1GMT.CONF(5) GMT GMT.CONF(5)
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3
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6 gmt.conf - Configuration for GMT
7
9 The following is a list of the parameters that are user-definable in
10 GMT. The parameter names are always given in UPPER CASE. The parameter
11 values are case-insensitive unless otherwise noted. The system defaults
12 are given in brackets [ for SI (and US) ]. Those marked * can be set on
13 the command line as well (the corresponding option is given in paren‐
14 theses). Note that default distances and lengths below are given in
15 both cm or inch; the chosen default depends on your choice of default
16 unit (see PROJ_LENGTH_UNIT). You can explicitly specify the unit used
17 for distances and lengths by appending c (cm), i (inch), or p (points).
18 When no unit is indicated the value will be assumed to be in the unit
19 set by PROJ_LENGTH_UNIT. Several parameters take only true or false.
20 Finally, most of these parameters can be changed on-the-fly via the
21 --PARAMETER=VALUE option to any GMT program. However, a few are static
22 and are only read via the gmt.conf file; these are labeled (static).
23
25 The full explanation for how to specify pens, pattern fills, colors,
26 and fonts can be found in the gmt man page.
27
28 ┌───────────────────────────┬─────────┐
29 │THEMATIC SUB-SECTIONS │ prefix │
30 ├───────────────────────────┼─────────┤
31 │COLOR Parameters │ COLOR_ │
32 ├───────────────────────────┼─────────┤
33 │DIR Parameters │ DIR_ │
34 ├───────────────────────────┼─────────┤
35 │FONT Parameters │ FONT_ │
36 ├───────────────────────────┼─────────┤
37 │FORMAT Parameters │ FORMAT_ │
38 ├───────────────────────────┼─────────┤
39 │GMT Miscellaneous Parame‐ │ GMT_ │
40 │ters │ │
41 ├───────────────────────────┼─────────┤
42 │I/O Parameters │ IO_ │
43 ├───────────────────────────┼─────────┤
44 │MAP Parameters │ MAP_ │
45 ├───────────────────────────┼─────────┤
46 │Projection Parameters │ PROJ_ │
47 ├───────────────────────────┼─────────┤
48 │PostScript Parameters │ PS_ │
49 ├───────────────────────────┼─────────┤
50 │Calendar/Time Parameters │ TIME_ │
51 └───────────────────────────┴─────────┘
52
53 COLOR_BACKGROUND
54 Color used for the background of images (i.e., when z < lowest
55 color table entry) [black].
56
57 COLOR_FOREGROUND
58 Color used for the foreground of images (i.e., when z > highest
59 color table entry) [white].
60
61 COLOR_HSV_MAX_S
62 Maximum saturation (0-1) assigned for most positive intensity
63 value [0.1].
64
65 COLOR_HSV_MIN_S
66 Minimum saturation (0-1) assigned for most negative intensity
67 value [1.0].
68
69 COLOR_HSV_MAX_V
70 Maximum value (0-1) assigned for most positive intensity value
71 [1.0].
72
73 COLOR_HSV_MIN_V
74 Minimum value (0-1) assigned for most negative intensity value
75 [0.3].
76
77 COLOR_MODEL
78 Selects in which color space a CPT should be interpolated. By
79 default, color interpolation takes place directly on the RGB
80 values which can produce some unexpected hues, whereas interpo‐
81 lation directly on the HSV values better preserves those hues.
82 The choices are: none (default: use whatever the COLOR_MODEL
83 setting in the CPT demands), rgb (force interpolation in RGB),
84 hsv (force interpolation in HSV), cmyk (assumes colors are in
85 CMYK but interpolates in RGB).
86
87 COLOR_NAN
88 Color used for the non-defined areas of images (i.e., where z ==
89 NaN) [127.5].
90
91 DIR_CACHE
92 Cache directory where to save files downloaded when using exter‐
93 nal URL addresses or the files called earth_relief_res.grd or
94 filenames starting in @ (e.g., @hotspots.txt)
95
96 DIR_DATA
97 Session data dir. Overrides the value of the environment vari‐
98 able $GMT_DATADIR (see Directory parameters in the CookBook).
99
100 DIR_DCW
101 Path to optional Digital Chart of the World polygon files.
102
103 DIR_GSHHG
104 Path to GSHHG files. Defaults to $GMT_SHAREDIR/coast if empty.
105
106 FONT Sets the default for all fonts, except FONT_LOGO. This setting
107 is not included in the gmt.conf file.
108
109 FONT_ANNOT
110 Sets both FONT_ANNOT_PRIMARY and FONT_ANNOT_SECONDARY to the
111 value specified. This setting is not included in the gmt.conf
112 file.
113
114 FONT_ANNOT_PRIMARY
115 Font used for primary annotations, etc. [12p,Helvetica,black].
116 When + is prepended, scale fonts, offsets and tick-lengths rela‐
117 tive to FONT_ANNOT_PRIMARY.
118
119 FONT_ANNOT_SECONDARY
120 Font to use for time axis secondary annotations [14p,Hel‐
121 vetica,black].
122
123 FONT_LABEL
124 Font to use when plotting labels below axes [16p,Hel‐
125 vetica,black].
126
127 FONT_LOGO
128 Font to use for text plotted as part of the GMT time logo
129 [8p,Helvetica,black].
130
131 FONT_TITLE
132 Font to use when plotting titles over graphs [24p,Hel‐
133 vetica,black].
134
135 FORMAT_CLOCK_IN
136 Formatting template that indicates how an input clock string is
137 formatted. This template is then used to guide the reading of
138 clock strings in data fields. To properly decode 12-hour clocks,
139 append am or pm (or upper case) to match your data records. As
140 examples, try hh:mm, hh:mm:ssAM, etc. [hh:mm:ss].
141
142 FORMAT_CLOCK_MAP
143 Formatting template that indicates how an output clock string is
144 to be plotted. This template is then used to guide the format‐
145 ting of clock strings in plot annotations. See FORMAT_CLOCK_OUT
146 for details. [hh:mm:ss].
