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[netCDFJava #NMT-724530]: vlen_t big_endian problem

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  • Subject: [netCDFJava #NMT-724530]: vlen_t big_endian problem
  • Date: Mon, 03 Jan 2011 13:55:05 -0700
Hi Bruno:

I should have a release fixing this in the next few days. thanks for reporting.

> Hi John,
> For file test3_p1_d1wave.nc (In Big Endian) this works correctly, but for
> file fpscminicodac_1.nc (in Little Endian) the API modifications produce the
> previous error (reported in last e-mail but now for little-endian files)...
> In this API version vlen_t values are always read in Big Endian and in last
> version they were read in Little Endian... The modifications inverted the
> error and does not detect the order of endian in the file.
> Thanks for your support,
> Regards,
> 
> Bruno Santos
> 
> 
> 2010/12/23 Unidata netCDF Java Support <address@hidden
> >
> 
> > Hi Bruno:
> >
> > Ive reissued the release version 4.2.18.20101223.2214, available at
> >
> > http://www.unidata.ucar.edu/software/netcdf-java/
> >
> > with this bug fixed. thanks for reporting the problem.
> >
> > John
> >
> > > Hello,
> > >
> > > I've problem when read vlen_t data stored in big endian format. In
> > attached
> > > file all variable are read correctly except  the variable levels from
> > type
> > > vlen_t. For example, for value 549 the value read by as.getInt(i) is
> > > 620888064, in Hexadecimal 549 is 00 00 02 25 and 620888064 is 25 02 00
> > 00...
> > > I correct this manually, but can you update the java API?
> > > Best Wishes,
> > >
> > > Bruno Santos
> > >
> > >
> > > Here the code:
> > > *Array data = dataLevels.read(initialIndex + ":" + finalIndex +
> > > ",:");*
> > > // loop over outer dimension
> > > int x = 0;
> > > long samplesTotal = 0;
> > > long maxSamples = 200000L;
> > >
> > > *while (data.hasNext() && samplesTotal < maxSamples) {*
> > > Array as = (Array) data.next(); // inner variable length array
> > > of short
> > > //ArrayInt.D1 as = (ArrayInt.D1) data.next(); // inner variable
> > > length array of short
> > > long nextTime = 0;
> > > long timeSlice = 0;
> > >
> > > //System.out.println("Data: " + data.next().getClass());
> > > if (sPeriodArray.get(x) > 0) {
> > > timeSlice = sPeriodArray.get(x);
> > > } else {
> > > //----------Change
> > > long samplesPerSecond = sRateArray.get(x);
> > > timeSlice = 1000000000 / samplesPerSecond;
> > > }
> > >
> > > //System.out.println("as.getSize: " + as.getSizeBytes());
> > > //System.out.println("as.getSize: " + as.getSize());
> > > int i = 0;
> > > while (i < as.getSize()){
> > > *//Incorrect value*
> > > int aux = as.getInt(i);
> > >
> > > *                if (bigEndian){*
> > > *                    int aux1;*
> > > *                    int aux2;*
> > > *                    int aux3;*
> > > *                    int aux4;*
> > > *
> > > *
> > > *                    aux1 = (aux & 0xFF) << 24;*
> > > *                    aux2 = (aux & 0xFF00) << 8;*
> > > *                    aux3 = (aux & 0xFF0000) >> 8;*
> > > *                    aux4 = (aux & 0xFF000000) >> 24;*
> > > *
> > > *
> > > *                   //Corrected value*
> > > *                    aux = (aux1 & 0xFF000000) | (aux2 & 0x00FF0000)|
> > (aux3
> > > & 0x0000FF00) | (aux4 & 0x000000FF);*
> > > }
> > > }
> > >
> > >
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: NMT-724530
> > Department: Support netCDF Java
> > Priority: Normal
> > Status: Closed
> >
> >
> 
> 


Ticket Details
===================
Ticket ID: NMT-724530
Department: Support netCDF Java
Priority: High
Status: Closed