Dimension Scales in HDF-EOS2 & HDF-EOS5 Abe Taaheri, Raytheon IIS HDF & HDF-EOS Workshop XIV Champaign, IL Sep. 29, 2010 1 of #page

What is a Dimension Scale ? Dimension Scales & Metadata Dimension Scales APIs he2 he5 Code example Writing (he2, he5) Reading (he2, he5) Sample he2 and he5 files with Dimension Scales

What is a Dimension Scale? It is a sequence of numbers placed along a dimension to demarcate intervals along it HDF4 It is an array with size and name similar to its assigned dimension Stored using a structure similar to the SDS array One scale is assigned per dimension

* What is a Dimension Scale? HDF5 A HDF5 dataset. With additional metadata that identifies the dataset as a Dimension Scale Typically Dimension Scales are logically associated with the dimensions of HDF5 Datasets The meaning of the association is left to applications. * Pedro Vicente talk, HDF/ HDF-EOS Workshop IX 1 of #page

3 Dimension Scales Datasets Example: 3D dataset 3 Dimension Scales Datasets 5 Dataset: 3D Array with 5 x 7 x 10 dimensions 7 10 1 of #page

More on Dimension Scale in HDF5 A dimension scale is not required to be a 1-D array, or to have a specific datatype A dataset dimension can have more than 1 associated dimension scale A Dimension Scale can be shared by two or more Dataset dimensions 1 of #page

Example: 3D dataset in HDF5 Several Dimension Scales Datasets Dataset: 3D Array with 5 x 7 x 10 dimensions 1 of #page

HDF5 Dimension Scale Metadata When the Dimension Scale is associated with a dimension of a Dataset, the association is represented by attributes of the two datasets. The following dataset attributes are used to describe dimension scale datasets: Attribute named “CLASS” with the value “DIMENSION_SCALE” Optional attribute named “NAME” Attribute references to any associated Dataset 1 of #page

SDsetdimstrs(): label, unit, format SDgetdimstrs() HDF5 Since Version 4.0 ? SDsetdimscale() SDgetdimscale() SDsetdimstrs(): label, unit, format SDgetdimstrs() HDF5 Since Version 1.8 H5DSset_scale() H5DSattach_scale(), H5DSdetach_scale() H5DSset_label(), H5DSget_label() A few more APIs 1 of #page

HDF Augmentation Tool Augmentation Tool adds HDF5 Dimension Scales inside the file so that netCDF-4 APIs can access the data

Added a few routines to HDF-EOS2 to create dimension scales like HDF4 Version 2.17 Added a few routines to HDF-EOS5 to create dimension scales like those added by the HDF Augmentation Tool Version 1.13

HDF-EOS2 APIs

Name: SWsetdimscale Signature: intn SWsetdimscale( int32 swathID, char *fieldname, char *dimname, int32 dimsize, int32 numbertype, VOIDP data) Purpose: Sets dimension scale for a given dimension

Name: SWgetdimscale Signature: intn SWgetdimscale( int32 swathID, char *fieldname, char *dimname, int32 *dimsize, int32 *numbertype, VOIDP data) Purpose: Gets dimension scale for a given dimension

Name: SWsetdimstrs Signature: intn SWsetdimstrs( int32 swathID, char *fieldname, char *dimname, char *label, char *unit, char *format) Purpose: Sets the label, unit, and format strings for a given dimension

Name: SWgetdimstrs Signature: intn SWgetdimstrs( int32 swathID, char *fieldname, char *dimname, char *label, char *unit, char *format, intn len) Purpose: Gets the label, unit, and format strings for a given dimension

Similar APIs for Dimension Scales in Grid Fields

HDF-EOS5 APIs

Name: HE5_SWsetdimscale Signature: herr_t HE5_SWsetdimscale( hid_t swathID, char *fieldname, char *dimname, const hsize_t dimsize, hid_t numbertype, void * data) Purpose: Sets dimension scale for a field dimension within the swath

Name: HE5_SWgetdimscale Signature: long HE5_SWgetdimscale( hid_t swathID, char *fieldname, char *dimname, hsize_t *dimsize, hid_t *numbertype, void * data) Purpose: Gets dimension scale for a field dimension within the swath

Name: HE5_SWwritedscaleattr Signature: herr_t HE5_SWwritedscaleattr( hid_t swathID, const char *dimname, const char *attrname, hid_t ntype, hsize_t count[], void *datbuf) Purpose: Writes/Updates a dimension scale attribute in a specific swath

Name: HE5_SWreaddscaleattr Signature: herr_t HE5_SWreaddscaleattr( hid_t swathID, const char *dimname, const char *attrname, void *datbuf) Purpose: Reads a dimension scale attribute from a specific dimension

