1PSCONTOUR(1) GMT PSCONTOUR(1)
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6 pscontour - Contour table data by direct triangulation [method]
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9 pscontour [ table ] -C[+]cpt -Jparameters
10 -Rwest/east/south/north[/zmin/zmax][+r] [
11 -A[-|[+]annot_int][labelinfo] ] [ -B[p|s]parameters ] [ -D[template]
12 ] [ -Eindexfile ] [ -G[d|f|n|l|L|x|X]params ] [ -I ] [ -Jz|Zparame‐
13 ters ] [ -K ] [ -Lpen ] [ -N ] [ -O ] [ -P ] [ -Qcut ] [ -S[p|t]
14 ] [ -T[+|-][+dgap[/length]][+l[labels]] ] [ -U[stamp] ] [ -V[level]
15 ] [ -W[type]pen ][+c[l|f]] [ -Xx_offset ] [ -Yy_offset ] [ -bbinary
16 ] [ -dnodata ] [ -eregexp ] [ -hheaders ] [ -iflags ] [ -pflags ] [
17 -ttransp ] [ -:[i|o] ]
18 Note: No space is allowed between the option flag and the associated
20 arguments.
21
23 pscontour reads an ASCII [or binary] table and produces a raw contour
24 plot by triangulation. By default, the optimal Delaunay triangulation
25 is performed (using either Shewchuk's [1996] or Watson's [1982] method
26 as selected during GMT installation; type pscontour - to see which
27 method is selected), but the user may optionally provide a second file
28 with network information, such as a triangular mesh used for finite
29 element modeling. In addition to contours, the area between contours
30 may be painted according to the CPT. Alternatively, the x/y/z posi‐
31 tions of the contour lines may be saved to one or more output files (or
32 stdout) and no plot is produced.
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35 -C[+]cont_int
36 The contours to be drawn may be specified in one of three possi‐
37 ble ways:
38 1. If cont_int has the suffix ".cpt" and can be opened as a
40 file, it is assumed to be a CPT. The color boundaries are
41 then used as contour levels. If the CPT has annotation flags
42 in the last column then those contours will be annotated. By
43 default all contours are labeled; use -A- to disable all
44 annotations.
45 2. If cont_int is a file but not a CPT, it is expected to con‐
47 tain contour levels in column 1 and a C(ontour) OR A(nnotate)
48 in col 2. The levels marked C (or c) are contoured, the lev‐
49 els marked A (or a) are contoured and annotated. Optionally,
50 a third column may be present and contain the fixed annota‐
51 tion angle for this contour level.
52 3. If no file is found, then cont_int is interpreted as a con‐
54 stant contour interval. However, if prepended with the + sign
55 the cont_int is taken as meaning draw that single contour.
56 The -A option offers the same possibility so they may be used
57 together to plot only one annotated and one non-annotated
58 contour. If -A is set and -C is not, then the contour inter‐
59 val is set equal to the specified annotation interval.
60 If a file is given and -T is set, then only contours marked with
62 upper case C or A will have tick-marks. In all cases the contour
63 values have the same units as the file.
64 -Jparameters (more ...)
66 Select map projection.
67 -Rxmin/xmax/ymin/ymax[+r][+uunit] (more ...)
69 Specify the region of interest.
70 For perspective view p, optionally append /zmin/zmax. (more ...)
72
74 table One or more ASCII (or binary, see -bi[ncols][type]) data table
75 file(s) holding a number of data columns. If no tables are given
76 then we read from standard input.
77 -A[-|[+]annot_int][labelinfo]
79 annot_int is annotation interval in data units; it is ignored if
80 contour levels are given in a file. [Default is no annotations].
81 Append - to disable all annotations implied by -C. Alternatively
82 prepend + to the annotation interval to plot that as a single
83 contour. The optional labelinfo controls the specifics of the
84 label formatting and consists of a concatenated string made up
85 of any of the following control arguments:
86 +aangle
88 For annotations at a fixed angle, +an for contour-normal, or
89 +ap for contour-parallel [Default]. For +ap, you may option‐
90 ally append u for up-hill and d for down-hill cartographic
91 annotations.