147
148 FORMAT_CLOCK_OUT
149 Formatting template that indicates how an output clock string is
150 to be formatted. This template is then used to guide the writing
151 of clock strings in data fields. To use a floating point format
152 for the smallest unit (e.g., seconds), append .xxx, where the
153 number of x indicates the desired precision. If no floating
154 point is indicated then the smallest specified unit will be
155 rounded off to nearest integer. For 12-hour clocks, append am,
156 AM, a.m., or A.M. (GMT will replace a|A with p|P for pm). If
157 your template starts with a leading hyphen (-) then each integer
158 item (y,m,d) will be printed without leading zeros (default uses
159 fixed width formats). As examples, try hh:mm, hh.mm.ss,
160 hh:mm:ss.xxxx, hha.m., etc. [hh:mm:ss]. If the format is simply
161 - then no clock is output and the ISO T divider between date and
162 clock is omitted.
163
164 FORMAT_DATE_IN
165 Formatting template that indicates how an input date string is
166 formatted. This template is then used to guide the reading of
167 date strings in data fields. You may specify either Gregorian
168 calendar format or ISO week calendar format. Gregorian calendar:
169 Use any combination of yyyy (or yy for 2-digit years; if so see
170 TIME_Y2K_OFFSET_YEAR), mm (or o for abbreviated month name in
171 the current time language), and dd, with or without delimiters.
172 For day-of-year data, use jjj instead of mm and/or dd. Examples
173 can be ddmmyyyy, yy-mm-dd, dd-o-yyyy, yyyy/dd/mm, yyyy-jjj, etc.
174 ISO Calendar: Expected template is yyyy[-]W[-]ww[-]d, where ww
175 is ISO week and d is ISO week day. Either template must be con‐
176 sistent, e.g., you cannot specify months if you do not specify
177 years. Examples are yyyyWwwd, yyyy-Www, etc. [yyyy-mm-dd].
178
179 FORMAT_DATE_MAP
180 Formatting template that indicates how an output date string is
181 to be plotted. This template is then used to guide the plotting
182 of date strings in data fields. See FORMAT_DATE_OUT for details.
183 In addition, you may use a single o instead of mm (to plot month
184 name) and u instead of W[-]ww to plot "Week ##". Both of these
185 text strings will be affected by the GMT_LANGUAGE, FOR‐
186 MAT_TIME_PRIMARY_MAP and FORMAT_TIME_SECONDARY_MAP setting.
187 [yyyy-mm-dd].
188
189 FORMAT_DATE_OUT
190 Formatting template that indicates how an output date string is
191 to be formatted. This template is then used to guide the writing
192 of date strings in data fields. You may specify either Gregorian
193 calendar format or ISO week calendar format. Gregorian calendar:
194 Use any combination of yyyy (or yy for 2-digit years; if so see
195 TIME_Y2K_OFFSET_YEAR), mm (or o for abbreviated month name in
196 the current time language), and dd, with or without delimiters.
197 For day-of-year data, use jjj instead of mm and/or dd. As exam‐
198 ples, try yy/mm/dd, yyyy=jjj, dd-o-yyyy, dd-mm-yy, yy-mm, etc.
199 ISO Calendar: Expected template is yyyy[-]W[-]ww[-]d, where ww
200 is ISO week and d is ISO week day. Either template must be con‐
201 sistent, e.g., you cannot specify months if you do not specify
202 years. As examples, try yyyyWww, yy-W-ww-d, etc. If your tem‐
203 plate starts with a leading hyphen (-) then each integer item
204 (y,m,d) will be printed without leading zeros (default uses
205 fixed width formats) [yyyy-mm-dd]. If the format is simply -
206 then no date is output and the ISO T divider between date and
207 clock is omitted.
208
209 FORMAT_GEO_MAP
210 Formatting template that indicates how an output geographical
211 coordinate is to be plotted. This template is then used to guide
212 the plotting of geographical coordinates in data fields. See
213 FORMAT_GEO_OUT for details. In addition, you can append A which
214 plots the absolute value of the coordinate. The default is
215 ddd:mm:ss. Not all items may be plotted as this depends on the
216 annotation interval.
217
218 FORMAT_GEO_OUT
219 Formatting template that indicates how an output geographical
220 coordinate is to be formatted. This template is then used to
221 guide the writing of geographical coordinates in data fields.
222 The template is in general of the form [+|-]D or
223 [+|-]ddd[:mm[:ss]][.xxx][F]. By default, longitudes will be
224 reported in the range [-180,180]. The various terms have the
225 following purpose:
226
227 +D Output longitude in the range [0,360]
228
229 -D Output longitude in the range [-360,0]
230
231 D Use FORMAT_FLOAT_OUT for floating point degrees.
232
233 ddd Fixed format integer degrees
234
235 : delimiter used
236
237 mm Fixed format integer arc minutes
238
239 ss Fixed format integer arc seconds
240
241 .xxx Floating fraction of previous integer field, fixed width.
242
243 F Encode sign using WESN suffix
244
245 G Same as F but with a leading space before suffix
246
247 The default is D.
248
249 FORMAT_FLOAT_MAP
250 Format (C language printf syntax) to be used when plotting dou‐
251 ble precision floating point numbers along plot frames and con‐
252 tours. For geographic coordinates, see FORMAT_GEO_MAP.
253 [%.12lg].
254
255 FORMAT_FLOAT_OUT
256 Format (C language printf syntax) to be used when printing dou‐
257 ble precision floating point numbers to output files. For geo‐
258 graphic coordinates, see FORMAT_GEO_OUT. [%.12lg]. To give some
259 columns a separate format, supply one or more comma-separated
260 cols:format specifications, where cols can be specific columns
261 (e.g., 5 for 6th since 0 is the first) or a range of columns
262 (e.g., 3-7). The last specification without column information
263 will override the format for all other columns. Alternatively,
264 you can list N space-separated formats and these apply to the
265 first N columns.
266
267 FORMAT_TIME_MAP
268 Sets both FORMAT_TIME_PRIMARY_MAP and FORMAT_TIME_SECONDARY_MAP
269 to the value specified. This setting is not included in the
270 gmt.conf file.
