[GRASS-dev] [bug #2969] can wxPython GUI handle order of options for v.type and alike?

Maciej Sieczka tutey at o2.pl
Tue May 29 16:39:51 EDT 2007


Maciej Sieczka wrote:
> Hamish wrote:
>> Maciej Sieczka wrote:
>>> Hamish wrote:
>>>> Maciej Sieczka wrote:
>>>>> Is:
>>>>>
>>>>> $ v.type from=point to=centroid; v.type from=line to=boundary;
>>>>>
>>>>> as fast as:
>>>>>
>>>>> $ v.type type=point,centroid,line,boundary
>>>>>
>>>>> ?
>>>> No. But it's a very quick operation, so twice as long is still not
>>>> very long.
>>> ???
>>>
>>> This is a regression. If I was to suggest something I'd suggest
>>> reverting this change.
>>
>> two points:
>>
>> 1) this hasn't been enacted anywhere in the (active) code. This is
>> just proposal/preparation for GRASS 7. v.type in 6.3 still does type=,,,
> 
> Yes I know.
> 
>> 2) It is a balance of cost vs benefit. To me, clarity and ease of use
>> is more important than ability to do two things at once. The speed hit
>> is minimal (I expect you could retype a massive 1 million point LIDAR
>> map in a second or two);
> 
> OK. So we need a benchmark.

Done as follows:

$ v.info -t mlns
nodes=1000000
points=1000000
lines=999000
boundaries=0
centroids=0
areas=0
islands=0
faces=0
kernels=0
primitives=1999000
map3d=0

$ time v.type in=mlns out=mlns_type_once type=point,centroid,line,boundary

real    6m37.459s
user    6m12.191s
sys     0m23.673s


$ time `v.type in=mlns out=mlns_type_first type=point,centroid; v.type
in=mlns_type_first out=mlns_type_second type=point,centroid`

real    6m26.522s
user    5m34.141s
sys     0m45.615s

Actaully, the latter method seems a bit faster. No worries in that
case. Sorry for the fuss Hamish. Hope you don't mind :).

Maciek




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