92 +cdx[/dy]
94 Sets the clearance between label and optional text box.
95 Append c|i|p to specify the unit or % to indicate a percent‐
96 age of the label font size [15%].
97 +d Turns on debug which will draw helper points and lines to
99 illustrate the workings of the contour line setup.
100 +e Delay the plotting of the text. This is used to build a clip
102 path based on the text, then lay down other overlays while
103 that clip path is in effect, then turning of clipping with
104 psclip -Cs which finally plots the original text.
105 +ffont Sets the desired font [Default FONT_ANNOT_PRIMARY with its
107 size changed to 9p].
108 +g[color]
110 Selects opaque text boxes [Default is transparent]; option‐
111 ally specify the color [Default is PS_PAGE_COLOR].
112 +jjust Sets label justification [Default is MC].
114 +ndx[/dy]
116 Nudges the placement of labels by the specified amount
117 (append c|i|p to specify the units). Increments are consid‐
118 ered in the coordinate system defined by the orientation of
119 the contour; use +N to force increments in the plot x/y coor‐
120 dinates system [no nudging]. Not allowed with +v.
121 +o Selects rounded rectangular text box [Default is rectangu‐
123 lar]. Not applicable for curved text (+v) and only makes
124 sense for opaque text boxes.
125 +p[pen]
127 Draws the outline of text boxes [Default is no outline];
128 optionally specify pen for outline [Default is width = 0.25p,
129 color = black, style = solid].
130 +rmin_rad
132 Will not place labels where the contours's radius of curva‐
133 ture is less than min_rad [Default is 0].
134 +t[file]
136 Saves contour label x, y, angle, and text to file [Con‐
137 tour_labels.txt].
138 +uunit Appends unit to all contour labels. [Default is no unit]. If
140 z is appended we use the z-unit from the grdfile.
141 +v Specifies curved labels following the contour [Default is
143 straight labels].
144 +w Specifies how many (x,y) points will be used to estimate
146 label angles [automatic].
147 +=prefix
149 Prepends prefix to all contour labels. [Default is no pre‐
150 fix].
151 -B[p|s]parameters (more ...)
153 Set map boundary frame and axes attributes.
154 -D[template]
156 Dump the (x,y,z) coordinates of each contour to one or more output
157 files (or stdout if template is not given). No plotting will take
158 place. If template contains one or more of the C-format specifiers
159 %d, %f, %c then line segments will be written to different files;
160 otherwise all lines are written to the specified file (template).
161 The use of the C-format specifiers controls how many files are cre‐
162 ated and how the contours are organized. If the float format %f is
163 present (standard modifications to width and precision are allowed,
164 e.g., %f7.3f), then the filenames will contain the contour value and
165 lines are thus separated into files based on a common contour value.
166 If the integer format %d is present (including modifications like
167 %05d), then all contours are written to individual segment files; if
168 any of the other specifiers are present they just affect the file
169 names. Finally, if the character format %c is present it is replaced
170 with the letters C (for closed) or O (for open), reflecting the
171 nature of each contour. Any combination of one, two, or all three
172 modifiers are valid, resulting in different filenames and number of
173 files. For instance, if %c appears by itself, then only two files
174 are created, separating the open from the closed contours (assuming
175 both kinds are present). If just %f is used, then all segments for
176 the same contour level will be written to the same file, resulting
177 in N multi-segment files. If both %f and %c were combined then each
178 contour level would be further subdivided into closed and open con‐
179 tours. Any combination involving %d will result in one individual
180 file for each segment; %c, %f only modifies the file names. The
181 files are ASCII unless -bo is used.
182 -Eindexfile
184 Give name of file with network information. Each record must
185 contain triplets of node numbers for a triangle [Default com‐
186 putes these using Delaunay triangulation (see triangulate)].
