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Re: CSV to matrix array

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  Re: CSV to matrix array Jean-Michel Pichavant <jeanmichel@sequans.com> - 2013-04-12 19:23 +0200
    Re: CSV to matrix array Ana Dionísio <anadionisio257@gmail.com> - 2013-04-12 10:29 -0700
      Re: CSV to matrix array Dave Angel <davea@davea.name> - 2013-04-12 13:46 -0400
      Re: CSV to matrix array Javier Miranda <javier@codecoa.com> - 2013-04-12 17:45 -0500
      Re: CSV to matrix array cantorp@gmail.com - 2013-04-13 10:06 -0700
      Re: CSV to matrix array cantorp@gmail.com - 2013-04-13 10:06 -0700
    Re: CSV to matrix array Ana Dionísio <anadionisio257@gmail.com> - 2013-04-12 10:29 -0700

#43472 — Re: CSV to matrix array

----- Original Message -----
> Hello!
> 
> I have a CSV file with 20 rows and 12 columns and I need to store it
> as a matrix. I already created an array with zeros, but I don't know
> how to fill it with the data from the csv file. I have this script:
> 
> import numpy
> from numpy import array
> from array import *
> import csv
> 
> input = open('Cenarios.csv','r')
> cenario = csv.reader(input)
> 
> array=numpy.zeros([20, 12])
> 
> 
> I know I have to use for loops but I don't know how to use it to put
> the data the way I want. Can you help me?
> 
> Thanks!

did you try 

array = numpy.array(list(cenario))

?

JM



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#43473

That only puts the data in one column, I wanted to separate it. 

For example:
data in csv file:

1 2 3 4 5
7 8 9 10 11
a b c d e

I wanted an array where I could pick an element in each position. In the case above if I did print array[0][3] it would pick 4  

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#43476

On 04/12/2013 01:29 PM, Ana Dionísio wrote:
> That only puts the data in one column, I wanted to separate it.
>
> For example:
> data in csv file:
>
> 1 2 3 4 5
> 7 8 9 10 11
> a b c d e
>
> I wanted an array where I could pick an element in each position. In the case above if I did print array[0][3] it would pick 4
>

I know nothing about numpy.

How about something like:
     import csv
     myreader = csv.reader(....)
     mylist = list(myreader)


Presumably you can fill in the details.  Anyway, I think this will give 
you a list of lists, and perhaps you can convert that to a numpy array, 
if you really need one of those.


-- 
DaveA

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#43490

[Multipart message — attachments visible in raw view] — view raw

Keep the flattened data array others suggested, and then just split it like
this: *(replace `example_data`, `_array`, and `columns`)*

>>> example_data = range(15)

>>> split_array = lambda _array, colums: \

. . .        [_array[i:i + colums] for i in \

. . .                xrange(0, len(_array), colums)]

 >>> print split_array(example_data, 5)

[[0, 1, 2, 3, 4], [5, 6, 7, 8, 9], [10, 11, 12, 13, 14]]

Gist <https://gist.github.com/anonymous/f9064e4c8790ae037ec6>

What do you guys think?


On Fri, Apr 12, 2013 at 12:46 PM, Dave Angel <davea@davea.name> wrote:

> On 04/12/2013 01:29 PM, Ana Dionísio wrote:
>
>> That only puts the data in one column, I wanted to separate it.
>>
>> For example:
>> data in csv file:
>>
>> 1 2 3 4 5
>> 7 8 9 10 11
>> a b c d e
>>
>> I wanted an array where I could pick an element in each position. In the
>> case above if I did print array[0][3] it would pick 4
>>
>>
> I know nothing about numpy.
>
> How about something like:
>     import csv
>     myreader = csv.reader(....)
>     mylist = list(myreader)
>
>
> Presumably you can fill in the details.  Anyway, I think this will give
> you a list of lists, and perhaps you can convert that to a numpy array, if
> you really need one of those.
>
>
> --
> DaveA
> --
> http://mail.python.org/**mailman/listinfo/python-list<http://mail.python.org/mailman/listinfo/python-list>
>



-- 
Javier Miranda
Mobile: +52 333 129 20 70

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#43526

Dear Ana,

your example data could be transformed into a matrix with

>>>import csv
>>>rows = csv.reader(open("your_data_file.csv"), delimiter=" ")
>>>array = [row for row in rows]
>>>array[0][3]
4

HTH
Paolo

Am Freitag, 12. April 2013 19:29:05 UTC+2 schrieb Ana Dionísio:
> That only puts the data in one column, I wanted to separate it. 
> 
> 
> 
> For example:
> 
> data in csv file:
> 
> 
> 
> 1 2 3 4 5
> 
> 7 8 9 10 11
> 
> a b c d e
> 
> 
> 
> I wanted an array where I could pick an element in each position. In the case above if I did print array[0][3] it would pick 4

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#43527

Dear Ana,

your example data could be transformed into a matrix with

>>>import csv
>>>rows = csv.reader(open("your_data_file.csv"), delimiter=" ")
>>>array = [row for row in rows]
>>>array[0][3]
4

HTH
Paolo

Am Freitag, 12. April 2013 19:29:05 UTC+2 schrieb Ana Dionísio:
> That only puts the data in one column, I wanted to separate it. 
> 
> 
> 
> For example:
> 
> data in csv file:
> 
> 
> 
> 1 2 3 4 5
> 
> 7 8 9 10 11
> 
> a b c d e
> 
> 
> 
> I wanted an array where I could pick an element in each position. In the case above if I did print array[0][3] it would pick 4

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#43474

That only puts the data in one column, I wanted to separate it. 

For example:
data in csv file:

1 2 3 4 5
7 8 9 10 11
a b c d e

I wanted an array where I could pick an element in each position. In the case above if I did print array[0][3] it would pick 4  

[toc] | [prev] | [standalone]

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