271
272 FORMAT_TIME_PRIMARY_MAP
273 Controls how primary month-, week-, and weekday-names are for‐
274 matted. Choose among full, abbreviated, and character. If the
275 leading f, a, or c are replaced with F, A, and C the entire
276 annotation will be in upper case [full].
277
278 FORMAT_TIME_SECONDARY_MAP
279 Controls how secondary month-, week-, and weekday-names are for‐
280 matted. Choose among full, abbreviated, and character. If the
281 leading f, a, or c are replaced with F, A, and C the entire
282 annotation will be in upper case [full].
283
284 FORMAT_TIME_STAMP
285 Defines the format of the time information in the UNIX time
286 stamp. This format is parsed by the C function strftime, so
287 that virtually any text can be used (even not containing any
288 time information) [%Y %b %d %H:%M:%S].
289
290 GMT_COMPATIBILITY
291 Determines if this GMT version should be able to parse com‐
292 mand-line options for a prior major release. Specify either 4
293 or 5. If 4 is set we will parse obsolete GMT 4 options and issue
294 warnings; if 5 is set then parsing GMT 4 only syntax will result
295 in errors [4].
296
297 GMT_EXPORT_TYPE
298 This setting is only used by external interfaces and controls
299 the data type used for table entries. Choose from double, sin‐
300 gle, [u]long, [u]int, [u]short, and [u]char [double].
301
302 GMT_EXTRAPOLATE_VAL
303 Determines what to do if extrapolating beyond the data domain.
304 Choose among 'NaN', 'extrap' or 'extrapval,val' (without
305 quotes). In the first case return NaN for any element of x that
306 is outside range [Default]. Second case lets the selected algo‐
307 rithm compute the extrapolation values. Third case sets the
308 extrapolation values to the constant value passed in 'val' (this
309 value must off course be numeric).
310
311 GMT_CUSTOM_LIBS
312 Comma-separated list of GMT-compliant shared libraries that
313 extend the capability of GMT with additional custom modules
314 [none]. Alternatively, provide a directory name, that MUST end
315 with a slash (or back slash), to use all shared libraries in
316 that directory. On Windows, if the dir name is made up only of a
317 single slash ('/') search inside a subdirectory called
318 'gmt_plugins' of the directory that contains the 'gmt' exe‐
319 cutable. See the API documentation for how to build your own
320 shared modules.
321
322 GMT_FFT
323 Determines which Fast Fourier Transform (FFT) should be used
324 among those that have been configured during installation.
325 Choose from auto (pick the most suitable for the task among
326 available algorithms), fftw[,planner_flag] (The Fastest Fourier
327 Transform in the West), accelerate (Use the Accelerate Framework
328 under OS X; Note, that the number of samples to be processed
329 must be a base 2 exponent), kiss, (Kiss FFT), brenner Brenner
330 Legacy FFT [auto]. FFTW can "learn" how to optimally compute
331 Fourier transforms on the current hardware and OS by computing
332 several FFTs and measuring their execution time. This so gained
333 "Wisdom" will be stored in and reloaded from the file fftw_wis‐
334 dom_<hostname> in $GMT_USERDIR or, if $GMT_USERDIR is not
335 writable, in the current directory. To use this feature append
336 planner_flag, which can be one of measure, patient, and exhaus‐
337 tive; see FFTW reference for details. The default FFTW planner
338 flag is estimate, i.e., pick a (probably sub-optimal) plan
339 quickly. Note: if you need a single transform of a given size
340 only, the one-time cost of the smart planner becomes signifi‐
341 cant. In that case, stick to the default planner, estimate,
342 based on heuristics.
343
344 GMT_HISTORY
345 Passes the history of past common command options via the
346 gmt.history file. The different values for this setting are:
347 true, readonly, false, to either read and write to the gmt.his‐
348 tory file, only read, or not use the file at all [true].
349
350 GMT_INTERPOLANT
351 Determines if linear (linear), Akima's spline (akima), natural
352 cubic spline (cubic) or no interpolation (none) should be used
353 for 1-D interpolations in various programs [akima].
354
355 GMT_LANGUAGE
356 Language to use when plotting calendar and map items such as
357 months and days, map annotations and cardinal points. Select
358 from:
359
360 · CN1 Simplified Chinese
361
362 · CN2 Traditional Chinese
363
364 · DE German
365
366 · DK Danish
367
368 · EH Basque
369
370 · ES Spanish
371
372 · FI Finnish
373
374 · FR French
375
376 · GR Greek
377
378 · HI Hawaiian
379
380 · HU Hungarian
381
382 · IE Irish
383
384 · IL Hebrew
385
386 · IS Icelandic
387
388 · IT Italian
389
390 · JP Japanese
391
392 · KR Korean
393
394 · NL Dutch
395
396 · NO Norwegian
397
398 · PL Polish
399
400 · PT Portuguese
401
402 · RU Russian
403
404 · SE Swedish
405
406 · SG Scottish Gaelic
407
408 · TO Tongan
409
410 · TR Turkish
411
412 · UK British English
413
414 · US US English
415
416 If your language is not supported, please examine the
417 $GMT_SHAREDIR/localization/gmt_us.locale file and make a similar
418 file. Please submit it to the GMT Developers for official inclu‐
419 sion. Custom language files can be placed in directories
420 $GMT_SHAREDIR/localization or ~/.gmt. Note: Some of these lan‐
421 guages may require you to also change the PS_CHAR_ENCODING set‐
422 ting.
423
424 GMT_TRIANGULATE
425 Determines if we use the Watson [Default] or Shewchuk algorithm
426 (if configured during installation) for triangulation. Note
427 that Shewchuk is required for operations involving Voronoi con‐
428 structions.
429
430 GMT_VERBOSE
431 (-V) Determines the level of verbosity used by GMT programs.
432 Choose among 6 levels; each level adds to the verbosity of the
433 lower levels: quiet, nnormal (errors and warnings), compatibil‐
434 ity warnings, verbose progress reports, long verbose progress
435 reports, debugging messages [c].
436
437 IO_COL_SEPARATOR
438 This setting determines what character will separate ASCII out‐
439 put data columns written by GMT. Choose from tab, space, comma,
440 and none [tab].
