Re: GMT 5 default format

Just wanted let you know, that I modified
MagPick to read GMT HDF format.

Mikhail

On 2/6/2014 6:31 AM, Lester Anderson wrote:
> Thanks for the information
> Cheers
> Lester
>
> > Date: Thu, 6 Feb 2014 11:52:21 +0000
> > From: [email protected]
> > Subject: Re: [GMT-HELP] GMT 5 default format
> > To: [email protected]
> >
> > Hi Remko and all
> >
> > That is all correct but I want also warn you guys about this GDAL
> > bug/limitation
> >
> > http://trac.osgeo.org/gdal/ticket/5291
> >
> > that will pop up (hidden) for instance to QGIS users
> >
> > Joaquim
> >
> > > Dear Lester,
> > >
> > > One option is to use
> > > gmt set IO_NC4_CHUNK_SIZE classic
> > >
> > > But I also want to urge you to either update the tools you use, or 
> if no update is available to urge the makers of those tools to finally 
> update to link against the netCDF 4 library.
> > >
> > > NetCDF 4 was introduced already some FIVE years ago and is now at 
> version 4.3.1.1. To hold off on the very useful functionalities of the 
> netCDF 4 library (particularly internal compression) would be like 
> trying to move the clock many years back.
> > >
> > > Remko
> > >
> > > On 6 Feb 2014, at 08:04, Lester 
> Anderson<[email protected]> wrote:
> > >
> > >> Hello,
> > >>
> > >> I have spotted a slight difference in the default grid formats 
> from v4 to v5 and this appears to give some issues loading into other 
> applications:
> > >>
> > >> VERSION 5
> > >> black1_emag2b_RTP.grd: Title: Anomaly reducted to the pole
> > >> black1_emag2b_RTP.grd: Command: grdredpol black1_emag2a.grd 
> -Gblack1_emag2b.grd -T2013 -W1 -F45/45 -V
> > >> black1_emag2b_RTP.grd: Remark:
> > >> black1_emag2b_RTP.grd: Gridline node registration used 
> [Geographic grid]
> > >> black1_emag2b_RTP.grd: Grid file format: nf = GMT netCDF format 
> (32-bit float),COARDS, CF-1.5
> > >> black1_emag2b_RTP.grd: x_min: 20 x_max: 50 x_inc: 0.0333333333333 
> name: longitude [degrees_east] nx: 901
> > >> black1_emag2b_RTP.grd: y_min: 35 y_max: 50 y_inc: 0.0333333333333 
> name: latitude [degrees_north] ny: 451
> > >> black1_emag2b_RTP.grd: z_min: -1385.10412598 z_max: 3309.81860352 
> name: nT
> > >> black1_emag2b_RTP.grd: scale_factor: 1 add_offset: 0
> > >> black1_emag2b_RTP.grd: format: netCDF-4 chunk_size: 129,151 
> shuffle: on deflation_level: 3<------
> > >>
> > >> VERSION 4
> > >> black1_emag2b_RTP_v2.grd: Title: Grid computed inside Mirone
> > >> black1_emag2b_RTP_v2.grd: Command:
> > >> black1_emag2b_RTP_v2.grd: Remark: File written from Matlab
> > >> black1_emag2b_RTP_v2.grd: Gridline node registration used 
> [Geographic grid]
> > >> black1_emag2b_RTP_v2.grd: Grid file format: nf = GMT netCDF 
> format (32-bit float), COARDS, CF-1.5
> > >> black1_emag2b_RTP_v2.grd: x_min: 20 x_max: 50 x_inc: 
> 0.0333333333333 name: longitude [degrees_east] nx: 901
> > >> black1_emag2b_RTP_v2.grd: y_min: 35 y_max: 50 y_inc: 
> 0.0333333333333 name: latitude [degrees_north] ny: 451
> > >> black1_emag2b_RTP_v2.grd: z_min: -1385.10412598 z_max: 
> 3309.81860352 name: z [unknown]
> > >> black1_emag2b_RTP_v2.grd: scale_factor: 1 add_offset: 0
> > >> black1_emag2b_RTP_v2.grd: format: classic<------
> > >>
> > >> The format reference from the headers are different. With version 
> 4 there are no issues loading GMT (netCDF) grids into other 
> applications like MagPick or QGIS (1.8 to 2.1), but with version 5 
> they are considered an unknown format, yet still the default format (=nf).
> > >>
> > >> From gmtdefaults:
> > >>
> > >> # I/O Parameters
> > >> #
> > >> IO_COL_SEPARATOR = tab
> > >> IO_GRIDFILE_FORMAT = nf
> > >> IO_GRIDFILE_SHORTHAND = false
> > >> IO_HEADER = false
> > >> IO_N_HEADER_RECS = 0
> > >> IO_NAN_RECORDS = pass
> > >> IO_NC4_CHUNK_SIZE = auto
> > >> IO_NC4_DEFLATION_LEVEL = 3
> > >> IO_LONLAT_TOGGLE = false
> > >> IO_SEGMENT_MARKER =>
> > >> #
> > >>
> > >> Should any parameters above be tweaked?
> > >>
> > >> It is not a big issue as it is easy to change to a format that 
> works in other applications, but it is worth noting that the subtle 
> change in the format seems to have a big impact, given that everything 
> else is identical. In terms of formats, what constitutes the "classic" 
> format in the list under grdreformat?
> > >>
> > >> Cheers
> > >> Lester
> > >> To unsubscribe, send the message "signoff gmt-help" to 
> [email protected]
> > > To unsubscribe, send the message "signoff gmt-help" to 
> [email protected]
> > >
> > >
> >
> > To unsubscribe, send the message "signoff gmt-help" to 
> [email protected]
> To unsubscribe, send the message "signoff gmt-help" to 
> [email protected] 




PLEASE NOTE: This message, including any attachments, may include privileged,
confidential and/or inside information. Any dissemination, distribution or copy
of this communication by   anyone other than the intended recipient is strictly
prohibited. If you are not the intended recipient, please notify the sender by
replying to this message and then delete it from your system. Information
provided via electronic media is not guaranteed against defects including
translation and transmission errors. The company accepts no liability for any
damage caused by any virus transmitted by this email.

Geometrics Inc. | 2190 Fortune Drive | San Jose, CA 95131 USA

To unsubscribe, send the message "signoff gmt-help" to [email protected]