187 -G
189 The required argument controls the placement of labels along the
190 quoted lines. Choose among five controlling algorithms:
191 ddist[c|i|p] or Ddist[d|e|f|k|m|M|n|s]
193 For lower case d, give distances between labels on the plot
194 in your preferred measurement unit c (cm), i (inch), or p
195 (points), while for upper case D, specify distances in map
196 units and append the unit; choose among e (m), f (foot), k
197 (km), M (mile), n (nautical mile) or u (US survey foot), and
198 d (arc degree), m (arc minute), or s (arc second). [Default
199 is 10c or 4i]. As an option, you can append /fraction which
200 is used to place the very first label for each contour when
201 the cumulative along-contour distance equals fraction * dist
202 [0.25].
203 fffile.d
205 Reads the ASCII file ffile.d and places labels at locations
206 in the file that matches locations along the quoted lines.
207 Inexact matches and points outside the region are skipped.
208 l|Lline1[,line2,...]
210 Give start and stop coordinates for one or more comma-sepa‐
211 rated straight line segments. Labels will be placed where
212 these lines intersect the quoted lines. The format of each
213 line specification is start/stop, where start and stop are
214 either a specified point lon/lat or a 2-character XY key that
215 uses the justification format employed in pstext to indicate
216 a point on the map, given as [LCR][BMT]. In addition, you
217 can use Z-, Z+ to mean the global minimum and maximum loca‐
218 tions in the grid. L will interpret the point pairs as defin‐
219 ing great circles [Default is straight line].
220 nn_label
222 Specifies the number of equidistant labels for quoted lines
223 line [1]. Upper case N starts labeling exactly at the start
224 of the line [Default centers them along the line]. N-1 places
225 one justified label at start, while N+1 places one justified
226 label at the end of quoted lines. Optionally, append
227 /min_dist[c|i|p] to enforce that a minimum distance separa‐
228 tion between successive labels is enforced.
229 x|Xxfile.d
231 Reads the multisegment file xfile.d and places labels at the
232 intersections between the quoted lines and the lines in
233 xfile.d. X will resample the lines first along great-circle
234 arcs.
235 In addition, you may optionally append +rradius[c|i|p] to set a min‐
237 imum label separation in the x-y plane [no limitation].
238 -I Color the triangles using the CPT.
240 -Jz|Zparameters (more ...)
242 Set z-axis scaling; same syntax as -Jx.
243 -K (more ...)
245 Do not finalize the PostScript plot.
246 -Lpen (more ...)
248 Draw the underlying triangular mesh using the specified pen
249 attributes [Default is no mesh].
250 -N Do NOT clip contours or image at the boundaries [Default will
252 clip to fit inside region -R].
253 -O (more ...)
255 Append to existing PostScript plot.
256 -P (more ...)
258 Select "Portrait" plot orientation.
259 -Qcut Do not draw contours with less than cut number of points [Draw
261 all contours].
262 -S[p|t]
264 Skip all input xyz points that fall outside the region [Default
265 uses all the data in the triangulation]. Alternatively, use -St
266 to skip triangles whose three vertices are all outside the
267 region. -S with no modifier is interpreted as -Sp.
268 -T[+|-][+dgap[/length]][+l[labels]]
270 Will draw tick marks pointing in the downward direction every
271 gap along the innermost closed contours. Append +dgap and
272 optionally tick mark length (append units as c, i, or p) or use
273 defaults [15p/3p]. User may choose to tick only local highs or
274 local lows by specifying -T+ or -T-, respectively. Append +lla‐
275 bels to annotate the centers of closed innermost contours (i.e.,
276 the local lows and highs). If no labels is appended we use - and
277 + as the labels. Appending exactly two characters, e.g., +lLH,
278 will plot the two characters (here, L and H) as labels. For more
279 elaborate labels, separate the low and hight label strings with
280 a comma (e.g., +llo,hi). If a file is given by -C and -T is set,
281 then only contours marked with upper case C or A will have tick
282 marks [and annotations].
283 -U[[just]/dx/dy/][c|label] (more ...)