441
442 IO_GRIDFILE_FORMAT
443 Default file format for grids, with optional scale, offset and
444 invalid value, written as ff[+sscale][+ooffset][+ninvalid]. The
445 2-letter format indicator can be one of [abcegnrs][bsifd]. See
446 grdconvert and Section grid-file-format of the GMT Technical
447 Reference and Cookbook for more information. You may the scale
448 as a for auto-adjusting the scale and/or offset of packed inte‐
449 ger grids (=ID+sa is a shorthand for =ID+sa+oa). When invalid
450 is omitted the appropriate value for the given format is used
451 (NaN or largest negative). [nf].
452
453 IO_GRIDFILE_SHORTHAND
454 If true, all grid file names are examined to see if they use the
455 file extension shorthand discussed in Section grid-file-format
456 of the GMT Technical Reference and Cookbook. If false, no file‐
457 name expansion is done [false].
458
459 IO_HEADER
460 (-h) Specifies whether input/output ASCII files have header
461 record(s) or not [false].
462
463 IO_LONLAT_TOGGLE
464 (-:) Set if the first two columns of input and output files con‐
465 tain (latitude,longitude) or (y,x) rather than the expected
466 (longitude,latitude) or (x,y). false means we have (x,y) both on
467 input and output. true means both input and output should be
468 (y,x). IN means only input has (y,x), while OUT means only out‐
469 put should be (y,x). [false].
470
471 IO_N_HEADER_RECS
472 Specifies how many header records to expect if -h is used [0].
473 Note: This will skip the specified number of records regardless
474 of what they are. Since any records starting with # is automat‐
475 ically considered a header you will only specify a non-zero num‐
476 ber in order to skip headers that do not conform to that conven‐
477 tion.
478
479 IO_NAN_RECORDS
480 Determines what happens when input records containing NaNs for x
481 or y (and in some cases z) are read. Choose between skip, which
482 will simply report how many bad records were skipped, and pass
483 [Default], which will pass these records on to the calling pro‐
484 grams. For most programs this will result in output records with
485 NaNs as well, but some will interpret these NaN records to indi‐
486 cate gaps in a series; programs may then use that information to
487 detect segmentation (if applicable).
488
489 IO_NC4_CHUNK_SIZE
490 Sets the default chunk size for the lat and lon dimension of the
491 z variable. Very large chunk sizes and sizes smaller than 128
492 should be avoided because they can lead to unexpectedly bad per‐
493 formance. Note that a chunk of a single precision floating point
494 variable of size 2896x2896 completely fills the chunk cache of
495 32MiB. Specify the chunk size for each dimension separated by a
496 comma, or auto for optimally chosen chunk sizes in the range
497 [128,256). Setting IO_NC4_CHUNK_SIZE will produce netCDF version
498 4 files, which can only be read with the netCDF 4 library,
499 unless all dimensions are less than 128 or classic is specified
500 for classic netCDF. [auto]
501
502 IO_NC4_DEFLATION_LEVEL
503 Sets the compression level for netCDF4 files upon output. Values
504 allowed are integers from 0 (no compression) to 9 (maximum com‐
505 pression). Enabling a low compression level can dramatically
506 improve performance and reduce the size of certain data. While
507 higher compression levels further reduce the data size, they do
508 so at the cost of extra processing time. This parameter does not
509 apply to classic netCDF files. [3]
510
511 IO_SEGMENT_BINARY
512 Determines how binary data records with all values set to NaN
513 are interpreted. Such records are considered to be encoded seg‐
514 ment headers in binary files provided the number of columns
515 equals or exceeds the current setting of IO_SEGMENT_BINARY [2].
516 Specify 0 or "off" to deactivate the segment header determina‐
517 tion.
518
519 IO_SEGMENT_MARKER
520 This holds the character we expect to indicate a segment header
521 in an incoming ASCII data or text table [>]. If this marker
522 should be different for output then append another character for
523 the output segment marker. The two characters must be separated
524 by a comma. Two marker characters have special meaning: B means
525 "blank line" and will treat blank lines as initiating a new seg‐
526 ment, whereas N means "NaN record" and will treat records with
527 all NaNs as initiating a new segment. If you choose B or N for
528 the output marker then the normal GMT segment header is replaced
529 by a blank or NaN record, respectively, and no segment header
530 information is written. To use B or N as regular segment markers
531 you must escape them with a leading backslash.
532
533 MAP_ANNOT_MIN_ANGLE
534 If the angle between the map boundary and the annotation base‐
535 line is less than this minimum value (in degrees), the annota‐
536 tion is not plotted (this may occur for certain oblique projec‐
537 tions.) Give a value in the range [0,90]. [20]
538
539 MAP_ANNOT_MIN_SPACING
540 If an annotation would be plotted less than this minimum dis‐
541 tance from its closest neighbor, the annotation is not plotted
542 (this may occur for certain oblique projections.) [0p]
543
544 MAP_ANNOT_OBLIQUE
545 This integer is a sum of 6 bit flags (most of which only are
546 relevant for oblique projections): If bit 1 is set (1), annota‐
547 tions will occur wherever a gridline crosses the map boundaries,
548 else longitudes will be annotated on the lower and upper bound‐
549 aries only, and latitudes will be annotated on the left and
550 right boundaries only. If bit 2 is set (2), then longitude anno‐
551 tations will be plotted horizontally. If bit 3 is set (4), then
552 latitude annotations will be plotted horizontally. If bit 4 is
553 set (8), then oblique tick-marks are extended to give a projec‐
554 tion equal to the specified tick length. If bit 5 is set (16),
555 tick-marks will be drawn normal to the border regardless of
556 gridline angle. If bit 6 is set (32), then latitude annotations
557 will be plotted parallel to the border. To set a combination of
558 these, add up the values in parentheses. [1].
559
560 MAP_ANNOT_OFFSET
561 Sets both MAP_ANNOT_OFFSET_PRIMARY and MAP_ANNOT_OFFSET_SEC‐
562 ONDARY to the value specified. This setting is not included in
563 the gmt.conf file.
