1GMTDIGITIZE(1) Generic Mapping Tools GMTDIGITIZE(1)
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6 gmtdigitize - Digitizing and Inverse map transformation of map x/y
7 coordinates
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10 gmtdigitize -Jparameters -Rwest/east/south/north[r] [ -A ] [ -Cdevice ]
11 [ -Dlimit ] [ -F ] [ -H[i][nrec] ] [ -Llpi ] [ -M[flag] ] [ -Nnamestem
12 ] [ -S ] [ -V ] [ -Zk|v ] [ -bo[s|S|d|D[ncol]|c[var1/...]] ] [ > out‐
13 put.d ]
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16 gmtdigitize digitizes points from a digitizer via a serial line connec‐
17 tion and computes map coordinates using the specified map projection.
18 The program is interactive and will take you through the setup proce‐
19 dure and how you will digitize points. The program will determine the
20 actual map scale as well as rotation of the paper that is taped to the
21 digitizer table. By default the output will go to stdout.
22 No space between the option flag and the associated arguments.
23 Use upper case for the option flags and lower case for modifiers.
24 -J Selects the map projection. Scale is UNIT/degree, 1:xxxxx, or
26 width in UNIT (upper case modifier). UNIT is cm, inch, or m,
27 depending on the MEASURE_UNIT setting in .gmtdefaults4, but this
28 can be overridden on the command line by appending c, i, or m to
29 the scale/width value. When central meridian is optional,
30 default is center of longitude range on -R option. Default
31 standard parallel is the equator. For map height, max dimen‐
32 sion, or min dimension, append h, +, or - to the width, respec‐
33 tively.
34 More details can be found in the psbasemap man pages.
35 CYLINDRICAL PROJECTIONS:
37 -Jclon0/lat0/scale (Cassini)
39 -Jcyl_stere/[lon0/[lat0/]]scale (Cylindrical Stereographic)
40 -Jj[lon0/]scale (Miller)
41 -Jm[lon0/[lat0/]]scale (Mercator)
42 -Jmlon0/lat0/scale (Mercator - Give meridian and standard paral‐
43 lel)
44 -Jo[a]lon0/lat0/azimuth/scale (Oblique Mercator - point and
45 azimuth)
46 -Jo[b]lon0/lat0/lon1/lat1/scale (Oblique Mercator - two points)
47 -Joclon0/lat0/lonp/latp/scale (Oblique Mercator - point and
48 pole)
49 -Jq[lon0/[lat0/]]scale (Cylindrical Equidistant)
50 -Jtlon0/[lat0/]scale (TM - Transverse Mercator)
51 -Juzone/scale (UTM - Universal Transverse Mercator)
52 -Jy[lon0/[lat0/]]scale (Cylindrical Equal-Area)
53 CONIC PROJECTIONS:
55 -Jblon0/lat0/lat1/lat2/scale (Albers)
57 -Jdlon0/lat0/lat1/lat2/scale (Conic Equidistant)
58 -Jllon0/lat0/lat1/lat2/scale (Lambert Conic Conformal)
59 AZIMUTHAL PROJECTIONS:
61 -Jalon0/lat0[/horizon]/scale (Lambert Azimuthal Equal-Area)
63 -Jelon0/lat0[/horizon]/scale (Azimuthal Equidistant)
64 -Jflon0/lat0[/horizon]/scale (Gnomonic)
65 -Jglon0/lat0[/horizon]/scale (Orthographic)
66 -Jglon0/lat0/altitude/azimuth/tilt/twist/Width/Height/scale
67 (General Perspective).
68 -Jslon0/lat0[/horizon][/slat]/scale (General Stereographic)
69 MISCELLANEOUS PROJECTIONS:
71 -Jh[lon0/]scale (Hammer)
73 -Ji[lon0/]scale (Sinusoidal)
74 -Jkf[lon0/]scale (Eckert IV)
75 -Jk[s][lon0/]scale (Eckert IV)
76 -Jn[lon0/]scale (Robinson)
77 -Jr[lon0/]scale (Winkel Tripel)
78 -Jv[lon0/]scale (Van der Grinten)
79 -Jw[lon0/]scale (Mollweide)
80 NON-GEOGRAPHICAL PROJECTIONS:
82 -Jp[a]scale[/origin][r|z] (Polar coordinates (theta,r))
84 -Jxx-scale[d|l|ppow|t|T][/y-scale[d|l|ppow|t|T]] (Linear, log,
85 and power scaling)
86 For geographic projections you can give 1 as the scale will be
87 solved for anyway.
88 -R xmin, xmax, ymin, and ymax specify the Region of interest. For
90 geographic regions, these limits correspond to west, east,
91 south, and north and you may specify them in decimal degrees or
92 in [+-]dd:mm[:ss.xxx][W|E|S|N] format. Append r if lower left
93 and upper right map coordinates are given instead of w/e/s/n.
