Re: [Numpy-discussion] Optimize Floyd-Wallshall algorithm with Numpy

2010-11-06 Thread John Salvatier
The difference is that dis[k,:] eliminates the first dimension since you are using a single number as an index, but dis[k:k+1,:] does not eliminate that dimension. On Sat, Nov 6, 2010 at 1:24 PM, wrote: > On Sat, Nov 6, 2010 at 4:14 PM, K. Sun wrote: >> Thanks a lot. It works! I modify the code

Re: [Numpy-discussion] Optimize Floyd-Wallshall algorithm with Numpy

2010-11-06 Thread josef . pktd
On Sat, Nov 6, 2010 at 4:14 PM, K. Sun wrote: > Thanks a lot. It works! I modify the code as follows and it runs > at fast as matlab. By numpy's convention, the input and output > are all ndarrays. 'route' has to be a (1xN) matrix to produce a > square matrix in 'route + route.T'. If you read my

Re: [Numpy-discussion] Optimize Floyd-Wallshall algorithm with Numpy

2010-11-06 Thread K. Sun
Thanks a lot. It works! I modify the code as follows and it runs at fast as matlab. By numpy's convention, the input and output are all ndarrays. 'route' has to be a (1xN) matrix to produce a square matrix in 'route + route.T'. def floyd( dis ): '''Floyd-Wallshall algorithm for shortest path

Re: [Numpy-discussion] Optimize Floyd-Wallshall algorithm with Numpy

2010-11-06 Thread josef . pktd
On Sat, Nov 6, 2010 at 3:28 PM, K. Sun wrote: > Hello, > > I wrote the following code with numpy to implement the Floyd-Wallshall > algorithm to compute the pair-wise shortest path in a undirected weighted > graph. It is really slow when N ~ 10k, while the same implementation in > matlab is much f

[Numpy-discussion] Optimize Floyd-Wallshall algorithm with Numpy

2010-11-06 Thread K. Sun
Hello, I wrote the following code with numpy to implement the Floyd-Wallshall algorithm to compute the pair-wise shortest path in a undirected weighted graph. It is really slow when N ~ 10k, while the same implementation in matlab is much faster. I am sorry I don't want to run it again to present