564
565 MAP_ANNOT_OFFSET_PRIMARY
566 Distance from end of tick-mark to start of annotation [5p].
567
568 MAP_ANNOT_OFFSET_SECONDARY
569 Distance from base of primary annotation to the top of the sec‐
570 ondary annotation [5p] (Only applies to time axes with both pri‐
571 mary and secondary annotations).
572
573 MAP_ANNOT_ORTHO
574 Determines which axes will get their annotations (for linear
575 projections) plotted orthogonally to the axes. Combine any w, e,
576 s, n, z (uppercase allowed as well). [we] (if nothing speci‐
577 fied).
578
579 MAP_DEFAULT_PEN
580 Sets the default of all pens related to -W options. Prepend + to
581 overrule the color of the parameters MAP_GRID_PEN_PRIMARY,
582 MAP_GRID_PEN_SECONDARY, MAP_FRAME_PEN, MAP_TICK_PEN_PRIMARY, and
583 MAP_TICK_PEN_SECONDARY by the color of MAP_DEFAULT_PEN
584 [default,black].
585
586 MAP_DEGREE_SYMBOL
587 Determines what symbol is used to plot the degree symbol on geo‐
588 graphic map annotations. Choose between ring, degree, colon, or
589 none [ring].
590
591 MAP_FRAME_AXES
592 Sets which axes to draw and annotate. Combine any uppercase W,
593 E, S, N, Z to draw and annotate west, east, south, north and/or
594 vertical (perspective view only) axis. Use lower case to draw
595 the axis only, but not annotate. Add an optional + to draw a
596 cube of axes in perspective view. [WESN].
597
598 MAP_FRAME_PEN
599 Pen attributes used to draw plain map frame [thicker,black].
600
601 MAP_FRAME_TYPE
602 Choose between inside, plain and fancy (thick boundary, alter‐
603 nating black/white frame; append + for rounded corners) [fancy].
604 For some map projections (e.g., Oblique Mercator), plain is the
605 only option even if fancy is set as default. In general, fancy
606 only applies to situations where the projected x and y direc‐
607 tions parallel the longitude and latitude directions (e.g., rec‐
608 tangular projections, polar projections). For situations where
609 all boundary ticks and annotations must be inside the maps
610 (e.g., for preparing geotiffs), chose inside. Finally, for
611 Cartesian plots you can also choose graph, which adds a vector
612 to the end of each axis. This works best when you reduce the
613 number of axes plotted.
614
615 MAP_FRAME_WIDTH
616 Width (> 0) of map borders for fancy map frame [5p].
617
618 MAP_GRID_CROSS_SIZE
619 Sets both MAP_GRID_CROSS_SIZE_PRIMARY and
620 MAP_GRID_CROSS_SIZE_SECONDARY to the value specified. This set‐
621 ting is not included in the gmt.conf file.
622
623 MAP_GRID_CROSS_SIZE_PRIMARY
624 Size (>= 0) of grid cross at lon-lat intersections. 0 means draw
625 continuous gridlines instead [0p].
626
627 MAP_GRID_CROSS_SIZE_SECONDARY
628 Size (>= 0) of grid cross at secondary lon-lat intersections. 0
629 means draw continuous gridlines instead [0p].
630
631 MAP_GRID_CROSS_PEN
632 Sets both MAP_GRID_CROSS_PEN_PRIMARY and MAP_GRID_CROSS_PEN_SEC‐
633 ONDARY to the value specified. This setting is not included in
634 the gmt.conf file.
635
636 MAP_GRID_PEN_PRIMARY
637 Pen attributes used to draw primary grid lines in dpi units or
638 points (append p) [default,black].
639
640 MAP_GRID_PEN_SECONDARY
641 Pen attributes used to draw secondary grid lines in dpi units or
642 points (append p) [thinner,black].
643
644 MAP_LABEL_OFFSET
645 Distance from base of axis annotations to the top of the axis
646 label [8p].
647
648 MAP_LINE_STEP
649 Determines the maximum length (> 0) of individual straight
650 line-segments when drawing arcuate lines [0.75p]
651
652 MAP_LOGO
653 (-U) Specifies if a GMT logo with system timestamp should be
654 plotted at the lower left corner of the plot [false].
655
656 MAP_LOGO_POS
657 (-U) Sets the justification and the position of the logo/time‐
658 stamp box relative to the current plots lower left corner of the
659 plot [BL/-54p/-54p].
660
661 MAP_ORIGIN_X
662 (-X) Sets the x-coordinate of the origin on the paper for a new
663 plot [1i]. For an overlay, the default offset is 0.
664
665 MAP_ORIGIN_Y
666 (-Y) Sets the y-coordinate of the origin on the paper for a new
667 plot [1i]. For an overlay, the default offset is 0.
668
669 MAP_POLAR_CAP
670 Controls the appearance of gridlines near the poles for all
671 azimuthal projections and a few others in which the geographic
672 poles are plotted as points (Lambert Conic, Oblique Mercator,
673 Hammer, Mollweide, Sinusoidal and van der Grinten). Specify
674 either none (in which case there is no special handling) or
675 pc_lat/pc_dlon. In that case, normal gridlines are only drawn
676 between the latitudes -pc_lat/+*pc_lat*, and above those lati‐
677 tudes the gridlines are spaced at the (presumably coarser)
678 pc_dlon interval; the two domains are separated by a small cir‐
679 cle drawn at the pc_lat latitude [85/90]. Note for r-theta
680 (polar) projection where r = 0 is at the center of the plot the
681 meaning of the cap is reversed, i.e., the default 85/90 will
682 draw a r = 5 radius circle at the center of the map with less
683 frequent radial lines there.
684
685 MAP_SCALE_HEIGHT
686 Sets the height (> 0) on the map of the map scale bars drawn by
687 various programs [5p].
688
689 MAP_TICK_LENGTH
690 Sets both MAP_TICK_LENGTH_PRIMARY and MAP_TICK_LENGTH_SECONDARY
691 to the value specified. This setting is not included in the
692 gmt.conf file.
693
694 MAP_TICK_LENGTH_PRIMARY
695 The length of a primary major/minor tick-marks [5p/2.5p]. If
696 only the first value is set, the second is assumed to be 50% of
697 the first.
