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How to input data in SAGE and deal with them

asked 2013-11-02 21:20:45 +0100

Li Yutong gravatar image

updated 2013-11-03 00:16:50 +0100

vdelecroix gravatar image

I wish to calculate the width of the certain polytopes, the data for these polytopes can be found here (please click "K3/3d" on the left, and then click "list of all 4319" on the top of new page, for some reason, I could not cite the exact URL).

For example, the first one is

3 4 M:5 4 N:35 4 Pic:19 Cor:0

1    0    0   -1
0    1    0   -1
0    0    1   -1

However, only the number in the matrix will be used in the calculation. My questions are:

(1) How to input these data in SAGE (I use a windows system, and run Virtualbox for SAGE)?

(2) How to use sage to deal with each matrix?

For each of matrix, I have a program as the follows

sage: m = matrix(ZZ, [[1,0,0,-1],
....:        [0,1,0,-1],
....:        [0,0,1,-1]])
sage: p = LatticePolytope(m)
sage: d = p.distances()
sage: l = p.nfacets()
sage: for i in range(l):
....:     max(d.row(i))

After input the data, how to let sage use the same program deal with each matrix?

Thank you very much for your help!!!

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Comments

Maybe also the answers in this (http://ask.sagemath.org/question/1842/how-to-plot-data-from-a-file#2705) related questions are helpful.

twch gravatar imagetwch ( 2013-11-03 11:23:21 +0100 )edit

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answered 2013-11-03 03:25:13 +0100

ndomes gravatar image

Copy and paste the data from "K3/3d" to a text file. Upload that file to your worksheet (I use Sage Notebook). (I name the file 'k3_d3_data.txt')

Open the file in your worksheet. Now you can iterate through the lines and convert the appropriate lines to matrices.

data_file = file(DATA+'k3_d3_data.txt','r')   
matrix_list = []    
while True:
    try: 
        data_file.next()
    except StopIteration:
        break
    row1 = [int(z) for z in data_file.next().split()]
    row2 = [int(z) for z in data_file.next().split()]
    row3 = [int(z) for z in data_file.next().split()]
    matrix_list.append(matrix(ZZ,[row1,row2,row3]))  

for M in matrix_list:
    print M
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@ndomes, Thank you very very much!!! You answer is fabulous, I know how to do it now!!!

Li Yutong gravatar imageLi Yutong ( 2013-11-03 13:59:04 +0100 )edit

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Asked: 2013-11-02 21:20:45 +0100

Seen: 698 times

Last updated: Nov 03 '13