Name: HE5_SWinqdscaleattrs Signature: Long HE5_SWinqdscaleattrs( hid_t swathID, const char *dimname, char *attrnames, long *strbufsize) Purpose: Retrieve information about the attributes defined

Name: HE5_SWdscaleattrinfo Signature: herr_t HE5_SWdscaleattrinfo( hid_t swathID, const char *dimname, const char *attrname, hid_t *ntype, hsize_t *count) count : Number of attribute elements Purpose: Returns information about attribute(s) in a specific dimension scale

Similar APIs for Dimension Scales in Grid Zonal Average

Code Examples

Writing Code Example (HDF-EOS2) #include "hdf.h" #include "HdfEosDef.h" int main() { intn status, i; int32 swfid, SWid; int32 nbands, nGeoTrack; int32 bands[15]={3,6,9,12,15,18,23,26,29,32,33,34,36,37,39}; char label[16]; char unit[16]; char format[16]; float dataGeoTrack[20]; swfid = SWopen ( "SwathFile.hdf", DFACC_RDWR ); SWid = SWattach ( swfid, "Swath1“ );

for (i=0; i<20; i++) { dataGeoTrack[i] = (float) I; } nGeoTrack = 20; for (i=0; i<20; i++) { dataGeoTrack[i] = (float) I; } status = SWsetdimscale ( SWid, "Temperature", "GeoTrack", nGeoTrack, DFNT_FLOAT32, dataGeoTrack ); nbands = 15; status = SWsetdimscale ( SWid, "Spectra", "Bands", nbands, DFNT_INT32, bands ); strcpy (label, "Bands"); strcpy (unit, "none"); strcpy (format, "I2"); status = SWsetdimstrs ( SWid, "Spectra", "Bands", label, unit, format ); SWdetach ( SWid ); SWclose ( swfid ); return 0; }

Writing Code Example (HDF-EOS5) #include <HE5_HdfEosDef.h> int main() { herr_t status = FAIL; hid_t swfid = FAIL; hid_t SWid1 = FAIL; int data[15]={1,2,3,6,9,12,15,18,23,26,29,32, 33,34,35}; char label[16], unit[16], format[16]; int nbands; hsize_t count[3]; swfid = HE5_SWopen ( "Swath.h5", H5F_ACC_RDWR ); SWid1 = HE5_SWattach ( swfid, "Swath1“ );

nbands = 15; status = HE5_SWsetdimscale ( SWid1, "Spectra", "Bands", nbands, H5T_NATIVE_INT, (void *)data ); strcpy(label, "Bands Dim"); strcpy(unit, "None"); strcpy(format, "I2"); count[0]= 12; status = HE5_SWwritedscaleattr ( SWid1, "Bands", "label", H5T_NATIVE_CHAR, count, label ); count[0]= 6; status = HE5_SWwritedscaleattr ( SWid1, "Bands", "unit", H5T_NATIVE_CHAR, count, unit ); count[0]= 4; status = HE5_SWwritedscaleattr ( SWid1, "Bands", "format", H5T_NATIVE_CHAR, count, format );

int datbuf_i1[1] = {-999}; count[0]= 1; status = HE5_SWwritedscaleattr ( SWid1, "Bands", "MissingValue", H5T_NATIVE_INT, count, datbuf_i1 ); int datbuf_i2[3] = {-999, 0, 999}; count[0]= 3; status = HE5_SWwritedscaleattr(SWid1, "Bands", "IntValues", H5T_NATIVE_INT, count, datbuf_i2 ); HE5_SWdetach ( SWid1 ); HE5_SWclose ( swfid ); return 0; }

Reading Code Example (HDF-EOS2) #include "hdf.h" #include "HdfEosDef.h" Int main() { intn status, i; int32 swfid, SWid; int32 *datbuf_int32; int32 nbands, data_type, dimsize, dimsize1; intn len, buffsize; char label[16], unit[16], format[16]; swfid = SWopen ( "SwathFile.hdf", DFACC_RDWR ); SWid = SWattach ( swfid, "Swath1“ ); /* get Bands */ dimsize = SWdiminfo ( SWid, "Bands“ ); buffsize = SWgetdimscale ( SWid, "Spectra", "Bands", &dimsize1, &data_type, NULL );

datbuf_int32 = (int32 *) malloc(buffsize); buffsize = SWgetdimscale ( SWid, "Spectra", "Bands", &dimsize1, &data_type, (void *)datbuf_int32 ); for (i=0; i<dimsize; i++) { printf("i = %d datbuf_int32 = %d\n", i, datbuf_int32[i]); } /* get str attributes of Bands*/ len = 15; status = SWgetdimstrs ( SWid, "Spectra", "Bands", label, unit, format, len ); printf(" \t\tlabel = %s unit = %s format = %s \n\n", label, unit, format); free(datbuf_int32); datbuf_int32 = NULL; SWdetach ( SWid ); SWclose ( swfid ); return 0; }