698
699 MAP_TICK_LENGTH_SECONDARY
700 The length of a secondary major/minor tick-marks [15p/3.75p]. If
701 only the first value is set, the second is assumed to be 25% of
702 the first.
703
704 MAP_TICK_PEN
705 Sets both MAP_TICK_PEN_PRIMARY and MAP_TICK_PEN_SECONDARY to the
706 value specified. This setting is not included in the gmt.conf
707 file.
708
709 MAP_TICK_PEN_PRIMARY
710 Pen attributes to be used for primary tick-marks in dpi units or
711 points (append p) [thinner,black].
712
713 MAP_TICK_PEN_SECONDARY
714 Pen attributes to be used for secondary tick-marks in dpi units
715 or points (append p) [thinner,black].
716
717 MAP_TITLE_OFFSET
718 Distance from top of axis annotations (or axis label, if
719 present) to base of plot title [14p].
720
721 MAP_VECTOR_SHAPE
722 Determines the shape of the head of a vector. Normally (i.e.,
723 for vector_shape = 0), the head will be triangular, but can be
724 changed to an arrow (1) or an open V (2). Intermediate settings
725 give something in between. Negative values (up to -2) are
726 allowed as well [0].
727
728 PROJ_AUX_LATITUDE
729 Only applies when geodesics are approximated by great circle
730 distances on an equivalent sphere. Select from authalic, geocen‐
731 tric, conformal, meridional, parametric, or none [authalic].
732 When not none we convert any latitude used in the great circle
733 calculation to the chosen auxiliary latitude before doing the
734 distance calculation. See also PROJ_MEAN_RADIUS.
735
736 PROJ_ELLIPSOID
737 The (case sensitive) name of the ellipsoid used for the map pro‐
738 jections [WGS-84]. Choose among:
739
740 Airy: Applies to Great Britain (1830)
741 Airy-Ireland: Applies to Ireland in 1965 (1830)
742 Andrae: Applies to Denmark and Iceland (1876)
743 APL4.9: Appl. Physics (1965)
744 ATS77: Average Terrestrial System, Canada Maritime provinces (1977)
745 Australian: Applies to Australia (1965)
746 Bessel: Applies to Central Europe, Chile, Indonesia (1841)
747 Bessel-Namibia: Same as Bessel-Schwazeck (1841)
748 Bessel-NGO1948: Modified Bessel for NGO 1948 (1841)
749 Bessel-Schwazeck: Applies to Namibia (1841)
750 Clarke-1858: Clarke's early ellipsoid (1858)
751 Clarke-1866: Applies to North America, the Philippines (1866)
752 Clarke-1866-Michigan: Modified Clarke-1866 for Michigan (1866)
753 Clarke-1880: Applies to most of Africa, France (1880)
754 Clarke-1880-Arc1950: Modified Clarke-1880 for Arc 1950 (1880)
755 Clarke-1880-IGN: Modified Clarke-1880 for IGN (1880)
756 Clarke-1880-Jamaica: Modified Clarke-1880 for Jamaica (1880)
757 Clarke-1880-Merchich: Modified Clarke-1880 for Merchich (1880)
758 Clarke-1880-Palestine: Modified Clarke-1880 for Palestine (1880)
759 CPM: Comm. des Poids et Mesures, France (1799)
760 Delambre: Applies to Belgium (1810)
761 Engelis: Goddard Earth Models (1985)
762 Everest-1830: India, Burma, Pakistan, Afghanistan, Thailand (1830)
763 Everest-1830-Kalianpur: Modified Everest for Kalianpur (1956) (1830)
764 Everest-1830-Kertau: Modified Everest for Kertau, Malaysia & Singapore (1830)
765 Everest-1830-Pakistan: Modified Everest for Pakistan (1830)
766 Everest-1830-Timbalai: Modified Everest for Timbalai, Sabah Sarawak (1830)
767 Fischer-1960: Used by NASA for Mercury program (1960)
768 Fischer-1960-SouthAsia: Same as Modified-Fischer-1960 (1960)
769 Fischer-1968: Used by NASA for Mercury program (1968)
770 FlatEarth: As Sphere, but implies fast "Flat Earth" distance calculations (1984)
771 GRS-67: International Geodetic Reference System (1967)
772 GRS-80: International Geodetic Reference System (1980)
773 Hayford-1909: Same as the International 1924 (1909)
774 Helmert-1906: Applies to Egypt (1906)
775 Hough: Applies to the Marshall Islands (1960)
776 Hughes-1980: Hughes Aircraft Company for DMSP SSM/I grid products (1980)
777 IAG-75: International Association of Geodesy (1975)
778 Indonesian: Applies to Indonesia (1974)
779 International-1924: Worldwide use (1924)
780 International-1967: Worldwide use (1967)
781 Kaula: From satellite tracking (1961)
782 Krassovsky: Used in the (now former) Soviet Union (1940)
783 Lerch: For geoid modeling (1979)
784 Maupertius: Really old ellipsoid used in France (1738)
785 Mercury-1960: Same as Fischer-1960 (1960)
786 MERIT-83: United States Naval Observatory (1983)
787 Modified-Airy: Same as Airy-Ireland (1830)
788 Modified-Fischer-1960: Applies to Singapore (1960)
789 Modified-Mercury-1968: Same as Fischer-1968 (1968)
790 NWL-10D: Naval Weapons Lab (Same as WGS-72) (1972)
791 NWL-9D: Naval Weapons Lab (Same as WGS-66) (1966)
792 OSU86F: Ohio State University (1986)
793 OSU91A: Ohio State University (1991)
794 Plessis: Old ellipsoid used in France (1817)
795 SGS-85: Soviet Geodetic System (1985)
796 South-American: Applies to South America (1969)
797 Sphere: The mean radius in WGS-84 (for spherical/plate tectonics applications) (1984)
798 Struve: Friedrich Georg Wilhelm Struve (1860)
799 TOPEX: Used commonly for altimetry (1990)
800 Walbeck: First least squares solution by Finnish astronomer (1819)
801 War-Office: Developed by G. T. McCaw (1926)
802 WGS-60: World Geodetic System (1960)
803 WGS-66: World Geodetic System (1966)
804 WGS-72: World Geodetic System (1972)
805 WGS-84: World Geodetic System [Default] (1984)
806 Moon: Moon (IAU2000) (2000)
807 Mercury: Mercury (IAU2000) (2000)
808 Venus: Venus (IAU2000) (2000)
809 Mars: Mars (IAU2000) (2000)
810 Jupiter: Jupiter (IAU2000) (2000)
811 Saturn: Saturn (IAU2000) (2000)
812 Uranus: Uranus (IAU2000) (2000)
813 Neptune: Neptune (IAU2000) (2000)
814 Pluto: Pluto (IAU2000) (2000)
815
816 Note that for some global projections, GMT may use a spherical
817 approximation of the ellipsoid chosen, setting the flattening to
818 zero, and using a mean radius. A warning will be given when this
819 happens. If a different ellipsoid name than those mentioned here is
820 given, GMT will attempt to parse the name to extract the semi-major
821 axis (a in m) and the flattening. Formats allowed are:
822
823 a implies a zero flattening
824
825 a,inv_f where inv_f is the inverse flattening
826
827 a,b=b where b is the semi-minor axis (in m)
828
829 a,f=f where f is the flattening
830
831 This way a custom ellipsoid (e.g., those used for other planets) may
832 be used. Further note that coordinate transformations in mapproject
833 can also specify specific datums; see the mapproject man page for
834 further details and how to view ellipsoid and datum parameters.
