Differences

This shows you the differences between two versions of the page.

--- teaching:m_r:excersize:proj4 [2012/11/07 16:20]
karina [Awk]
+++ teaching:m_r:excersize:proj4 [2021/08/14 04:21] (current)
@@ Line 3: / Line 3: @@
-===== Proj4 =====
+===== Proj.4 =====
 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 is a terminal program / script program.
 Reference: [[http://www.gnu.org/software/gawk/]]
@@ Line 17: / Line 30: @@
 == Download program ==
 ^Windows^Mac^Linux^
-| |[[http://code.google.com/p/rudix/downloads/detail?name=gawk-3.1.8-1.dmg&can=2&q=label%3ARudix-2011|Gnu Awk]]| |
+|[[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>

Technology in Crop Production

User Tools

Site Tools

Differences

Page Tools