1PSCONTOUR(1) Generic Mapping Tools PSCONTOUR(1)
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6 pscontour - Contour xyz-data by direct triangulation [method]
7
9 pscontour xyzfile -Ccptfile -Jparameters -Rwest/east/south/north[r] [
10 -A[-][labelinfo] ] [ -B[p|s]parameters ] [ -D[dumpfile] ] [
11 -Eview_az/view_el ] [ -G[d|f|n|l|L|x|X]params ] [ -H[i][nrec] ] [ -I ]
12 [ -K ] [ -Lpen ] [ -M[flag] ] [ -N ] [ -O ] [ -P ] [ -S ] [ -Tindexfile
13 ] [ -U[just/dx/dy/][c|label] ] [ -V ] [ -W[+]pen ] [ -X[a|c|r][x-
14 shift[u]] ] [ -Y[a|c|r][y-shift[u]] ] [ -ccopies ] [ -:[i|o] ] [
15 -b[i|o][s|S|d|D[ncol]|c[var1/...]] ]
16
18 pscontour reads an ASCII [or binary] xyz-file and produces a raw con‐
19 tour plot by triangulation. By default, the optimal Delaunay triangu‐
20 lation is performed (using either Shewchuk's [1996] or Watson's [1982]
21 method as selected during GMT installation; type pscontour - to see
22 which method is selected), but the user may optionally provide a second
23 file with network information, such as a triangular mesh used for
24 finite element modeling. In addition to contours, the area between
25 contours may be painted according to the color palette file.
26 xyzfile
28 Raw ASCII (or binary, see -b) xyz data to be contoured.
29 -C name of the color palette file. Must have discrete colors if
31 you want to paint the surface (-I). Only contours that have
32 annotation flags set will be annotated.
33 -J Selects the map projection. Scale is UNIT/degree, 1:xxxxx, or
35 width in UNIT (upper case modifier). UNIT is cm, inch, or m,
36 depending on the MEASURE_UNIT setting in .gmtdefaults4, but this
37 can be overridden on the command line by appending c, i, or m to
38 the scale/width value. When central meridian is optional,
39 default is center of longitude range on -R option. Default
40 standard parallel is the equator. For map height, max dimen‐
41 sion, or min dimension, append h, +, or - to the width, respec‐
42 tively.
43 More details can be found in the psbasemap man pages.
44 CYLINDRICAL PROJECTIONS:
46 -Jclon0/lat0/scale (Cassini)
48 -Jcyl_stere/[lon0/[lat0/]]scale (Cylindrical Stereographic)
49 -Jj[lon0/]scale (Miller)
50 -Jm[lon0/[lat0/]]scale (Mercator)
51 -Jmlon0/lat0/scale (Mercator - Give meridian and standard paral‐
52 lel)
53 -Jo[a]lon0/lat0/azimuth/scale (Oblique Mercator - point and
54 azimuth)
55 -Jo[b]lon0/lat0/lon1/lat1/scale (Oblique Mercator - two points)
56 -Joclon0/lat0/lonp/latp/scale (Oblique Mercator - point and
57 pole)
58 -Jq[lon0/[lat0/]]scale (Cylindrical Equidistant)
59 -Jtlon0/[lat0/]scale (TM - Transverse Mercator)
60 -Juzone/scale (UTM - Universal Transverse Mercator)
61 -Jy[lon0/[lat0/]]scale (Cylindrical Equal-Area)
62 CONIC PROJECTIONS:
64 -Jblon0/lat0/lat1/lat2/scale (Albers)
66 -Jdlon0/lat0/lat1/lat2/scale (Conic Equidistant)
67 -Jllon0/lat0/lat1/lat2/scale (Lambert Conic Conformal)
68 AZIMUTHAL PROJECTIONS:
70 -Jalon0/lat0[/horizon]/scale (Lambert Azimuthal Equal-Area)
72 -Jelon0/lat0[/horizon]/scale (Azimuthal Equidistant)
73 -Jflon0/lat0[/horizon]/scale (Gnomonic)
74 -Jglon0/lat0[/horizon]/scale (Orthographic)
75 -Jglon0/lat0/altitude/azimuth/tilt/twist/Width/Height/scale
76 (General Perspective).
