> Pixels - just ones and zeroes? Pack them as integers and apply the
> right shift operator:
> i>>=1
But you have to remember to overflow right hand ones into
the next integer if there are more than 32 bits...
Although Python long integers migfht work, dunno what the
speed of shifting a long i
I don't know about a large calculation time, but this seems to work:
>>> def rightshift(a):
ia = a[:]
for i in range(len(ia)-1,0,-1):
if ia[i-1] == 1 and ia[i]!=1:
ia[i]=1
ia[i-1]=0
return ia
Hello!
> > I want to move all the 1's move to the right, 1 index at a time,
> > preserving any spacing.
[ snip ]
> > I'm starting to think I'm going to have to go Cpp for this kind of
> > direct pixel tweaking stuff.
> > (640x480 (let alone 1024x768) is a lot of pixels to run through a for...
>
This code will work.
a=[1,0,0,0,0,1,1,1,0,1,1,0,1,0]
shorta=a[:]
while 0 in shorta:
shorta.reverse()
shorta.remove(0)
shorta.reverse()
print [0,]*(len(a)-len(shorta))+shorta
result=[0,]*(len(a)-len(shorta))+shorta
Juan Shen
在 2005年1月5日 星期三 11:44，Liam Clarke 写道：
> Sorry rephrase
> > I want to move all the 1's move to the right, 1 index at a time,
> > preserving any spacing.
>
> So you want to insert a zero at the front and delete the first
> zero from the back? That doesn't require iterating over all
> the entries just enough to find the first zero...
Playing with this
> I want to move all the 1's move to the right, 1 index at a time,
> preserving any spacing.
So you want to insert a zero at the front and delete the first
zero from the back? That doesn't require iterating over all
the entries just enough to find the first zero...
> [1,0,0,0,0,1,1,1,0,1,1,0,1,
Sorry rephrase -
So I have a list -
[0,0,0,0,0,1,1,1,0,1,1,0,1,0]
I want to move all the 1's move to the right, 1 index at a time,
preserving any spacing.
i.e.
[1,0,0,0,0,1,1,1,0,1,1,0,1,0]
[0,1,0,0,0,0,1,1,1,0,1,1,0,1]
[0,0,1,0,0,0,0,1,1,1,0,1,1,1]
[0,0,0,1,0,0,0,0,1,1,1,1,1,1]
[0,0,0,0
Hi all,
Just playing with Pygame, attempting to build a version of Scorched
Earth if you remember it.
I want to represent dirt, and so far I've come up with using a surface array -
0 644120 64412 64412
00 64412 64412 64412
0 644120
