[Tutor] Importing file data into Python arrays

[Alistair McGowan]

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Dear Python Wranglers,
			Being of a scientific bent, I need to handle 
data in arrays to do things like resampling and general calculations. 
I am used to BASIC arrays which I can read data into from other files 
with no problem. However, I am being defeated by the Python 
readline(s) for file import. I can do things within Python OK, such 
as the example below lifted from a help page and modified.

import array
arr=[]
for i in range(5):
     arr.append([])
for j in range(10):
           arr[i].append(i*j*2)
print arr[:]
s = arr [4]
a = s[1]
b = s[2]
print a-b

And I can splice away and reassign values fine.

However, when I try to read in data from a file as shown below, I end 
up with the lines, which I can't  manipulate.

import array
arr=[]
inp = open ("dat.txt","r")
#read line into array
for line in inp.readlines():
	arr.append(line)
print arr [0:3]
which gives

['1 2 3\n', '4 5 6\n', '7 8 9']

as output

I have tried using the  suggested

num = int(string), but I the "/n" can't be dealt with from the space 
delimited simple text file I am using to test this, which is appended 
to this mail.

I have consulted my Python Essential Reference, but I am failing to 
see the way to deal with this. Thanks in advance.
	Cheers,
		Al

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Dear Python Wranglers,

			Being of a scientific bent, I need to handle data in arrays to do
things like resampling and general calculations. I am used to BASIC
arrays which I can read data into from other files with no problem.
However, I am being defeated by the Python readline(s) for file import.
I can do things within Python OK, such as the example below lifted from
a help page and modified.


<fontfamily><param>Geneva</param><bigger>import array

arr=[]

for i in range(5):

    arr.append([])

for j in range(10):

          arr[i].append(i*j*2)

print arr[:]

s = arr [4]

a = s[1]

b = s[2]

print a-b


</bigger></fontfamily>And I can splice away and reassign values fine.


However, when I try to read in data from a file as shown below, I end
up with the lines, which I can't  manipulate.


<fontfamily><param>Geneva</param><bigger>import array

arr=[]

inp = open ("dat.txt","r")

#read line into array

for line in inp.readlines():

	arr.append(line)

print arr [0:3]

</bigger></fontfamily>which gives


['1 2 3\n', '4 5 6\n', '7 8 9'] 


as output


I have tried using the  suggested


num = int(string), but I the "/n" can't be dealt with from the space
delimited simple text file I am using to test this, which is appended
to this mail.


I have consulted my Python Essential Reference, but I am failing to see
the way to deal with this. Thanks in advance.

	Cheers,

		Al

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1 2 3
4 5 6
7 8 9
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Alistair J. McGowan
Department of Geophysical Sciences,
University of Chicago
Chicago
IL 60637

Phone: 773-955-4040 x5-1170 
Fax: 773-702-9505

"Hope is a duty from which paleontologists are exempt."
				David Quammen
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