[GRASS-user] Projection information

[stephen sefick]

Hamish,

Thank you very much.  I set the zone to 17 which is the right utm zone
for "ftbr".  All of the input data has been in or transformed to the
right projection I guess I just didn't set this up correctly when I
created the projection location.  Thanks so much for all of your help.
kindest regards,

Stephen Sefick

On Wed, Sep 22, 2010 at 11:09 PM, Hamish <hamish_b at yahoo.com> wrote:
> stephen sefick wrote:
>> These are three different projection
>> locations that I have set up over
>> the past year with ever changing GRASSes.  tcl/tk
>> interface up to the
>> new GRASS6.4.1svn.  I have consistently kept
>> everything in the correct
>> projections for input data.
>>
>> ftbn: utm nad83 grs80 zone 17
>> srs: utm nad83 grs80 zone 17
>> ftbn: utm nad83 grs80 zone 17
>>
>>
>> should I be worried that the ProjInfo files for the three
>> below differ slightly?  Can I safely make them all look the
>> same?  Does this matter?  Thanks in advance for all of the help.
>>
>>
>> ftbr:
>> name: Universal Transverse Mercator
>> datum: nad83
>> towgs84: 0.000,0.000,0.000
>> proj: utm
>> ellps: grs80
>> a: 6378137.0000000000
>> es: 0.0066943800
>> f: 298.2572221010
>
> a, es, and f are just grs80 expanded, try `proj -le` from the command line.
> +towgs84=0,0,0 pretty much means "don't do anything to get to wgs84"
>
> I see that proj=utm but the zone= is missing. If so, the projection
> definition is incomplete.
>
>
>> srs:
>> name: Universal Transverse Mercator
>> proj: utm
>> datum: nad83
>> ellps: grs80
>> zone: 17
>> no_defs: defined
>
> equivalent, see http://trac.osgeo.org/proj/wiki/GenParms for details.
>
>> ftbn:
>> name: UTM
>> datum: nad83
>> towgs84: 0.000,0.000,0.000
>> proj: utm
>> ellps: grs80
>> a: 6378137.0000000000
>> es: 0.0066943800
>> f: 298.2572221010
>> zone: 16
>
> note the above says zone 16, not 17. otherwise equivalent.
>
>
> Hamish
>
>
>
>
>



-- 
Stephen Sefick
____________________________________
| Auburn University                                   |
| Department of Biological Sciences           |
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