[GRASS-user] Re: v.lidar.growing dbmi: Protocol error

[Markus Neteler]

On Wed, Apr 22, 2009 at 11:09 PM, Jack Lonsdale <lonsdale at unbc.ca> wrote:
> If this helps:
> Tried this on Ubuntu 8.10 using both GRASS 6.3 and 6.4 svn

ok - if also in 6.4 present then the "already fixed" argument isn't valid :)

> On Wed, 2009-04-22 at 13:58 -0700, Jack Lonsdale wrote:
>> I am continuing to try and use Grass to process my LiDAR data. However,
>> having completed v.lidar.edgedetect successfully I am unable to complete
>> v.lidar.growing
>>
>> firstly, just to check, the 'first' parameter is the raw dataset?

To my knowledge, no.
AFAIK it is the *last* return which is input to v.lidar.growing.

>> If not how do I create the first return dataset?

You can use v.extract to separate a mixed map into the different
returns (eg based on an attribute identifying the pulse).

>> Secondly, if I run the following:
>> v.lidar.growing input=alrf_subs_edge at lonsdale output=alrf_subs_grow
>> first=alrf_subs_raw tj=0.2 td=0.6
>>
>> All I get is a dbmi:Protocol error, It was impossible to open this
>> table!

Please send the precise error message.
But it may be that the (if so) previous error of using the wrong input
isn't ideally trapped.

>> I have seen someone else had this problem on the list in the past but no
>> definitive solution seemed to occur.

In our book we have successfully used the modules to produce
http://www.grassbook.org/gallery/chapters/s070302f010_cutplanes.jpg
so it worked for us.

Markus