Python arrays and sting formatting options
Marc 'BlackJack' Rintsch
bj_666 at gmx.net
Tue Sep 30 18:11:11 CEST 2008
On Tue, 30 Sep 2008 10:57:19 -0500, Grant Edwards wrote:
> On 2008-09-30, Peter Pearson <ppearson at nowhere.invalid> wrote:
>> On Tue, 30 Sep 2008 00:04:18 +0200, Ivan Rebori wrote:
>>>
>>> 1. Multi dimensional arrays - how do you load them in python For
>>> example, if I had:
>>> -------
>>> 1 2 3
>>> 4 5 6
>>> 7 8 9
>>>
>>> 10 11 12
>>> 13 14 15
>>> 16 17 18
>>> -------
>>> with "i" being the row number, "j" the column number, and "k" the ..
>>> uhmm, well, the "group" number, how would you load this ?
>>>
>>> If fortran90 you would just do:
>>>
>>> do 10 k=1,2
>>> do 20 i=1,3
>>>
>>> read(*,*)(a(i,j,k),j=1,3)
>>>
>>> 20 continue
>>> 10 continue
>>>
>>> How would the python equivalent go ?
>
> You would drag yourself out of the 1960s, install numpy, and then do
> something like this:
>
> a = read_array(open("filename.dat","r"))
In [64]: a = numpy.fromfile('test.txt', dtype=int, sep=' ')
In [65]: a
Out[65]:
array([ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
18])
In [66]: a.reshape(2, 3, 3)
Out[66]:
array([[[ 1, 2, 3],
[ 4, 5, 6],
[ 7, 8, 9]],
[[10, 11, 12],
[13, 14, 15],
[16, 17, 18]]])
Ciao,
Marc 'BlackJack' Rintsch
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