77 -Jslon0/lat0[/horizon][/slat]/scale (General Stereographic)
78 MISCELLANEOUS PROJECTIONS:
80 -Jh[lon0/]scale (Hammer)
82 -Ji[lon0/]scale (Sinusoidal)
83 -Jkf[lon0/]scale (Eckert IV)
84 -Jk[s][lon0/]scale (Eckert IV)
85 -Jn[lon0/]scale (Robinson)
86 -Jr[lon0/]scale (Winkel Tripel)
87 -Jv[lon0/]scale (Van der Grinten)
88 -Jw[lon0/]scale (Mollweide)
89 NON-GEOGRAPHICAL PROJECTIONS:
91 -Jp[a]scale[/origin][r|z] (Polar coordinates (theta,r))
93 -Jxx-scale[d|l|ppow|t|T][/y-scale[d|l|ppow|t|T]] (Linear, log,
94 and power scaling)
95 -R xmin, xmax, ymin, and ymax specify the Region of interest. For
97 geographic regions, these limits correspond to west, east,
98 south, and north and you may specify them in decimal degrees or
99 in [+-]dd:mm[:ss.xxx][W|E|S|N] format. Append r if lower left
100 and upper right map coordinates are given instead of w/e/s/n.
101 The two shorthands -Rg and -Rd stand for global domain (0/360
102 and -180/+180 in longitude respectively, with -90/+90 in lati‐
103 tude). For calendar time coordinates you may either give (a)
104 relative time (relative to the selected TIME_EPOCH and in the
105 selected TIME_UNIT; append t to -JX|x), or (b) absolute time of
106 the form [date]T[clock] (append T to -JX|x). At least one of
107 date and clock must be present; the T is always required. The
108 date string must be of the form [-]yyyy[-mm[-dd]] (Gregorian
109 calendar) or yyyy[-Www[-d]] (ISO week calendar), while the clock
110 string must be of the form hh:mm:ss[.xxx]. The use of delim‐
111 iters and their type and positions must be exactly as indicated
112 (however, input, output and plot formats are customizable; see
113 gmtdefaults).
114
116 No space between the option flag and the associated arguments.
117 -A Give - to disable all annotations. The optional labelinfo con‐
119 trols the specifics of the label formatting and consists of a
120 concatenated string made up of any of the following control
121 arguments:
122 +aangle
124 For annotations at a fixed angle, +an for line-normal, or
125 +ap for line-parallel [Default].
126 +cdx[/dy]
128 Sets the clearance between label and optional text box.
129 Append c|i|m|p to specify the unit or % to indicate a
130 percentage of the label font size [15%].
131 +d Turns on debug which will draw helper points and lines to
133 illustrate the workings of the quoted line setup.
134 +ffont Sets the desired font [Default ANNOT_FONT_PRIMARY].
136 +g[color]
138 Selects opaque text boxes [Default is transparent];
139 optionally specify the color [Default is PAGE_COLOR].
140 (See SPECIFYING COLOR below).
141 +jjust Sets label justification [Default is MC]. Ignored when
143 -SqN|n+|-1 is used.
144 +kcolor
146 Sets color of text labels [Default is COLOR_BACKGROUND].
147 (See SPECIFYING COLOR below).
148 +llabel
150 Sets the constant label text.
151 +Lflag Sets the label text according to the specified flag:
153 +Lh Take the label from the current multisegment
155 header (first scan for an embedded -Llabel option,
156 if not use the first word following the segment
157 flag). For multiple-word labels, enclose entire
158 label in double quotes.
159 +Ld Take the Cartesian plot distances along the line
161 as the label; append c|i|m|p as the unit [Default
162 is MEASURE_UNIT].
163 +LD Calculate actual map distances; append d|e|k|m|n
165 as the unit [Default is d(egrees), unless label
166 placement was based on map distances along the
167 lines in which case we use the same unit specified
168 for that algorithm]. Requires a map projection to
169 be used.
170 +Lf Use text after the 2nd column in the fixed label
172 location file as the label. Requires the fixed
173 label location setting.
174 +Lx As +Lh but use the headers in the xfile.d instead.
176 Requires the crossing file option.
177 +ndx[/dy]
179 Nudges the placement of labels by the specified amount
180 (append c|i|m|p to specify the units). Increments are
181 considered in the coordinate system defined by the orien‐
182 tation of the line; use +N to force increments in the
183 plot x/y coordinates system [no nudging].
184 +o Selects rounded rectangular text box [Default is rectan‐
186 gular]. Not applicable for curved text (+v) and only
187 makes sense for opaque text boxes.
188 +p[pen]
190 Draws the outline of text boxsets [Default is no out‐
191 line]; optionally specify pen for outline [Default is
192 width = 0.25p, color = black, texture = solid]. (See
193 SPECIFYING PENS below).
194 +rmin_rad
196 Will not place labels where the line's radius of curva‐
197 ture is less than min_rad [Default is 0].
198 +ssize Sets the desired font size in points [Default is 9].
