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teaching:m_r:excersize:proj4 [2012/11/07 15:59]
karina [Awk] 		teaching:m_r:excersize:proj4 [2021/08/14 04:21] (current)
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-===== Proj4 =====+===== Proj.4 =====
 Reference: [[https://trac.osgeo.org/proj/]] Reference: [[https://trac.osgeo.org/proj/]]
 +
 +
 +PROJ.4 is a library for performing conversions between cartographic projections. The library is based on the work of Gerald Evenden at the USGS,[2] but is now an OSGeo project maintained by Frank Warmerdam. The library also ships with executables for performing these transformations from the command line. (Reference: [[http://en.wikipedia.org/wiki/PROJ.4]])
 +
 +
 +
 +== Download program ==
 +^Windows^Mac^Linux^
 +|[[http://trac.osgeo.org/mapserver/wiki/WindowsProjHowto|Proj.4]] |  |[[http://linux.softpedia.com/get/Programming/Libraries/PROJ-4-19030.shtml|Proj.4]] |
 +
 +
  
 ===== Awk ===== ===== Awk =====
 +Awk is a terminal program / script program. 
 +
 Reference: [[http://www.gnu.org/software/gawk/]] Reference: [[http://www.gnu.org/software/gawk/]]
  
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 Find the manual here: [[http://www.gnu.org/software/gawk/manual/]] Find the manual here: [[http://www.gnu.org/software/gawk/manual/]]
 +
 +== Download program ==
 +^Windows^Mac^Linux^
 +|[[http://gnuwin32.sourceforge.net/packages/gawk.htm|Gnu Awk]] |[[http://code.google.com/p/rudix/downloads/detail?name=gawk-3.1.8-1.dmg&can=2&q=label%3ARudix-2011|Gnu Awk]]\\ open gawk.pkg|[[http://linux.softpedia.com/get/Text-Editing-Processing/Filters/GNU-awk-207.shtml|Gnu Awk]] |
 +
 +===== Awk/proj4 script =====
 +Script that convert gga-strings to UTM co-ordinates.
 +
 +
 +<file bash ggacs2cs.awk> 
 +#!/usr/bin/awk -f
 +function usage(){
 +  print "purpose: convert geographical/projected coordinates from NMEA input"
 +  print "default: parses GGA and transforms coordinates from WGS84 to UTM 32 N"
 +  print "options [-v OPT=value]:"
 +  print "EPSGFROM=4326 (epsg code to convert from)"
 +  print "EPSGTO=25832 (epsg code to convert to)"
 +  print "MYFS=\",\" (field separator)"
 +  print "CNV=false (convert to pseudo NMEA message with converted coordinates)"
 +  print "NFN=3 (input field latitude)"
 +  print "EFN=5 (input field longitude)"
 +  print "ECHO=false (echo NMEA messages)"
 +  print "PRINT2FILE=false (set to false in order not to write to file)"
 +  print "OUTPUTFILE=ggacs2cs (filename of the output file)"
 +  
 +}
 +#Windows command: gawk -f ggacs2cs.awk -v ECHO=true PRINT2FILE=true OUTPUTFILE=utm_row4_adana EPSGTO=32636 ggaLog.log
 +#Windows command: gawk -f ggacs2cs.awk -v PRINT2FILE=true OUTPUTFILE=gga_l_u EPSGTO=32636 GGAlinksoben.log
 +#EPSG:32636: WGS 84 / UTM zone 36N
 +
 +# TODO: feed all coordinates to cs2cs in one large chunk, not line per line
 +# TODO: use optarg: http://snap.nlc.dcccd.edu/reference/awkref/gawk_17.html
 +BEGIN{
 +<<<<<<< .mine
 +CONVFMT="%.12f"
 +=======
 +CONVFMT="%.10f"
 +>>>>>>> .r1275
 +#     while ((c = getopt(ARGC, ARGV, "h")) != -1) {
 +#         if (c == "h") {
 +#             usage()