835
836 PROJ_GEODESIC
837 Selects the algorithm to use for geodesic calculations. Choose
838 between Vincenty [Default], Rudoe, or Andoyer. The Andoyer algo‐
839 rithm is only approximate (to within a few tens of meters) but
840 is up to 5 times faster. The Rudoe is given for legacy pur‐
841 poses. The default Vincenty is accurate to about 0.5 mm.
842
843 PROJ_LENGTH_UNIT
844 Sets the unit length. Choose between cm, inch, or point [c (or
845 i)]. Note that, in GMT, one point is defined as 1/72 inch (the
846 PostScript definition), while it is often defined as 1/72.27
847 inch in the typesetting industry. There is no universal defini‐
848 tion.
849
850 PROJ_MEAN_RADIUS
851 Applies when geodesics are approximated by great circle dis‐
852 tances on an equivalent sphere or when surface areas are com‐
853 puted. Select from mean (R_1), authalic (R_2), volumetric (R_3),
854 meridional, or quadratic [authalic].
855
856 PROJ_SCALE_FACTOR
857 Changes the default map scale factor used for the Polar Stereo‐
858 graphic [0.9996], UTM [0.9996], and Transverse Mercator [1] pro‐
859 jections in order to minimize areal distortion. Provide a new
860 scale-factor or leave as default.
861
862 PS_CHAR_ENCODING
863 (static) Names the eight bit character set being used for text
864 in files and in command line parameters. This allows GMT to
865 ensure that the PostScript output generates the correct charac‐
866 ters on the plot.. Choose from Standard, Standard+, ISOLatin1,
867 ISOLatin1+, and ISO-8859-x (where x is in the ranges [1,10] or
868 [13,15]). See Appendix F for details [ISOLatin1+ (or Stan‐
869 dard+)].
870
871 PS_COLOR_MODEL
872 Determines whether PostScript output should use RGB, HSV, CMYK,
873 or GRAY when specifying color [rgb]. Note if HSV is selected it
874 does not apply to images which in that case uses RGB. When
875 selecting GRAY, all colors will be converted to gray scale using
876 YIQ (television) conversion.
877
878 PS_COMMENTS
879 (static) If true we will issue comments in the PostScript file
880 that explain the logic of operations. These are useful if you
881 need to edit the file and make changes; otherwise you can set it
882 to false which yields a somewhat slimmer PostScript file
883 [false].
884
885 PS_IMAGE_COMPRESS
886 Determines if PostScript images are compressed using the
887 Run-Length Encoding scheme (rle), Lempel-Ziv-Welch compression
888 (lzw), DEFLATE compression (deflate[,level]), or not at all
889 (none) [deflate,5]. When specifying deflate, the compression
890 level (1--9) may optionally be appended.
891
892 PS_LINE_CAP
893 Determines how the ends of a line segment will be drawn. Choose
894 among a butt cap (default) where there is no projection beyond
895 the end of the path, a round cap where a semicircular arc with
896 diameter equal to the line-width is drawn around the end points,
897 and square cap where a half square of size equal to the
898 line-width extends beyond the end of the path [butt].
899
900 PS_LINE_JOIN
901 Determines what happens at kinks in line segments. Choose among
902 a miter join where the outer edges of the strokes for the two
903 segments are extended until they meet at an angle (as in a pic‐
904 ture frame; if the angle is too acute, a bevel join is used
905 instead, with threshold set by PS_MITER_LIMIT), round join where
906 a circular arc is used to fill in the cracks at the kinks, and
907 bevel join which is a miter join that is cut off so kinks are
908 triangular in shape [miter].
909
910 PS_MEDIA
911 Sets the physical format of the current plot paper [a4 (or let‐
912 ter)]. The following formats (and their widths and heights in
913 points) are recognized (Additional site-specific formats may be
914 specified in the gmt_custom_media.conf file in
915 $GMT_SHAREDIR/conf or ~/.gmt; see that file for details):
916
917 Media width height
918
919 · A0 2380 3368
920
921 · A1 1684 2380
922
923 · A2 1190 1684
924
925 · A3 842 1190
926
927 · A4 595 842
928
929 · A5 421 595
930
931 · A6 297 421
932
933 · A7 210 297
934
935 · A8 148 210
936
937 · A9 105 148
938
939 · A10 74 105
940
941 · B0 2836 4008
942
943 · B1 2004 2836
944
945 · B2 1418 2004
946
947 · B3 1002 1418
948
949 · B4 709 1002
950
951 · B5 501 709
952
953 · archA 648 864
954
955 · archB 864 1296
956
957 · archC 1296 1728
958
959 · archD 1728 2592
960
961 · archE 2592 3456
962
963 · flsa 612 936
964
965 · halfletter 396 612
966
967 · statement 396 612
968
969 · note 540 720
970
971 · letter 612 792
972
973 · legal 612 1008
974
975 · 11x17 792 1224
976
977 · tabloid 792 1224
978
979 · ledger 1224 792
980
981 For a completely custom format (e.g., for large format plotters)
982 you may also specify WxH, where W and H are in points unless you
983 append a unit to each dimension (c, i, m or p [Default]).
