error in read_srtm30plus.m script ....

[mashinde]

Dear Friends ,

I am building a grid with seagrid. I have following errors while reading bathymetry via read_srtm30plus.m script,

[xbathy,ybathy,zbathy]=read_srtm30plus([-20 37],[30 49],60);
??? Error using ==> rtifc
/tmp/tp8377d624_0366_4942_b7c9_623a47471fcf: Not a TIFF file, bad magic number 16188 (0x3f3c).

Error in ==> readtif at 52
[X, map, details] = rtifc(args);

Error in ==> imread at 432
[X, map] = feval(fmt_s.read, filename, extraArgs{:});

Error in ==> read_srtm30plus at 60
pix=imread(url,'tif');


So, can you please tell how to solve this error.


in addition also look the discussion page link :

https://www.myroms.org/wiki/index.php/Talk:seagrid




Thanks

[gmaze]

Hi, I was wondering if you have found a resolution to this problem?

[rsignell]

Unfortunately NASA took down the WMS site, but fortunately, it's easy to get
subsetted global and other bathymetry data using NCTOOLBOX:

1. Get NCTOOLBOX for Matlab (easy install at http://code.google.com/p/nctoolbox/)

2. Use the "geosubset" method to subset bathy data. For SRTM30PLUS, it would look like:

Code: Select all

url='http://geoport.whoi.edu/thredds/dodsC/bathy/srtm30plus_v1.nc';
nc=ncgeodataset(url)
topovar=nc.geovariable('topo')
s.lon=[-71.2 -69.9]
s.lat=[41 42];
%s.h_stride=[2 2];  %get every other value
g=topovar.geosubset(s)
imagesc(g.grid.lon,g.grid.lat,g.data);axis xy;colorbar;
title('SRTM (m)')

You can substitute any other OPeNDAP URL in this catalog, which includes ETOPO2, ETOPO1, NOAA Coastal Relief Model for the US, and more:
http://geoport.whoi.edu/thredds/bathy_catalog.html

Good Luck,
Rich

[AlexisEspinosa]

Dear Prof. Signell,

Thanks a lot for all your shared tools!

It would be nice if someone can update the wikiRoms page. Both, the svn repositories and the usage of read_srtm30plus are incorrect and mislead us.

Thanks a lot,
Alexis Espinosa
UWA

[pilipalapipa]

Dear friends,

I tried the method below, but I got the wrong message like this,
-----------------------------------------
>> [x,y,z]=read_srtm30plus(ax(1:2),ax(3:4),30);
Warning: The netcdf-java cdm contains no coordinate information
associated with the variable. Returning ncvariable instead of
ncgeovariable object. (Methods that rely on coordinate information
like 'grid' or 'geosubset' are not available.
> In ncgeodataset>ncgeodataset.geovariable at 215
In ncgeodataset>ncgeodataset.subsref at 378
In read_srtm30plus2 at 32
??? Error using ==> subsref
No appropriate method, property, or field geosubset for class
ncvariable.

Error in ==> ncvariable>ncvariable.subsref at 295
sref = builtin('subsref',obj,s);

Error in ==> read_srtm30plus2 at 36
g=topovar.geosubset(s);

------------------------------
I will be pretty appreciated if anyone gives some suggestions,

Tony

Unfortunately NASA took down the WMS site, but fortunately, it's easy to get
subsetted global and other bathymetry data using NCTOOLBOX:

1. Get NCTOOLBOX for Matlab (easy install at http://code.google.com/p/nctoolbox/)

2. Use the "geosubset" method to subset bathy data. For SRTM30PLUS, it would look like:

Code: Select all

url='http://geoport.whoi.edu/thredds/dodsC/bathy/srtm30plus_v1.nc';
nc=ncgeodataset(url)
topovar=nc.geovariable('topo')
s.lon=[-71.2 -69.9]
s.lat=[41 42];
%s.h_stride=[2 2];  %get every other value
g=topovar.geosubset(s)
imagesc(g.grid.lon,g.grid.lat,g.data);axis xy;colorbar;
title('SRTM (m)')

You can substitute any other OPeNDAP URL in this catalog, which includes ETOPO2, ETOPO1, NOAA Coastal Relief Model for the US, and more:
http://geoport.whoi.edu/thredds/bathy_catalog.html

Good Luck,
Rich

[Caffery]

I also meet that problem like you. But my problem is lack of 'private'. i don't know whether it needs to download and where.

Code: Select all

>> [xbathy,ybathy,zbathy]=read_srtm30plus(lon_range,lat_range,60);
??? Error: File: ncgeodataset.m Line: 60 Column: 38
Undefined function or variable 'private'.

Error in ==> read_srtm30plus at 34
nc=ncgeodataset(url);

>> 

thnks and i hope that i can get answers.