newbie question convert C to python

[doodle4]

How do i handle this piece of code in python:

# define vZero 15
# define vOne 20

unsigned int vTable[Zero][One]

if(vGroup[vZero][vOne] == 0)
{
vGroup[vZero][vOne]--
.....
.....
}

Thanks,
-d4

 

[Paul Rubin]

How do i handle this piece of code in python:

# define vZero 15
# define vOne 20

unsigned int vTable[Zero][One]

if(vGroup[vZero][vOne] == 0)
{
vGroup[vZero][vOne]--
.....
.....
}

Simplest might be with a dictionary:

vGroup = {} # I assume you meant vGroup not vTable
if vGroup[(vZero, vOne)] == 0:
vGroup[(vZero, vOne)] -= 1
.....
.....

 

[Steven Bethard]

How do i handle this piece of code in python:

# define vZero 15
# define vOne 20

unsigned int vTable[Zero][One]

if(vGroup[vZero][vOne] == 0)
{
vGroup[vZero][vOne]--
.....
.....
}

Simplest might be with a dictionary:

vGroup = {} # I assume you meant vGroup not vTable
if vGroup[(vZero, vOne)] == 0:
vGroup[(vZero, vOne)] -= 1
.....
.....

Or, if you like, the parentheses are unnecessary:

vGroup = {}
if vGroup[vZero, vOne] == 0:
vGroup[vZero, vOne] -= 1
.....

This (or the semantically identical version with parentheses) is
definitely the best approach if you expect to have a lot of empty spots
in your table.

STeVe

 

[Adam DePrince]

How do i handle this piece of code in python:

# define vZero 15
# define vOne 20

unsigned int vTable[Zero][One]

if(vGroup[vZero][vOne] == 0)
{
vGroup[vZero][vOne]--
.....
.....
}

Simplest might be with a dictionary:

vGroup = {} # I assume you meant vGroup not vTable
if vGroup[(vZero, vOne)] == 0:
vGroup[(vZero, vOne)] -= 1
.....
.....

Or, if you like, the parentheses are unnecessary:

vGroup = {}
if vGroup[vZero, vOne] == 0:
vGroup[vZero, vOne] -= 1
.....

This (or the semantically identical version with parentheses) is
definitely the best approach if you expect to have a lot of empty spots
in your table.

STeVe

One of the problems I see is the access of uninitialized values. In C,
you *can* read these and it isn't a bad idea if you used memset, calloc
or friends. If I know for sure this will be sparse, I'd reproduce it in
python like this.

vTable = []
for x in xrange( vZero ):
vTable.append( [0,] * vOne )

Now you have a vZero x vOne "array" of zeros. Treat it as you would
such a creature in C ...

vTable[0][0] = 1
or whatever you want to do.

I've seen this question before. Lot in the archives for the subject "2D
array" from Dec 7th 2004 - Dec 10th 2004.

Steven and I recommended roughly opposite solutions at the time

Adam DePrince