[gradsusr] Problem in opening MODIS HDF files
James T. Potemra
jimp at hawaii.edu
Sat Oct 13 22:46:36 EDT 2012
Ehsan:
I think there is a character limit on the variable name. So, you have
a variable called "Angstrom_Exponent_Land_QA_Mean", but GrADS
is looking for "angstrom_expone". Instead, you can map the variable
to something shorter (see http://www.iges.org/grads/gadoc/gadocindex.html),
e.g., in your ctl file:
Angstrom_Exponent_Land_QA_Mean=>AELQA_Mean 0 1, 1, 0, 0
Surface pressure [hPa]
then open and display "aelqa_mean", or whatever you call it.
Jim
On 10/13/12 1:54 PM, Ehsan Erfani wrote:
> Hi again,
>
> I attached an hdf file with a ctl (I downloaded the data from Giovanni
> website and I wrote the ctl). This time, the Grads can open the data,
> but when I write the command: d Angstrom_Exponent_Land_QA_Mean, This
> error message appears:
> Syntax Error: Invalid Operand
> 'angstrom_exponent' not a variable or function name
> Error ocurred at column 1
> DISPLAY error: Invalid expression
> Expression = angstrom_exponent_land_qa_mean
>
> But, I am sure the name of variable is true. I checked it by HDFView
> and this is the information from HDFView:
> Angstrom_Exponent_Land_QA_Mean (720, 2)
> 32-bit floating-point, 180 x 360
> Number of attributes = 18
> _FillValue = -9999.0
> QA_Useful_Flag_Bit = 0
> Quality_Assurance_Data_Set = Quality_Assurance_Land
> scale_factor = 1.0
> QA_Value_Start_Bit = 1
> add_offset = 0.0
> long_name = Angstrom exponent (Land) for 0.47 and 0.66
> microns: Level-2 QA Weighted Mean
> Statistic_Type = Simple
> units = unitless
> QA_Byte = 0
> Aggregation_Data_Set = None
> valid_range = -500,5000
> Included_Level_2_Nighttime_Data = False
> Derived_From_Level_2_Data_Set = Angstrom_Exponent_Land
> QA_Value_Num_Bits = 3
> Level_2_Pixel_Values_Read_As = Real
> structureType = Grid
> unitsCategory = exponent
>
> Hope these help to solve the problems. I appreciate all your
> consideration and help.
>
> Best regards,
> Ehsan
>
> On Sat, Oct 13, 2012 at 1:26 AM, Ehsan Erfani <e.erfani81 at gmail.com
> <mailto:e.erfani81 at gmail.com>> wrote:
>
> 1- I used grads-2.0.a3.oga.1.win32_superpack (GrADS OPenNDAP).
> Also, I tried grads-2.0.1.oga.1-win32_superpack.
> 2- Both of them are opengrads and run in windows.
> 3- First, I want to open hdf data without ctl (I have a lot of
> data and they do not have similar variables). So, I consider using
> sdfopen to open the files.
>
> 4- By using sdfopen, I received these error message for the above
> grads versions, respectively:
>
>
> "gradsdf : SDF file has no discernable X coordinate."
>
> "gadsdf: SDF file has no discernable X coordinate.
> To open this file with GrADS, use a descriptor file with an XDEF
> entry."
>
> 5- I used MODIS hdf files. A typical name of the files can be
> "MOD08_D3.A2011152.051.2011153120457.hdf". I wanted to plot 550 nm
> AOD and deep blue AOD. These data are typical satellite data from
> terra or aqua.
> I do not have access to linux to provide ncdump data. Anyway, the
> message would be very long and I write some first lines
> (containing the dimension and grid data) from the HDF Import Tool
> and write the full message in the end:
> Name: MERRA200.prod.assim.tavg1_2d_lnd_Nx.20000601.hdf
> HDFEOSVersion: HDFEOS_V2.14 StructMetadata.0: GROUP=SwathStructure
> END_GROUP=SwathStructure GROUP=GridStructure GROUP=GRID_1
> GridName="EOSGRID" XDim=540 YDim=361
> UpperLeftPointMtrs=(-180000000.000000,90000000.000000)
> LowerRightMtrs=(180000000.000000,-90000000.000000)
> Projection=GCTP_GEO GridOrigin=HDFE_GD_LL GROUP=Dimension
> OBJECT=Dimension_1 DimensionName="TIME" Size=24
> END_OBJECT=Dimension_1 END_GROUP=Dimension GROUP=DataField
> OBJECT=DataField_1 DataFieldName="GRN" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") 3- I used sdfopen command to open them.
>
> Final word:
> I know that the problem can be due to the dimension, however the
> dimension is defined in the data by XDim and YDim, Time. I wonder
> does anyone successfully use GrADS to open hdf files by sdfopen
> command. Is a certain version of GrADS recommended to do this?
>
> Thank you in advance,
> Ehsan
>
>
> On Fri, Oct 12, 2012 at 10:53 AM, Jennifer Adams
> <jma at cola.iges.org <mailto:jma at cola.iges.org>> wrote:
>
> Your post is missing the following information:
> 1. The version of GrADS you are running
> 2. What operating system you're running it on
> 3. The contents of your ctl file
> 4. The error message you get when you try to open your ctl file
> 5. More information about the grid in your MODIS file,
> especially the output from ncdump (which is often enabled to
> handle HDF files)
> Nobody can help until you provide these things.