 +#         }# else if (c == "c") { # TODO implement other options here
 +        #}
 +
 +if(MYFS==""){
 +  FS=","
 +}
 +  OFS=FS
 +  if (EPSGTO==""){
 +    EPSGTO="25832" # 25832: # ETRS89 / UTM zone 32N <25832> +proj=utm +zone=32 +ellps=GRS80 +units=m +no_defs  <>
 +  }
 +  if (EPSGFROM==""){
 +    EPSGFROM="4326"
 +  }
 +  if (CNV==""){ # if CNV="true" then a fake string is created with the transformed coordinates
 +    CNV="false" 
 +  }
 +  if(NFN==""){NFN=3}
 +  if(EFN==""){EFN=5}
 +  if(HFN==""){HFN=10}
 +  if(ECHO==""){ECHO="false"} # echo NMEA as seen? set with -v ECHO=true
 +  if(PRINT2FILE==""){PRINT2FILE="false"}
 +  if(OUTPUTFILE==""){OUTPUTFILE="ggacs2cs"}
 +}
 +
 +function nmea2dd(nmeacoord){
 +  dn=int(nmeacoord/100);
 +  return dn+((nmeacoord-(dn*100.0))/60)
 +}
 +function cs2cs(coordarray){
 +  CMD="echo "coordarray[2]" "coordarray[1]" "coordarray[3]" | cs2cs -f \"%.6f\" +init=epsg:"coordarray[4]" +to +init=epsg:"coordarray[5]
 +   #print CMD
 +  gkarray[0]=""
 +  CMD | getline TRANSFCOORD
 +#   printf "begin"TRANSFCOORD"end"
 +  split(TRANSFCOORD, gkarray, "\t")
 +  split(gkarray[2],D," ")
 +  # print  C[0]
 +  # GKR=C[1]
 +  # GKH=D[1]
 +  coordarray[7]=gkarray[1]
 +  coordarray[6] = D[1] #northing
 +  coordarray[8] = D[2] #easting
 +#   print "\\debug wgs2gk3: " coordarray[1] FS coordarray[2] FS coordarray[3]  FS coordarray[4] FS coordarray[5] FS coordarray[6]
 +#   return gkarray
 +}
 +
 +# function wgs84toepsg(coord_n_e_h_to){
 +#   CMD="echo "coord_n_e_h_to[1]" "coord_n_e_h_to[2]" "coord_n_e_h_to[3]" | cs2cs -f \"%.3f\" +proj=latlong +datum=WGS84 +to +EPSG:"coord_n_e_h_to[4]" "
 +#   # print CMD
 +#   resarray[0]=""
 +#   CMD | getline TRANSFCOORD
 +# #   printf "begin"TRANSFCOORD"end"
 +#   split(TRANSFCOORD, splitarray, "\t")
 +#   split(splitarray[2],D," ")
 +#   # print  C[0]
 +#   # GKR=C[1]
 +#   # GKH=D[1]
 +#   resarray[1]=splitarray[1]
 +#   resarray[2] = D[1]
 +#   resarray[3] = D[2]
 +#    print "\\debug wgs84toepsg: " resarray[1] FS resarray[2] FS resarray[3]
 +#   return resarray
 +# }
 +{if (ECHO!="false"){print;}
 +#if (true){
 +# for (i=1;i<=NF;i++){
 +# print i"\t"$i
 +# }
 +#}
 +}
 +/GGA/{
 +#   $GPGGA,131329.00,4842.71443089,N,00912.27614062,E,4,07,1.3,437.834,M,0.000,M,0.0,0000*70
 +  transarray[0]=""
 +  transarray[1]=nmea2dd($NFN) # ddlat
 +  transarray[2]=nmea2dd($EFN) # ddlon
 +  transarray[3]=$HFN # wgsheight
 +  transarray[4]=EPSGFROM
 +  transarray[5]=EPSGTO
 +#   transarray[4]=EPSGCODE
 +  cs2cs(transarray)
 +  if(CNV!="false"){ # print pseudo string with transformed coordinates
 +    $1="$CCONV"
 +    $NFN=transarray[6]
 +    $EFN=transarray[7]
 +    $HFN=transarray[8]
 +    print $0
 +  }else
 +  print transarray[6] FS transarray[7] FS transarray[8]
 +  #write to file: works in windows
 +  if(PRINT2FILE=="true"){
 + #{print transarray[6] FS transarray[7] FS transarray[8] > OUTPUTFILE".log"}
 + #northing,easting
 + {print transarray[1] FS transarray[2] FS transarray[3] > OUTPUTFILE".log"}
 +
 +  }
 +}
 +
 +</file>
teaching/m_r/excersize/proj4.1352300391.txt.gz · Last modified: 2021/08/14 04:20 (external edit)

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