bufr_copy examples
To copy only the SYNOP messages from a file
> bufr_copy -w dataCategory=0 in.bufr out.bufr
To copy only the non-SYNOP messages from a file
> bufr_copy -w dataCategory!=0 in.bufr out.bufr
Use the square brackets to insert the value of a key in the name of the output file.
> bufr_copy in.bufr out_[dataCategory].bufr
bufr_dump examples
To dump BUFR messages into a flat JSON format.
> bufr_dump -jf ../data/bufr/aaen_55.bufr
To dump BUFR messages into a structured JSON format.
> bufr_dump -js ../data/bufr/aaen_55.bufr
To dump in a WMO documentation style with hexadecimal octet values (-H).
> bufr_dump -OH ../data/bufr/syno_1.bufr
To add key type information (-t).
> bufr_dump -OtH ../data/bufr/syno_1.bufr
bufr_filter examples
The bufr_filter sequentially processes all bufr messages contained in the input files and applies the rules to each of them. Input messages can be written to the output by using the "write" statement. The write statement can be parameterised so that output is sent to multiple files depending on key values used in the output file name. First we write a rules_file containing the following statement:
Then we create the BUFR file multitype.bufr from three others:write "../data/split/[bufrHeaderCentre:i]_[dataCategory].bufr[editionNumber]";
Applying this rules_file to the "../data/split/multitype.bufr" bufr file we obtain several files in the ../data/split directory containing messages split according to their key valuesmkdir ../data/split cat ../data/bufr/syno_1.bufr ../data/bufr/goes_87.bufr ../data/bufr/gosat.bufr > ../data/split/multitype.bufr
> bufr_filter rules_file ../data/split/multitype.bufr > ls ../data/split 98_0.bufr3 98_3.bufr4 98_5.bufr3 multitype.bufr
The bufr header information can be accessed without unpacking the data. This rules_file:
will result in the following output:print "[bufrHeaderCentre] [bufrHeaderSubCentre] [masterTablesVersionNumber] [localTablesVersionNumber] [numberOfSubsets]";
> bufr_filter rules_file ../data/bufr/syno_multi.bufr 98 0 13 1 1 98 0 13 1 1 98 0 13 1 1
To print values from the data section the messages have to be unpacked. To do that we need to set key unapack to 1. This rules_file:
will print out some data values from the specified SYNOP bufr messages.set unpack=1; print "block=[blockNumber] station=[stationNumber] lat=[latitude] lon=[longitude] t2=[airTemperatureAt2M]";
> bufr_filter rules_file ../data/bufr/syno_multi.bufr block=1 station=1 lat=70.93 lon=-8.67 t2=274.5 block=1 station=3 lat=77 lon=15.5 t2=268.4 block=1 station=7 lat=78.92 lon=11.93 t2=268.5
bufr_filter allows defining new keys with the transient keyword. We will further develop the previous example by creating a new key to combine the block number and the station number into the full WMO station id:
The result is:set unpack=1; transient statid=1000*blockNumber+stationNumber; print "statid=[statid] lat=[latitude] lon=[longitude] t2=[airTemperatureAt2M]";
> bufr_filter rules_file ../data/bufr/syno_multi.bufr statid=1001 lat=70.93 lon=-8.67 t2=274.5 statid=1003 lat=77 lon=15.5 t2=268.4 statid=1007 lat=78.92 lon=11.93 t2=268.5
We can use conditional statements in bufr_filter. The syntax is:
The condition can be made using ==,!= and joining single block conditions with || and &&. The statement can be any valid statement also another nested condition The rules_file below shows how to filter only SYNOP messages with a specific station id:if ( condition ) { block of rules } else { block of rules }set unpack=1; transient statid=1000*blockNumber+stationNumber; if (dataCategory ==0 && statid == 1003) { write out.bufr; }The switch statement is an enhanced version of the if statement. Its syntax is the following:
Each value of each key given as argument to the switch statement is matched against the values specified in the case statements. If there is a match, then the block or rules corresponding to the matching case statement is executed. Otherwise, the default case is executed. The default case is mandatory if the case statements do not cover all the possibilities. The "~" operator can be used to match "anything".switch (key1,key2,...,keyn) { case val11,val12,...,val1n: # block of rules; case val21,val22,...,val2n: # block of rules; default: # [ block of rules ] }To access the keys' attributes use the -> operator. The example below prints the attributes of key pressure from a SYNOP bufr message.
The result is:print "pressure=[pressure] [pressure->units]"; print "pressure->code=[pressure->code!06d]"; print "pressure->scale=[pressure->scale]"; print "pressure->reference=[pressure->reference]"; print "pressure->width=[pressure->width]"; print "pressure->percentConfidence=[pressure->percentConfidence] [pressure->percentConfidence->units]"; print "pressure->percentConfidence->code=[pressure->percentConfidence->code!06d]"; print "pressure->percentConfidence->scale=[pressure->percentConfidence->scale]"; print "pressure->percentConfidence->reference=[pressure->percentConfidence->reference]"; print "pressure->percentConfidence->width=[pressure->percentConfidence->width]";
> bufr_filter rules_file ../data/bufr/syno_1.bufr pressure=undef undef ERROR: Key/value not found </p></li><br /></ol><h2>bufr_get examples</h2><ol><li><p> bufr_get fails if a key is not found. <ac:structured-macro ac:name="code"><ac:plain-text-body><![CDATA[ > bufr_get -p centreName ../data/bufr/syno_1.bufr no messages found in ../data/bufr/syno_1.bufr
bufr_ls examples
Without options a default list of keys is printed. The default list can be different depending on the type of BUFR message.
The result is:> bufr_ls ../data/bufr/syno_multi.bufr
../data/bufr/syno_multi.bufr centre masterTablesVersionNumber localTablesVersionNumber rdbType rdbSubtype rdbtimeYear rdbtimeMonth typicalDate typicalTime numberOfSubsets localLatitude localLongitude 98 13 1 1 1 2009 1 20090124 120000 1 70.93 -8.67 98 13 1 1 1 2009 1 20090124 120000 1 77 15.5 98 13 1 1 1 2009 1 20090124 120000 1 78.92 11.93 3 of 3 messages in ../data/bufr/syno_multi.bufr 3 of 3 total messages in 1 files
It is allowed to use wildcards in filenames.
> bufr_ls ../data/bufr/syno_*.bufr
To list only a specific set of keys use the -p option.
> bufr_ls -p totalLength,bufrHeaderCentre,bufrHeaderSubCentre ../data/bufr/syno_multi.bufr
To list only a subset of messages use the -w (where option). Only the 12 UTC messages are listed with the following line.
> bufr_ls -w typicalTime="120000" ../data/bufr/syno_*.bufr
All the non-12 UTC messages are listed as follows:
> bufr_ls -w typicalTime!="120000" ../data/bufr/syno_*.bufr
To list only the scond message from a BUFR file:
> bufr_ls -w count=2 ../data/bufr/syno_multi.bufr
bufr_set examples
Set key bufrHeaderCentre in the header and print its value after the change:
> bufr_set -v -p bufrHeaderCentre -s bufrHeaderCentre=222 ../data/bufr/syno_1.bufr out.bufr