and float numbers to a text file, possibly avoiding using csv ( I want to make if readable for other people )? Is there another way of doing this instead of using numpy.savetxt?
You have to specify the format (
fmt) of you data in
savetxt, in this case as a string (
num.savetxt('test.txt', DAT, delimiter=" ", fmt="%s")
The default format is a float, that is the reason it was expecting a float instead of a string and explains the error message.