Reading Code Example (HDF-EOS5) #include <HE5_HdfEosDef.h> int main() { herr_t status = FAIL; hid_t swfid = FAIL, SWid = FAIL, numtype; int i,j, bufsize; int *databuff; long nattr, strbufsize; char *attrlist, *attrname = (char *)NULL; size_t fldnmlen[HE5_HDFE_NAMBUFSIZE]; char *fldnm[HE5_HDFE_NAMBUFSIZE]; hid_t *ntype; hsize_t count = 0; void *attr; int *attr_int; float *attr_flt; char *attr_char; hsize_t dimsize; swfid = HE5_SWopen ( "Swath.h5", H5F_ACC_RDWR ); SWid = HE5_SWattach ( swfid, "Swath1“ );

bufsize = HE5_SWgetdimscale ( SWid, "Spectra", "Bands", &dimsize, bufsize = HE5_SWgetdimscale ( SWid, "Spectra", "Bands", &dimsize, &numtype, NULL ); databuff = (int *) malloc(bufsize ); bufsize = HE5_SWgetdimscale ( SWid, "Spectra", "Bands", &dimsize, &numtype, (void *)databuff ); for( i = 0; i < dimsize; i++) { printf ("DscaleVal[%d] = %d\n",i,databuff[i] ); } nattr = HE5_SWinqdscaleattrs ( SWid, "Bands", NULL, &strbufsize ); attrlist = (char *) calloc(strbufsize + 1, sizeof(char)); nattr = HE5_SWinqdscaleattrs ( SWid, "Bands", attrlist, &strbufsize ); nattr = HE5_EHparsestr(attrlist, ',', fldnm, fldnmlen);

for( i = 0; i < nattr; i++) { attrname = (char *) calloc(fldnmlen[i] + 1, sizeof(char) ); memmove ( attrname,fldnm[i],fldnmlen[i] ); ntype = (hid_t *) calloc(1, sizeof(hid_t)); if ( strcmp ( attrname, "REFERENCE_LIST") == 0 ) continue; status = HE5_SWdscaleattrinfo ( SWid,"Bands", attrname, ntype, &count ); if( (int)*ntype == 0) { attr_int = (int *) malloc(count*sizeof(int)); attr = (void *) attr_int; } if( (int)*ntype == 10) { attr_flt = (float *) malloc(count*sizeof(float)); attr = (void *) attr_flt; } if( (int)*ntype == 57) { attr_char = (char *) malloc((count+1)*sizeof(char)); attr = (void *) attr_char; } status = HE5_SWreaddscaleattr ( SWid,"Bands", attrname, attr ); printf("\tAttribute Name: %s \n",attrname); printf("\tNumber of attr elem: %lu \n", (unsigned long)count); printf("\tData type of attribute: %d \n", (int)*ntype);

if( (int)*ntype == 0) { attr_int = (int *) attr; for (j = 0; j < count; j++) { printf("\tAttrvalue[%d]: %d \n", j,attr_int[j]); } } if( (int)*ntype == 10) { attr_flt = (float *) attr; for (j = 0; j < count; j++) { printf("\tAttrvalue[%d]: %f \n", j,attr_flt[j]); } if( (int)*ntype == 57) { attr_char = (char *) attr; attr_char[count]='\0'; printf("\tAttrvalue: %s \n", attr_char); free ( attr_char ); HE5_SWdetach ( SWid ); HE5_SWclose ( swfid ); return 0;

Test File content (he2) HDFView 2.4: uses plug-in with hdf-eos5-1.11, Hdfeos2.15, HDF4.2r3, HDF5-1.6.7

Test File content (he5) HDFView 2.4: uses plug-in with hdf-eos5-1.11, Hdfeos2.15, HDF4.2r3, HDF5-1.6.7

Test File content (he5) HDFView 2.6: Without plug-in HDF4.2r4, HDF5-1.8.3

Test File content (he5) HDFView 2.6: uses plug-in with hdf-eos5-1.12, Hdfeos2.16, HDF4.2r4, HDF5-1.8.3

File content (HIRDLS he5) HIRDLS he5 Modified with HDF Augmentation Tool

Suggestions? Do we need new APIs ? Improvements for existing APIs ? What else?

Thank You!