984
985 PS_MITER_LIMIT
986 Sets the threshold angle in degrees (integer in range [0,180])
987 used for mitered joins only. When the angle between joining line
988 segments is smaller than the threshold the corner will be bev‐
989 elled instead of mitered. The default threshold is 35 degrees.
990 Setting the threshold angle to 0 implies the PostScript default
991 of about 11 degrees. Setting the threshold angle to 180 causes
992 all joins to be beveled.
993
994 PS_PAGE_COLOR
995 Sets the color of the imaging background, i.e., the paper
996 [white].
997
998 PS_PAGE_ORIENTATION
999 (* -P) Sets the orientation of the page. Choose portrait or
1000 landscape [landscape].
1001
1002 PS_SCALE_X
1003 Global x-scale (> 0) to apply to plot-coordinates before plot‐
1004 ting. Normally used to shrink the entire output down to fit a
1005 specific height/width [1.0].
1006
1007 PS_SCALE_Y
1008 Global y-scale (> 0) to apply to plot-coordinates before plot‐
1009 ting. Normally used to shrink the entire output down to fit a
1010 specific height/width [1.0].
1011
1012 PS_TRANSPARENCY
1013 Sets the transparency mode to use when preparing PS for render‐
1014 ing to PDF. Choose from Color, ColorBurn, ColorDodge, Darken,
1015 Difference, Exclusion, HardLight, Hue, Lighten, Luminosity, Mul‐
1016 tiply, Normal, Overlay, Saturation, SoftLight, and Screen [Nor‐
1017 mal].
1018
1019 TIME_EPOCH
1020 Specifies the value of the calendar and clock at the origin
1021 (zero point) of relative time units (see TIME_UNIT). It is a
1022 string of the form yyyy-mm-ddT[hh:mm:ss] (Gregorian) or
1023 yyyy-Www-ddT[hh:mm:ss] (ISO) Default is 1970-01-01T00:00:00, the
1024 origin of the UNIX time epoch.
1025
1026 TIME_INTERVAL_FRACTION
1027 Determines if partial intervals at the start and end of an axis
1028 should be annotated. If the range of the partial interval
1029 exceeds the specified fraction of the normal interval stride we
1030 will place the annotation centered on the partial interval
1031 [0.5].
1032
1033 TIME_IS_INTERVAL
1034 Used when input calendar data should be truncated and adjusted
1035 to the middle of the relevant interval. In the following discus‐
1036 sion, the unit u can be one of these time units: (y year, o
1037 month, u ISO week, d day, h hour, m minute, and s second).
1038 TIME_IS_INTERVAL can have any of the following three values: (1)
1039 OFF [Default]. No adjustment, time is decoded as given. (2) +nu.
1040 Activate interval adjustment for input by truncate to previous
1041 whole number of n units and then center time on the following
1042 interval. (3) -nu. Same, but center time on the previous inter‐
1043 val. For example, with TIME_IS_INTERVAL = +1o, an input data
1044 string like 1999-12 will be interpreted to mean
1045 1999-12-15T12:00:00.0 (exactly middle of December), while if
1046 TIME_IS_INTERVAL = off then that date is interpreted to mean
1047 1999-12-01T00:00:00.0 (start of December) [off].
1048
1049 TIME_REPORT
1050 Controls if a time-stamp should be issued at start of all
1051 progress reports. Choose among TIMER_CLOCK (absolute time
1052 stamp), TIMER_ELAPSED (time since start of session), or
1053 TIMER_NONE [Default].
1054
1055 TIME_SYSTEM
1056 Shorthand for a combination of TIME_EPOCH and TIME_UNIT, speci‐
1057 fying which time epoch the relative time refers to and what the
1058 units are. Choose from one of the preset systems below (epoch
1059 and units are indicated):
1060
1061 JD -4713-11-25T12:00:00 d (Julian Date)
1062
1063 MJD 1858-11-17T00:00:00 d (Modified Julian Date)
1064
1065 J2000 2000-01-01T12:00:00 d (Astronomical time)
1066
1067 S1985 1985-01-01T00:00:00 s (Altimetric time)
1068
1069 UNIX 1970-01-01T00:00:00 s (UNIX time)
1070
1071 RD0001 0001-01-01T00:00:00 s
1072
1073 RATA 0000-12-31T00:00:00 d
1074
1075 This parameter is not stored in the gmt.conf file but is trans‐
1076 lated to the respective values of TIME_EPOCH and TIME_UNIT.
1077
1078 TIME_UNIT
1079 Specifies the units of relative time data since epoch (see
1080 TIME_EPOCH). Choose y (year - assumes all years are 365.2425
1081 days), o (month - assumes all months are of equal length y/12),
1082 d (day), h (hour), m (minute), or s (second) [s].
1083
1084 TIME_WEEK_START
1085 When weeks are indicated on time axes, this parameter determines
1086 the first day of the week for Gregorian calendars. (The ISO
1087 weekly calendar always begins weeks with Monday.) [Monday (or
1088 Sunday)].
1089
1090 TIME_Y2K_OFFSET_YEAR
1091 When 2-digit years are used to represent 4-digit years (see var‐
1092 ious FORMAT_DATEs), TIME_Y2K_OFFSET_YEAR gives the first year in
1093 a 100-year sequence. For example, if TIME_Y2K_OFFSET_YEAR is
1094 1729, then numbers 29 through 99 correspond to 1729 through
1095 1799, while numbers 00 through 28 correspond to 1800 through
1096 1828. [1950].
1097
1099 gmt , gmtdefaults , gmtcolors , gmtget , gmtset
1100
1102 2019, P. Wessel, W. H. F. Smith, R. Scharroo, J. Luis, and F. Wobbe
1103
1104
1105
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11075.4.5 Feb 24, 2019 GMT.CONF(5)