Help with Printing Matrix Grid

[okcomputer24]

I am wanting to print a matrix grid which is derived from a list of lists. The grid should look as follows:

Col 0 Col 1 Col 2

Row 0 1 2 3
Row 1 4 5 6
Row 2 7 8 9

However, I can't figure out how to print the lists without the [ ] around them. My code so far is as shown:

lol = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]

for i in range(0,len(lol )):
print " "*5 +"Col", i,
print "\n"
for i in range(0,len(lol )):
print "Row",i,lol[i]

Any suggestions or advice would be greatly appreciated. Thanks!

[elcron]

I am wanting to print a matrix grid which is derived from a list of lists. The grid should look as follows:

Col 0 Col 1 Col 2

Row 0 1 2 3
Row 1 4 5 6
Row 2 7 8 9

However, I can't figure out how to print the lists without the [ ] around them. My code so far is as shown:

lol = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
 
for i in range(0,len(lol)):
        print " "*5 +"Col", i,
print "\n"
for i in range(0,len(lol)):
        print "Row",i,lol[i]
 

Any suggestions or advice would be greatly appreciated. Thanks!

You can access nested lists the same you could try something like li[i][j] but the following is more scalable

if True:
    lol = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
 
    print "Columns %s"%( " ".join([str(j) for j in range(len(lol[0])]) )
    for i in range(0,len(lol)):
        print " Row %s: %s"%(i, " ".join( [str(j) for j in lol[i]]))
 

[bvdet]

The following uses a neat function that I picked up on this site from a tip by Bartonc. I haven't seen Bartonc in a while.

def columnize(word, width, align='Left'):
    nSpaces = width - len(word)
    if nSpaces < 0:
        nSpaces = 0
    if align == 'Left':
        return word + (" " * nSpaces)
    if align == 'Right':
        return (" " * nSpaces) + word
    return (" " * (nSpaces/2)) + word + (" " * (nSpaces-nSpaces/2))
 
num = int(raw_input('Gimme a starting int: '))
n = int(raw_input('Matrix size: '))
 
listofLists = [[i+j for i in range(num,num+n)] for j in range(0,n*n,n)]
 
column = 7
 
print
print '%s%s' % (columnize('Row/Column |', column*2, 'Right'), \
                '|'.join([columnize('Col %d' % i, column, 'Center') \
                          for i in range(len(listofLists[0]))]))
spaces = sum([column+1 for i in range(len(listofLists[0]))])+column*2
print '='*spaces
for i, item in enumerate(listofLists):
    print '%s%s' % (columnize('Row %d |' % i, column*2, 'Right'), \
                    '|'.join([columnize(str(num), column, 'Center') \
                              for num in item]))

Output:

>>> 
  Row/Column | Col 0 | Col 1 | Col 2 
======================================
       Row 0 |   1   |   2   |   3   
       Row 1 |   4   |   5   |   6   
       Row 2 |   7   |   8   |   9   

[okcomputer24]

Being a new user of Python I never considered joining a for loop. Thanks for your help.