hdiff examples

These examples use the files hdifftst1.hdf and hdifftst2.hdf. 

The table in hdiff_hdp.html shows the hdp output of the sds and vdata in the files.

Example: 1.0
Command: hdiff -g hdifftst1.hdf hdifftst2.hdf
Notes:  Compare global attributes only
Output: 

$hdiff -g hdifftst1.hdf hdifftst2.hdf

*****     Global attributes comparison:     *****

---------------------------
Attr Name: File_contents
< "Storm_track_data1"
> "Storm_track_data2"

Example: 1.1
Command: hdiff -s hdifftst1.hdf hdifftst2.hdf
Notes:  Compare SD local attributes only
Output: 

$hdiff -s hdifftst1.hdf hdifftst2.hdf

*****     SD attributes comparison:     *****

---------------------------
SD Name: dset1
<<<<
Dimension: (3, 2) ;
	dset1:Valid_range = 1.f, 1.f ;
>>>>
Dimension: (3, 2) ;
	dset1:Valid_range = 1.f, 2.f ;

Example: 1.2
Command: hdiff -d hdifftst1.hdf hdifftst2.hdf
Notes:  Compare SD data only
Output: 

$hdiff -d hdifftst1.hdf hdifftst2.hdf

*****     SD Data comparison:     *****

---------------------------
SD Name: dset1 .... Comparing
Index: 1,   File1: 1,   File2: 2
Index: 2,   File1: 1,   File2: 3
Index: 3,   File1: 1,   File2: 4

---------------------------
SD Name: dset2 .... Comparing
Index: 1,   File1: 1,   File2: 2
Index: 2,   File1: 1,   File2: 3
Index: 3,   File1: 1,   File2: 4

Example: 1.3
Command: hdiff -D hdifftst1.hdf hdifftst2.hdf
Notes:  Compare Vdata data only
Output: 

$hdiff -D hdifftst1.hdf hdifftst2.hdf

*****     Vdata comparison:     *****

*****     Vdata comparison:     *****

Comparing... vdata1

---------------------------
Vdata Name: vdata1 (Data record comparison)
> 0: V
< 0: X

Comparing... vdata2

---------------------------
Vdata Name: vdata2 (Data record comparison)
> 0: 1 2 3 4 
< 0: 1 1 1 1 

Comparing... vdata3

---------------------------
Vdata Name: vdata3 (Data record comparison)
> 0: 1.000000 2.000000 3.000000 4.000000 5.000000 6.000000 
< 0: 1.000000 1.000000 1.000000 1.000000 1.000000 1.000000 

Example: 1.4
Command: $hdiff -d -S hdifftst1.hdf hdifftst2.hdf
Notes:  Print statistics
Output: 

$hdiff -d -S hdifftst1.hdf hdifftst2.hdf

*****     SD Data comparison:     *****

---------------------------
SD Name: dset1 .... Comparing
Index: 1,   File1: 1,   File2: 2
Index: 2,   File1: 1,   File2: 3
Index: 3,   File1: 1,   File2: 4
Type: Integer4  Npts: 6  Ndiff: 3 (50.000000%)
Avg Diff: 1.000000e+00   Max. Diff: 3
Range File1: 1/6  File2: 1/6
Regression  N: 6  Slope: 6.727273e-01  Intercept: 1.818182e+00  R: 8.433083e-01

---------------------------
SD Name: dset2 .... Comparing
Index: 1,   File1: 1,   File2: 2
Index: 2,   File1: 1,   File2: 3
Index: 3,   File1: 1,   File2: 4
Type: Integer4  Npts: 6  Ndiff: 3 (50.000000%)
Avg Diff: 1.000000e+00   Max. Diff: 3
Range File1: 1/6  File2: 1/6
Regression  N: 6  Slope: 6.727273e-01  Intercept: 1.818182e+00  R: 8.433083e-01

Example: 1.5
Command: hdiff -d -v dset1 hdifftst1.hdf hdifftst2.hdf
Notes:  Compare SD data on variable(s) <var1>,... only
Output: 

$hdiff -d -v dset1 hdifftst1.hdf hdifftst2.hdf

*****     SD Data comparison:     *****

---------------------------
SD Name: dset1 .... Comparing
Index: 1,   File1: 1,   File2: 2
Index: 2,   File1: 1,   File2: 3
Index: 3,   File1: 1,   File2: 4

Example: 1.6
Command: hdiff -D -u vdata1 hdifftst1.hdf hdifftst2.hdf
Notes:  Compare vdata on variable(s) <var1>,... only
Output: 

$hdiff -D -u vdata1 hdifftst1.hdf hdifftst2.hdf

*****     Vdata comparison:     *****

*****     Vdata comparison:     *****

Comparing... vdata1

---------------------------
Vdata Name: vdata1 (Data record comparison)
> 0: V
< 0: X

Example: 1.7
Command: hdiff -d -e 2 hdifftst1.hdf hdifftst2.hdf
Notes:  Print difference up to count number for each variable
Output: 

$hdiff -d -e 2 hdifftst1.hdf hdifftst2.hdf

*****     SD Data comparison:     *****

---------------------------
SD Name: dset1 .... Comparing
Index: 1,   File1: 1,   File2: 2
Index: 2,   File1: 1,   File2: 3

---------------------------
SD Name: dset2 .... Comparing
Index: 1,   File1: 1,   File2: 2
Index: 2,   File1: 1,   File2: 3

Example: 1.8
Command: hdiff -d -t 2 hdifftst1.hdf hdifftst2.hdf
Notes:  Print difference when it is greater than limit
Output: 

$hdiff -d -t 2 hdifftst1.hdf hdifftst2.hdf

*****     SD Data comparison:     *****

---------------------------
SD Name: dset1 .... Comparing
Index: 3,   File1: 1,   File2: 4

---------------------------
SD Name: dset2 .... Comparing
Index: 3,   File1: 1,   File2: 4