[ncl-talk] How to convert a contour map to a raster file from a nc file?

[zoe jacobs]

Dear Dave,
I meant that I have a nc file which is an output of a model. I can plot a
contour map from that file through a remote server. I have both the model
and NCL on a remote server. However, once I copy that nc file from remote
server to my desktop Panoply cannot read that nc file.
I hope it is clear now.
Best wishes,

On Wed, Jun 10, 2020 at 10:32 PM Dave Allured - NOAA Affiliate <
dave.allured at noaa.gov> wrote:

> This is a bit confusing.  Are you saying you can run NCL on your remote
> server, and make some kind of smaller file that you can then download?  Or
> are you running NCL locally and reading this Netcdf file through a server
> path or a URL?
>
>
> On Wed, Jun 10, 2020 at 10:45 AM zoe jacobs <zoejacobs1990 at gmail.com>
> wrote:
>
>> Dear Dave,
>> Many thanks for your explanations. My problem is that my nc file is just
>> known by the remote server I work at. After copying the file to my desktop,
>> and opening it by Panoply , it is no longer valid as a nc file ! . So I
>> look for a way to sort it out. What can I do please?
>> Many thanks in advance,
>> Best wishes,
>>
>> On Tue, Jun 9, 2020 at 10:19 PM Dave Allured - NOAA Affiliate <
>> dave.allured at noaa.gov> wrote:
>>
>>> According to this article, your original Netcdf file is already in a GIS
>>> raster format.
>>>
>>>     https://en.wikipedia.org/wiki/GIS_file_formats
>>>
>>> You should be able to skip the plotting step, and use the Netcdf file
>>> directly in ArcGIS.  Minor adjustments may be needed for coordinates and
>>> area subsetting.  My guess is that this is really what you want to do.
>>>
>>> The expression "raster format" is problematical because it is used for
>>> at least three fundamentally different things in computer graphics.
>>> Generically, this refers to common "bit-mapped" image file formats such as
>>> png, gif, and jpeg.  In GIS and satellite imagery, it refers to a variety
>>> of gridded data formats, including Netcdf.  And NCL has a specialized
>>> usage, referring to the rendering of gridded data as visibly rectangular
>>> blocks when making plots, rather than smooth or segmented outlines.  It
>>> would be nice if these nuances of terminology were discussed in NCL
>>> documentation, but, um, they are not.
>>>
>>> To make things more confusing, some of these formats can be "rendered"
>>> in one of the other formats, often losing software compatibility in the
>>> process.  The picture on your example raster_4.ncl is a perfect example of
>>> this.  That is an NCL "raster plot" projected onto a PNG "raster format"
>>> image file for website display.  The "pixels" before and after are
>>> completely different.  So be careful about which usage you are discussing.
>>>
>>>
>>> On Tue, Jun 9, 2020 at 10:06 AM zoe jacobs via ncl-talk <
>>> ncl-talk at mailman.ucar.edu> wrote:
>>>
>>>> Dear all NCL users,
>>>>
>>>> I would like to create a map plot in raster format from a nc file . So
>>>> I can then use it on ArcGIS. Please have a look at the following link
>>>> https://www.ncl.ucar.edu/Applications/raster.shtml , example
>>>> easter_4.ncl . I already could plot a contour map from my nc file, and
>>>> I just wonder which command should I add to my script to convert my plot to
>>>> be in a raster format?
>>>> Would you please kindly advise me in this regard?
>>>> Best wishes,
>>>>
>>>
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