200 +uunit Appends unit to all line labels. If unit starts with a
202 leading hypen (-) then there will be no space between
203 label value and the unit. [Default is no unit].
204 +v Specifies curved labels following the path [Default is
206 straight labels].
207 +w Specifies how many (x, y) points will be used to estimate
209 label angles [Default is 10].
210 +=prefix
212 Prepends prefix to all line labels. If prefix starts
213 with a leading hypen (-) then there will be no space
214 between label value and the prefix. [Default is no pre‐
215 fix].
216 -B Sets map boundary annotation and tickmark intervals; see the
218 psbasemap man page for all the details.
219 -D Dump the (x,y,z) coordinates of each contour to separate files,
221 one for each contour segment. The files will be named dump‐
222 file_cont_segment[_i].xyz, where cont is the contour value and
223 segment is a running segment number for each contour interval
224 (for closed contours we append _i.) However, when -M is used in
225 conjunction with -D a single multisegment file is created
226 instead.
227 -E Sets the view point by specifying azimuth and elevation in
229 degrees. [Default is 180/90].
230 -G Controls the placement of labels along the contours. Choose
232 among five controlling algorithms:
233 -Gddist[c|i|m|p] or -GDdist[d|e|k|m|n]
235 For lower case d, give distances between labels on the
236 plot in your preferred measurement unit c (cm), i (inch),
237 m (meter), or p (points), while for upper case D, specify
238 distances in map units and append the unit; choose among
239 e (m), k (km), m (mile), n (nautical mile), or d (spheri‐
240 cal degree). [Default is 10c or 4i].
241 -Gfffile.d
243 Reads the ascii file ffile.d and places labels at loca‐
244 tions in the file that matches locations along the con‐
245 tours. Inexact mathces and points outside the region are
246 skipped.
247 -Gl|Lline1[,line2,...]
249 Give start and stop coordinates for one or more comma-
250 separated straight line segments. Labels will be placed
251 where these lines intersect the contours. The format of
252 each line specification is start/stop, where start and
253 stop are either a specified point lon/lat or a 2-charac‐
254 ter XY key that uses the justification format employed in
255 pstext to indicate a point on the map, given as
256 [LCR][BMT]. -GL will interpret the point pairs as defin‐
257 ing great circles [Default is straight line].
258 -Gnn_label
260 Specifies the number of equidistant labels for contours
261 line [1]. Upper case -GN starts labeling exactly at the
262 start of the line [Default centers them along the line].
263 -GN-1 places one justified label at start, while -GN+1
264 places one justified label at the end of contours.
265 Optionally, append /min_dist[c|i|m|p] to enforce that a
266 minimum distance separation between successive labels is
267 enforced.
268 -Gx|Xxfile.d
270 Reads the multi-segment file xfile.d and places labels at
271 the intersections between the contours and the lines inx‐
272 file.d. -GX will resample the lines first along great-
273 circle arcs.
274 In addition, you may optionally append :radius[c|i|m|p] to set a mini‐
275 mum label separation in the x-y plane [no limitation].
276 -H Input file(s) has Header record(s). Number of header records
278 can be changed by editing your .gmtdefaults4 file. If used, GMT
279 default is 1 header record. Use -Hi if only input data should
280 have header records [Default will write out header records if
281 the input data have them]. Blank lines and lines starting with #
282 are always skipped.
283 -I Color the triangles using the color palette table.
285 -Jz Sets the vertical scaling (for 3-D maps). Same syntax as -Jx.
287 -K More PostScript code will be appended later [Default terminates
289 the plot system].
290 -L Draw the underlying triangular mesh using the specified pen
292 attributes [Default is no mesh]. (See SPECIFYING PENS below).
293 -M When used in conjunction with -D a single multisegment file is
295 created, and each contour section is preceded by a header record
296 whose first column is flag followed by the contour level.
297 -N Do NOT clip contours or image at the boundaries [Default will
299 clip to fit inside region -R].
300 -O Selects Overlay plot mode [Default initializes a new plot sys‐
302 tem].
303 -P Selects Portrait plotting mode [Default is Landscape, see gmtde‐
305 faults to change this].
306 -S Skip all input xyz points that fall outside the region [Default
308 uses all the data in the triangulation].
309 -T Give name of file with network information. Each record must
311 contain triplets of node numbers for a triangle [Default com‐
312 putes these using Delaunay triangulation (see triangulate)].
313 -U Draw Unix System time stamp on plot. By adding just/dx/dy/, the
315 user may specify the justification of the stamp and where the
316 stamp should fall on the page relative to lower left corner of
317 the plot. For example, BL/0/0 will align the lower left corner
318 of the time stamp with the lower left corner of the plot.
