Re: Python arrays and sting formatting options

Ivan Reborin wrote:
Hello everyone,

I was wondering if anyone here has a moment of time to help me with 2
things that have been bugging me.

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 ?

2. I've read the help on the next one but I just find it difficult
understanding it.
I have;
a=2.000001
b=123456.789
c=1234.0001

How do you print them with the same number of decimals ?
(eg. 2.000, 123456.789, 1234.000)
and how do you print them with the same number of significant
decimals?
(eg. 2.000001, 123456.7, 1234.000 - always 8 decimals) ?


Is something like this possible (built-in) in python ?

Really grateful for all the help and time you can spare.

--
Ivan


I'm not sure if this is applicable to your multi-dimensional list problem... but it sounded a bit sudoku like (with row, columns and groups) so I thought I'd share a bit of code of developed in regards to solving sudoku puzzles...

Given a list of 9 list elements, each with nine elements (lets call it sudoku_grid), the following list comprehensions produce lists of indexes into sudoku grid

vgroups = [[(x,y) for y in xrange(9)] for x in xrange(9)]
hgroups = [[(x,y) for x in xrange(9)] for y in xrange(9)]
lgroups = [[(x,y) for x in xrange(a,a+3) for y in xrange(b,b+3)]
for a in xrange(0,9,3) for b in xrange(0,9,3)]

where sudoku_grid[y][x] yields the value at position (x,y), assuming the top left corner is indexed as (0,0)

HTH
.

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