> --Jennifer
>
>
>
>
> Name: MERRA200.prod.assim.tavg1_2d_lnd_Nx.20000601.hdf
> HDFEOSVersion: HDFEOS_V2.14 StructMetadata.0: GROUP=SwathStructure
> END_GROUP=SwathStructure GROUP=GridStructure GROUP=GRID_1
> GridName="EOSGRID" XDim=540 YDim=361
> UpperLeftPointMtrs=(-180000000.000000,90000000.000000)
> LowerRightMtrs=(180000000.000000,-90000000.000000)
> Projection=GCTP_GEO GridOrigin=HDFE_GD_LL GROUP=Dimension
> OBJECT=Dimension_1 DimensionName="TIME" Size=24
> END_OBJECT=Dimension_1 END_GROUP=Dimension GROUP=DataField
> OBJECT=DataField_1 DataFieldName="GRN" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_1
> OBJECT=DataField_2 DataFieldName="LAI" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_2
> OBJECT=DataField_3 DataFieldName="GWETROOT" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_3
> OBJECT=DataField_4 DataFieldName="GWETTOP" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_4
> OBJECT=DataField_5 DataFieldName="TPSNOW" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_5
> OBJECT=DataField_6 DataFieldName="TUNST" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_6
> OBJECT=DataField_7 DataFieldName="TSAT" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_7
> OBJECT=DataField_8 DataFieldName="TWLT" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_8
> OBJECT=DataField_9 DataFieldName="PRECSNO" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_9
> OBJECT=DataField_10 DataFieldName="PRECTOT" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_10
> OBJECT=DataField_11 DataFieldName="SNOMAS" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_11
> OBJECT=DataField_12 DataFieldName="SNODP" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_12
> OBJECT=DataField_13 DataFieldName="EVPSOIL" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_13
> OBJECT=DataField_14 DataFieldName="EVPTRNS" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_14
> OBJECT=DataField_15 DataFieldName="EVPINTR" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_15
> OBJECT=DataField_16 DataFieldName="EVPSBLN" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_16
> OBJECT=DataField_17 DataFieldName="RUNOFF" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_17
> OBJECT=DataField_18 DataFieldName="BASEFLOW" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_18
> OBJECT=DataField_19 DataFieldName="SMLAND" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_19
> OBJECT=DataField_20 DataFieldName="FRUNST" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_20
> OBJECT=DataField_21 DataFieldName="FRSAT" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_21
> OBJECT=DataField_22 DataFieldName="FRSNO" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_22
> OBJECT=DataField_23 DataFieldName="FRWLT" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_23
> OBJECT=DataField_24 DataFieldName="PARDF" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_24
> OBJECT=DataField_25 DataFieldName="PARDR" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_25
> OBJECT=DataField_26 DataFieldName="SHLAND" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_26
> OBJECT=DataField_27 DataFieldName="LHLAND" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_27
> OBJECT=DataField_28 DataFieldName="EVLAND" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_28
> OBJECT=DataField_29 DataFieldName="LWLAND" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_29
> OBJECT=DataField_30 DataFieldName="SWLAND" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_30
> OBJECT=DataField_31 DataFieldName="GHLAND" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_31
> OBJECT=DataField_32 DataFieldName="TWLAND" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_32
> OBJECT=DataField_33 DataFieldName="TELAND" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_33
> OBJECT=DataField_34 DataFieldName="WCHANGE" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_34
> OBJECT=DataField_35 DataFieldName="ECHANGE" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_35
> OBJECT=DataField_36 DataFieldName="SPLAND" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_36
> OBJECT=DataField_37 DataFieldName="SPWATR" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_37
> OBJECT=DataField_38 DataFieldName="SPSNOW" DataType=DFNT_FLOAT32
> DimList=("TIME","YDim","XDim") END_OBJECT=DataField_38
> OBJECT=DataField_39 DataFieldName="XDim" DataType=DFNT_FLOAT64
> DimList=("XDim") END_OBJECT=DataField_39 OBJECT=DataField_40
> DataFieldName="YDim" DataType=DFNT_FLOAT64 DimList=("YDim")
> END_OBJECT=DataField_40 OBJECT=DataField_41 DataFieldName="Time"
> DataType=DFNT_FLOAT64 DimList=("TIME") END_OBJECT=DataField_41
> END_GROUP=DataField GROUP=MergedFields
> END_GROUP=MergedFields END_GROUP=GRID_1
> END_GROUP=GridStructure GROUP=PointStructure
> END_GROUP=PointStructure END
>
> On Oct 11, 2012, at 9:53 PM, Ehsan Erfani wrote:
>
>> Hello,
>>
>> I cannot open MODIS (Moderate Resolution Imaging
>> Spectroradiometer) HDF files by grads. I receive this message
>> when I use the sdfopen:
>> "gradsdf : SDF file has no discernable X coordinate."
>>
>> I tried to open by xdfopen without any success. Also, I made
>> a ctl but again it did not help. I appreciate it if you let
>> me know how to open hdf files by GrADS. Thank you.
>>
>> Best regards,
>> Ehsan _______________________________________________
>> gradsusr mailing list
>> gradsusr at gradsusr.org <mailto:gradsusr at gradsusr.org>
>> http://gradsusr.org/mailman/listinfo/gradsusr
>
> --
> Jennifer M. Adams
> IGES/COLA
> 4041 Powder Mill Road, Suite 302
> Calverton, MD 20705
> jma at cola.iges.org <mailto:jma at cola.iges.org>
>
>
>
>
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>
>
>
>
>
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