I have two files with approximately 12900 and 4400 entries respectively, that I want to join. The files contain location information for all landbased weather observing stations around the globe.
The largest file is updated biweekly, and the smaller once a year or so. The original files can be found here (http://www.wmo.int/pages/prog/www/ois/volume-a/vola-home.htm and
http://weather.rap.ucar.edu/surface/stations.txt). The files I have are already manipulated by me with some mixed awk, sed, and bash script. I use the files to visualize data using the
GEMPAK package, that is freely available from Unidata. The largest file will work with GEMPAK, but only not with its full capability. For this a join is needed.
File 1 contains location information for weather observing stations, where the first 6 digits is the unique station identifier.
The different parameters (station number, station name, country code, latitude longitude, and station elevation) are defined only by its position in the line, i.e. no tabs.
060090 AKRABERG FYR DN 6138 -666 101
060100 VAGA FLOGHAVN DN 6205 -728 88
060110 TORSHAVN DN 6201 -675 55
060120 KIRKJA DN 6231 -631 55
060130 KLAKSVIK HELIPORT DN 6221 -656 75
060160 HORNS REV A DN 5550 786 21
060170 HORNS REV B DN 5558 761 10
060190 SILSTRUP DN 5691 863 0
060210 HANSTHOLM DN 5711 858 0
060220 TYRA OEST DN 5571 480 43
060240 THISTED LUFTHAVN DN 5706 870 8
060290 GROENLANDSHAVNEN DN 5703 1005 0
060300 FLYVESTATION AALBORG DN 5708 985 13
060310 TYLSTRUP DN 5718 995 0
060320 STENHOEJ DN 5736 1033 56
060330 HIRTSHALS DN 5758 995 0
060340 SINDAL FLYVEPLADS DN 5750 1021 28
File 2 contains the unique identifier in File 1 and a second, 4 character identifier (ICAO locator).
060100 EKVG
060220 EKGF
060240 EKTS
060300 EKYT
060340 EKSN
060480 EKHS
060540 EKHO
060600 EKKA
060620 EKSV
060660 EKVJ
060700 EKAH
060780 EKAT
I want to join the two files, so that the resulting file will have the 4 character identifier in the first 4 positions in the line, i.e. the identifier should replace the 4 spaces.
060090 AKRABERG FYR DN 6138 -666 101
EKVG 060100 VAGA FLOGHAVN DN 6205 -728 88
060110 TORSHAVN DN 6201 -675 55
060120 KIRKJA DN 6231 -631 55
060130 KLAKSVIK HELIPORT DN 6221 -656 75
060160 HORNS REV A DN 5550 786 21
060170 HORNS REV B DN 5558 761 10
060190 SILSTRUP DN 5691 863 0
060210 HANSTHOLM DN 5711 858 0
EKGF 060220 TYRA OEST DN 5571 480 43
EKTS 060240 THISTED LUFTHAVN DN 5706 870 8
060290 GROENLANDSHAVNEN DN 5703 1005 0
EKYT 060300 FLYVESTATION AALBORG DN 5708 985 13
060310 TYLSTRUP DN 5718 995 0
060320 STENHOEJ DN 5736 1033 56
060330 HIRTSHALS DN 5758 995 0
EKSN 060340 SINDAL FLYVEPLADS DN 5750 1021 28
Is it possible to accomplish this task with some bash and/or awk script?
Best Answer