[GRASS-user] Re: Importing Dems with r.in.xyz

[Markus Metz]

> g.region -p
north:      -49312.5
south:      -74587.5
west:       -3015862.5
east:       -2987512.5
nsres:      25
ewres:      25
rows:       1011
cols:       1134
cells:      1146474


>From the region settings you posted previously, I assume that the 1.
column is north and the 2. is east, so:
> r.in.xyz input=2728AB.ort.grass output=2728AB.ort fs=, x=2 y=1
r.in.xyz complete. 1146370 points found in region.

> r.univar map=2728AB.ort
total null and non-null cells: 1146474
total null cells: 104
Of the non-null cells:
----------------------
n: 1146370
minimum: 1473.52
maximum: 1618.85
range: 145.33
mean: 1519.76
mean of absolute values: 1519.76
standard deviation: 26.6106
variance: 708.125
variation coefficient: 1.75098 %
sum: 1742202717.5849609375

Everything looks ok.

Markus M


On Mon, Jun 7, 2010 at 12:33 PM, Hanlie Pretorius
<hanlie.pretorius at gmail.com> wrote:
> 2010/6/7, Hamish <hamish_b at yahoo.com>:
>> Hanlie Pretorius wrote:
>>> > I don't think it's this bug because this bug discards only one line of
>>> > data. I don't get any data in because the number of coordinate pairs
>>> > in the file is less than the number of cells in the defined region.
>> Markus Metz:
>>> Weird. In 6.4, r.in.xyz does import a file where the number of
>>> coordinate pairs is far less than the number of cells in the defined
>>> region. (I just did a simple test with two input lines and a region
>>> with 26.5 million cells, got clean import and correct result)
>>
>>
>> sorry, I'm not really grasping what the problem is. If you suspect
>> there is something weird going on can you make the .xyz.bz2 file
>> available for me to download, and supply the output of r.univar
>> `wc -l` and `r.in.xyz --verbose`?
>>
>>
>> Hamish
>>
> Ok, the text file (6.1MB compressed) that I use as input to r.in.xyz
> is available at:
> http://www.nedbib.za.net/dems/
>
> Output of r.in.xyz --verbose:
> -----
> Reading data ...
> Writing to map ...
> r.in.xyz complete. 0 points found in region.
> -----
>
> Output of r.univar:
> -----
> total null and non-null cells: 1146474
> total null cells: 1146474
>
> Of the non-null cells:
> ----------------------
> n: 0
> minimum: -nan
> maximum: -nan
> range: -nan
> mean: -nan
> mean of absolute values: -nan
> standard deviation: -nan
> variance: -nan
> variation coefficient: -nan %
> sum: 0
> -----
>
> output of wc -l:
> 1146370
>
> Output of r.info:
> -----
>  +----------------------------------------------------------------------------+
>  | Layer:    dem_2728ab_25m                 Date: Mon Jun  7 12:09:34 2010
>  | Mapset:   PERMANENT                      Login of Creator: hanlie
>  | Location: sa_tm_29deg_E
>  | DataBase: /media/0847147784/grassdata
>  | Title:    Raw x,y,z data binned into a raster grid by cell mean ( dem_2728
>  | Timestamp: none
>  |----------------------------------------------------------------------------
>  |
>  |   Type of Map:  raster               Number of Categories: 255
>  |   Data Type:    FCELL
>  |   Rows:         1011
>  |   Columns:      1134
>  |   Total Cells:  1146474
>  |        Projection: Transverse Mercator
>  |            N:   -49312.5    S:   -74587.5   Res:    25
>  |            E: -2987512.5    W: -3015862.5   Res:    25
>  |   Range of data:    min = -nan  max = -nan
>  |
>  |   Data Source:
>  |    /media/0847147784/data/CD-NGI/DEMS/25m dems/2728/ab/2728AB.ort.grass
>  |
>  |
>  |   Data Description:
>  |    generated by r.in.xyz
>  |
>  |   Comments:
>  |    r.in.xyz input="/media/0847147784/data/CD-NGI/DEMS/25m dems/2728/ab/\
>  |    2728AB.ort.grass" output="dem_2728ab_25m" method="mean" type="FCELL"\
>  |     x=1 y=2 z=3 zscale=1.0 percent=100
>  -----
>
> Thanks
> Hanlie
>