Re: ncl_convert2nc: filetype 'dat' not supported.

Reading binary can be a hassle because several factors
need be explicitly know.

The data provider (eg, whoever created the original file)
should state if the file was generated on a 'big-endian' or
'little-endian' machine. Further, was the data written as
a flat binary file or via a fortran sequential write
statement. If the latter is true, the fortran embeds
'hidden' record separators that result in the file
being slightly larger than is expected.

===
ncl 0> nlat = 37
ncl 1> klev = 23
ncl 2> ntim = 16314
ncl 3> bytes = ntim*klev*nlat*4 ; 4 is 4 bytes per float
ncl 4> print(bytes)

Variable: bytes
[snip]
Coordinates:
(0) 55532856

This matches the size of your file:

55532856 Jun 24 14:48 ERA40Tzm.dat

Hence, it is a flat binary file. This means either
fbindirread or cbinread can be used to read the file.

==============================================
Next, what endian are associated with the binary values?

Try:
ncl 5> x = fbindirread("ERA40Tzm.dat", 0, (/16314,23,37/) )
ncl 6> print(x)

If the numbers look good ... then you have
successfully read the binary file.

Note it could also be: (/16314,37,23/) but this is less common.
=================================================

If the numbers do not look realistic, it likely means the file
was created on a different system than you are using.

EG: if you are on a big-endian system then use
setfile option to tell NCL to switch the bytes:

setfileoption("bin","ReadByteOrder","LittleEndian")

Please red:
http://www.ncl.ucar.edu/Document/Functions/Built-in/setfileoption.shtml

Good luck

On 06/24/2013 02:45 PM, Erika Folova wrote:
> I forgot to mention that
> the timestep of the data is daily from 1958 to 2002.
> in total ntime = 16314
>
> I look forward to your response,
>
> -- Erika
>
>
>
>
> On Tue, Jun 25, 2013 at 5:42 AM, Erika Folova <e.folova@gmail.com
> <mailto:e.folova@gmail.com>> wrote:
>
> Hi Everyone,
>
> I need a bit help,
> I have a binary data *.dat with dimendsions (lat, level, time),
>
> nlat =37
> nlevel=23
> ntime= 16314
>
> the latitude extending from equator (0) to 90oN (only northern
> hemisphere).
> I have been strugling to convert this *binary file to *nc*,
> but was still failed,, I really appreciate if anyone willing to help
> me for this case,
> I put the data in ftp cd incoming by name:
>
> *ERA40Tzm.dat*
> *
> *
> Thank you so much,
> -- Erika,
>
>
>
>
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Received on Mon Jun 24 15:11:51 2013