285 Draw GMT time stamp logo on plot.
286 -V[level] (more ...)
288 Select verbosity level [c].
289 -W[type]pen[+c[l|f]] (more ...)
291 type, if present, can be a for annotated contours or c for regu‐
292 lar contours [Default]. The pen sets the attributes for the par‐
293 ticular line. Default pen for annotated contours: 0.75p,black.
294 Regular contours use pen 0.25p,black. If the modifier +cl is
295 appended then the color of the contour lines are taken from the
296 CPT (see -C). If instead modifier +cf is appended then the color
297 from the cpt file is applied to the contour annotations. Use
298 just +c for both effects.
299 -X[a|c|f|r][x-shift[u]]
301 -Y[a|c|f|r][y-shift[u]] (more ...)
303 Shift plot origin.
304 -bi[ncols][t] (more ...)
306 Select native binary input. [Default is 3 input columns]. Use
307 4-byte integer triplets for node ids (-E).
308 -bo[ncols][type] (more ...)
310 Select native binary output. [Default is 3 output columns].
311 -d[i|o]nodata (more ...)
313 Replace input columns that equal nodata with NaN and do the
314 reverse on output.
315 -e[~]"pattern" | -e[~]/regexp/[i] (more ...)
317 Only accept data records that match the given pattern.
318 -h[i|o][n][+c][+d][+rremark][+rtitle] (more ...)
320 Skip or produce header record(s).
321 -icols[+l][+sscale][+ooffset][,...] (more ...)
323 Select input columns and transformations (0 is first column).
324 -:[i|o] (more ...)
326 Swap 1st and 2nd column on input and/or output.
327 -p[x|y|z]azim[/elev[/zlevel]][+wlon0/lat0[/z0]][+vx0/y0] (more ...)
329 Select perspective view.
330 -t[transp] (more ...)
332 Set PDF transparency level in percent.
333 -^ or just -
335 Print a short message about the syntax of the command, then
336 exits (NOTE: on Windows just use -).
337 -+ or just +
339 Print an extensive usage (help) message, including the explana‐
340 tion of any module-specific option (but not the GMT common
341 options), then exits.
342 -? or no arguments
344 Print a complete usage (help) message, including the explanation
345 of all options, then exits.
346
348 To make a raw contour plot from the file topo.xyz and drawing the con‐
349 tours (pen = 2) given in the CPT topo.cpt on a Lambert map at 0.5
350 inch/degree along the standard parallels 18 and 24, use
351 gmt pscontour topo.xyz -R320/330/20/30 -Jl18/24/0.5i -Ctopo.cpt -W0.5p > topo.ps
353 To create a color PostScript plot of the numerical temperature solution
355 obtained on a triangular mesh whose node coordinates and temperatures
356 are stored in temp.xyz and mesh arrangement is given by the file
357 mesh.ijk, using the colors in temp.cpt, run
358 gmt pscontour temp.xyz -R0/150/0/100 -Jx0.1i -Ctemp.cpt -G -W0.25p > temp.ps
360 To save the triangulated 100-m contour lines in topo.txt and separate
362 them into multisegment files (one for each contour level), try
363 gmt pscontour topo.txt -C100 -Dcontours_%.0f.txt
365
367 gmt, gmt.conf, gmtcolors, grdcontour, grdimage, nearneighbor,
368 psbasemap, psscale, surface, triangulate
369
371 Watson, D. F., 1982, Acord: Automatic contouring of raw data, Comp. &
372 Geosci., 8, 97-101.
373 Shewchuk, J. R., 1996, Triangle: Engineering a 2D Quality Mesh Genera‐
375 tor and Delaunay Triangulator, First Workshop on Applied Computational
376 Geometry (Philadelphia, PA), 124-133, ACM, May 1996.
377 http://www.cs.cmu.edu/~quake/triangle.html
379
381 2019, P. Wessel, W. H. F. Smith, R. Scharroo, J. Luis, and F. Wobbe
3825.4.5 Feb 24, 2019 PSCONTOUR(1)