319 Optionally, append a label, or c (which will plot the command
320 string.). The GMT parameters UNIX_TIME, UNIX_TIME_POS, and
321 UNIX_TIME_FORMAT can affect the appearance; see the gmtdefaults
322 man page for details. The time string will be in the locale set
323 by the environment variable TZ (generally local time).
324 -V Selects verbose mode, which will send progress reports to stderr
326 [Default runs "silently"].
327 -W Select contouring and set contour pen attributes. If the + flag
329 is set then the contour lines are colored according to the cpt
330 file (see -C). (See SPECIFYING PENS below).
331 -X -Y Shift plot origin relative to the current origin by (x-shift,y-
333 shift) and optionally append the length unit (c, i, m, p). You
334 can prepend a to shift the origin back to the original position
335 after plotting, or prepend r [Default] to reset the current
336 origin to the new location. If -O is used then the default (x-
337 shift,y-shift) is (0,0), otherwise it is (r1i, r1i) or (r2.5c,
338 r2.5c). Alternatively, give c to align the center coordinate (x
339 or y) of the plot with the center of the page based on current
340 page size.
341 -: Toggles between (longitude,latitude) and (latitude,longitude)
343 input and/or output. [Default is (longitude,latitude)]. Append
344 i to select input only or o to select output only. [Default
345 affects both].
346 -bi Selects binary input. Append s for single precision [Default is
348 d (double)]. Uppercase S or D will force byte-swapping.
349 Optionally, append ncol, the number of columns in your binary
350 input file if it exceeds the columns needed by the program. Or
351 append c if the input file is netCDF. Optionally, append
352 var1/var2/... to specify the variables to be read. [Default is
353 3 input columns]. Use 4-byte integer triplets for node ids
354 (-T).
355 -bo Selects binary output. Append s for single precision [Default
357 is d (double)]. Uppercase S or D will force byte-swapping.
358 Optionally, append ncol, the number of desired columns in your
359 binary output file. [Default is 3 output columns].
360 -c Specifies the number of plot copies. [Default is 1].
362 SPECIFYING PENS
364 pen The attributes of lines and symbol outlines as defined by pen is
365 a comma delimetered list of width, color and texture, each of
366 which is optional. width can be indicated as a measure (points,
367 centimeters, inches) or as faint, thin[ner|nest], thick[er|est],
368 fat[ter|test], or obese. color specifies a grey shade or color
369 (see SPECIFYING COLOR below). texture is a combination of
370 dashes `-' and dots `.'.
371 SPECIFYING COLOR
373 color The color of lines, areas and patterns can be specified by a
374 valid color name; by a grey shade (in the range 0-255); by a
375 decimal color code (r/g/b, each in range 0-255; h-s-v, ranges
376 0-360, 0-1, 0-1; or c/m/y/k, each in range 0-1); or by a hexa‐
377 decimal color code (#rrggbb, as used in HTML). See the gmtcol‐
378 ors manpage for more information and a full list of color names.
379
381 To make a raw contour plot from the file topo.xyz and drawing the con‐
382 tours (pen = 2) given in the color palette file topo.cpt on a Lambert
383 map at 0.5 inch/degree along the standard parallels 18 and 24, use
384 pscontour topo.xyz -R320/330/20/30 -Jl18/24/0.5i -Ctopo.cpt -W0.5p >
386 topo.ps
387 To create a color PostScript plot of the numerical temperature solution
389 obtained on a triangular mesh whose node coordinates and temperatures
390 are stored in temp.xyz and mesh arrangement is given by the file
391 mesh.ijk, using the colors in temp.cpt, run
392 pscontour temp.xyz -R0/150/0/100 -Jx0.1 -Ctemp.cpt -G -W0.25p > temp.ps
394
396 Sometimes there will appear to be thin lines of the wrong color in the
397 image. This is a round-off problem which may be remedied by using a
398 higher value of DOTS_PR_INCH in the .gmtdefaults4 file.
399
401 GMT(1), grdcontour(1), grdimage(1), nearneighbor(1), psbasemap(1), pss‐
402 cale(1), surface(1), triangulate(1)
403
405 Watson, D. F., 1982, Acord: Automatic contouring of raw data, Comp. &
406 Geosci., 8, 97-101.
407 Shewchuk, J. R., 1996, Triangle: Engineering a 2D Quality Mesh Genera‐
408 tor and Delaunay Triangulator, First Workshop on Applied Computational
409 Geometry (Philadelphia, PA), 124-133, ACM, May 1996.
410 www.cs.cmu.edu/~quake/triangle.html
411GMT 4.3.1 15 May 2008 PSCONTOUR(1)