94 The two shorthands -Rg and -Rd stand for global domain (0/360
95 and -180/+180 in longitude respectively, with -90/+90 in lati‐
96 tude). For calendar time coordinates you may either give (a)
97 relative time (relative to the selected TIME_EPOCH and in the
98 selected TIME_UNIT; append t to -JX|x), or (b) absolute time of
99 the form [date]T[clock] (append T to -JX|x). At least one of
100 date and clock must be present; the T is always required. The
101 date string must be of the form [-]yyyy[-mm[-dd]] (Gregorian
102 calendar) or yyyy[-Www[-d]] (ISO week calendar), while the clock
103 string must be of the form hh:mm:ss[.xxx]. The use of delim‐
104 iters and their type and positions must be exactly as indicated
105 (however, input, output and plot formats are customizable; see
106 gmtdefaults).
107
109 -A Give an audible signal each time the digitizer mouse/puck is
110 clicked [Default is silent].
111 -C Specify the device (port) to read from [Default is /dev/ttyS0].
113 -D Only output a point if it is further than limit units from the
115 previous point. Append c, i, m, p for cm, inch, meter, or
116 point, respectively [Default is no limit].
117 -F Force the program to ask for 4 arbitrary calibration points
119 [Default is to use the 4 corners of the map, if possible].
120 -H This option allows you to write out any number of header records
122 to the beginning of the output file. Each record will automati‐
123 cally start with a #-character to indicate comment. Headers are
124 not written if multiple output files are selected with -N -M.
125 -L Set the digitizer table resolution in lines per inch [2540].
127 -M Multiple segment file(s). Segments are separated by a special
129 record. For ASCII files the first character must be flag
130 [Default is '>']. For binary files all fields must be NaN and
131 -b must set the number of output columns explicitly. By default
132 the -M setting applies to both input and output. Use -Mi and
133 -Mo to give separate settings.
134 -N Set name for output file(s). If a regular filename is given,
136 then all digitized data will be written to that file. If the
137 file contains a C-format for an integer (i.e., %d) then the file
138 is used as a format statement to create unique filenames based
139 on the current segment number (e.g., line_%d.d will yield files
140 line_0.d, line_1.d, etc). By default, all output is written to
141 stdout. Multiple segment files requires specifying the -M
142 option.
143 -S Suppress points that fall outside the specified map region
145 [Default outputs all points].
146 -V Selects verbose mode, which will send progress reports to stderr
148 [Default runs "silently"]. The program will also duplicate data
149 output to stderr for monitoring.
150 -Z Append v to prompt for a z-value and output it as a third data
152 column. Append k to output the button key as the final data
153 column. Both -Zk and -Zv can be specified. [Default is just 2
154 column x,y output].
155 -bo Selects binary output. Append s for single precision [Default
157 is d (double)]. Uppercase S or D will force byte-swapping.
158 Optionally, append ncol, the number of desired columns in your
159 binary output file.
160
162 To digitize lines from a mercator map made for a given region, and save
163 each line segment in individual files called segment_000.xy, seg‐
164 ment_001.xy etc, try
165 gmtdigitize -R20/50/12/25 -Jm1:1 -M -Nsegment_%3.3d.xy
167 To digitize seismically defined interfaces from a multichannel seismic
169 section, with horizontal distances from 130 to 970, and vertical times
170 from 0 to 10 seconds, write out the button code, and save all line seg‐
171 ment to a single multisegment file, and beep at each click, try
172 gmtdigitize -R130/970/0/10 -Jx1/-1 -M -A -Z > interfaces.d
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176 This applies to the Calcomp DrawingBoard III hooked up to a RedHat
177 Linux workstation. We use /dev/ttyS0 as the serial port and change
178 permissions so that it is world read/write-able. Then, stty -F
179 /dev/ttyS0 evenp will set the terminal settings, which can be checked
180 with stty -F /dev/ttyS0 -a. Setup of digitizer: We use the CalComp
181 2000 ASCII (Save 3) setup, which has:
182 Mode: Point
183 Baud Rate: 9600
184 Data Bits: 7
185 Parity: Even
186 Data Rate: 125 pps
187 Resolution: 200 lpi
188 Output Format: Format 0
189 Emulation: CalComp 2000 ASCII
190 (A)We need to make a slight modification to the Preset No 3 settings:
191 (1) 2450 LPI instead of 200, and (2) None instead of yes for added CR.
192 These modifications can be changed and saved to Preset 3 on the digi‐
193 tizer but a power outage may reset in back to the factory defaults,
194 necessitating a manual reset of those two settings. (B) Setup tty
195 port. stty -F /dev/ttyS0 evenp (C) Run gmtdigitize. Map scale doesnt
196 matter; it is computed from the region and plot size.
197
199 gmtdefaults(l), gmt(l), gmtstitch(l) mapproject(l) project(l)
200GMT 4.3.1 15 May 2008 GMTDIGITIZE(1)