GMTDEFAULTS

NAME
SYNOPSIS
DESCRIPTION
GMT PARAMETERS
EXAMPLES
BUGS
SEE ALSO

NAME

gmtdefaults − To list current GMT defaults

SYNOPSIS

gmtdefaults −D[u|s] | −L

DESCRIPTION

gmtdefaults lists the GMT parameter defaults if the option −D is used. There are three ways to change some of the settings: (1) Use the command gmtset, (2) use any texteditor to edit the file .gmtdefaults4 in your home or current directory (if you do not have this file, run gmtdefaults -D > ~/.gmtdefaults4 to get one with the system default settings), or (3) overrid any parameter by specifying one or more −−PARAMETER=VALUE statements on the commandline of any GMT command (PARAMETER and VALUE are any combination listed below). The first two options are permanent changes until explicitly changed back, while the last option is emphemeral and only applies to the single GMT command that received the override. GMT can provide default values in US or SI units. This choice is determined by the contents of the gmt.conf file in GMT’s share directory.

−D

Print the system GMT defaults to standard output. Append u for US defaults or s for SI defaults. [−D alone gives current choice in gmt.conf].

−L

Print the user’s currently active defaults to standard output.

Your currently active defaults come from the .gmtdefaults4 file in the current working directory, if present; else from the .gmtdefaults4 file in your home directory, if present; else from the system defaults set at the time GMT was compiled.

GMT PARAMETERS

The following is a list of the parameters that are user-definable in GMT. The parameter names are always given in UPPER CASE. The parameter values are case-insensitive unless otherwise noted. The system defaults are given in brackets [ for SI (and US) ]. Those marked * can be set on the command line as well (the corresponding option is given in parentheses). Note that default distances and lengths below are given in both cm or inch; the chosen default depends on your choice of default unit (see MEASURE_UNIT). You can explicitly specify the unit used for distances and lengths by appending c (cm), i (inch), m (meter), or p (points). When no unit is indicated the value will be assumed to be in the unit set by MEASURE_UNIT. Note that the printer resolution DOTS_PR_INCH is always the number of dots or pixels per inch. Several parameters take only TRUE or FALSE.

ANNOT_MIN_ANGLE

If the angle between the map boundary and the annotation baseline is less than this minimum value (in degrees), the annotation is not plotted (this may occur for certain oblique projections.) Give a value in the range 0−90. [20]

ANNOT_MIN_SPACING

If an annotation would be plotted less than this minimum distance from its closest neighbor, the annotation is not plotted (this may occur for certain oblique projections.) [0]

ANNOT_FONT_PRIMARY

Font used for upper annotations, etc. [Helvetica]. Specify either the font number or the font name (case sensitive!). The 35 available fonts are:
0 Helvetica
1 Helvetica-Bold
2 Helvetica-Oblique
3 Helvetica-BoldOblique
4 Times-Roman
5 Times-Bold
6 Times-Italic
7 Times-BoldItalic
8 Courier
9 Courier-Bold
10 Courier-Oblique
11 Courier-BoldOblique
12 Symbol
13 AvantGarde-Book
14 AvantGarde-BookOblique
15 AvantGarde-Demi
16 AvantGarde-DemiOblique
17 Bookman-Demi
18 Bookman-DemiItalic
19 Bookman-Light
20 Bookman-LightItalic
21 Helvetica-Narrow
22 Helvetica-Narrow-Bold
23 Helvetica-Narrow-Oblique
24 Helvetica-Narrow-BoldOblique
25 NewCenturySchlbk-Roman
26 NewCenturySchlbk-Italic
27 NewCenturySchlbk-Bold
28 NewCenturySchlbk-BoldItalic
29 Palatino-Roman
30 Palatino-Italic
31 Palatino-Bold
32 Palatino-BoldItalic
33 ZapfChancery-MediumItalic
34 ZapfDingbats

ANNOT_FONT_SIZE_PRIMARY

Font size (> 0) in points for map annotations. [14]

ANNOT_FONT_SECONDARY

Font to use for time axis secondary annotations. See ANNOT_FONT_PRIMARY for available fonts [Helvetica].

ANNOT_FONT_SIZE_SECONDARY

Font size (> 0) for time axis secondary annotations in points [16].

ANNOT_OFFSET_PRIMARY

Distance from end of tickmark to start of annotation [0.2c (or 0.075i)]. A negative offset will place the annotation inside the map border.

ANNOT_OFFSET_SECONDARY

Distance from base of primary annotation to the top of the secondary annotation [0.2c (or 0.075i)] (Only applies to time axes with both primary and secondary annotations).

BASEMAP_AXES

Sets which axes to draw and annotate. Case sensitive: Upper case means both draw and annotate, lower case means draw axis only. [WESN].

BASEMAP_FRAME_RGB

Color used to draw map boundaries and annotations. Give a red/green/blue triplet, with each element in the 0−255 range. [0/0/0] (black).

BASEMAP_TYPE

Choose between plain and fancy (thick boundary, alternating black/white frame; append + for rounded corners) [fancy]. For some map projections (e.g., Oblique Mercator), plain is the only option even if fancy is set as default. In general, fancy only applies to situations where the projected x and y directions parallel the lon and lat directions (e.g., rectangular projections, polar projections).

CHAR_ENCODING

Names the eight bit character set being used for text in files and in command line parameters. This allows GMT to ensure that the PostScript output generates the correct characters on the plot.. Choose from Standard, Standard+, ISOLatin1, ISOLatin1+, and ISO-8859-x (where x is in the ranges 1-10 or 13-15). See Appendix F for details [ISOLatin1+ (or Standard+)].

COLOR_BACKGROUND

Color used for the background of images (i.e., when z < lowest colortable entry). Give a red/green/blue triplet, with each element in the 0−255 range. [0/0/0] (black)

COLOR_FOREGROUND

Color used for the foreground of images (i.e., when z > highest colortable entry). Give a red/green/blue triplet, with each element in the 0−255 range. [255/255/255] (white)

COLOR_IMAGE

Selects which operator to use when rendering bit-mapped color images. Due to the lack of the colorimage operator in some PostScript implementations, GMT offers 2 different options:

adobe (Adobe’s colorimage definition) [Default].
tiles (Plot image as many individual rectangles).

COLOR_MODEL

Selects if color palette files contain rgb values (r,g,b in 0-255 range) or HSV values (h in 0-360, s,v in 0-1 range). A COLOR_MODE setting in the color palette file will override this setting. [rgb].

COLOR_NAN

Color used for the non-defined areas of images (i.e., where z == NaN). Give a red/green/blue triplet, with each element in the 0−255 range. [128/128/128] (gray)

D_FORMAT

Output format (C language printf syntax) to be used when printing double precision floating point numbers. For geographic coordinates, see OUTPUT_DEGREE_FORMAT. [%lg].

DEGREE_SYMBOL

Determines what symbol is used to plot the degree symbol on geographic map annotations. Choose between ring, degree, colon, or none [ring].

DOTS_PR_INCH

Resolution of the plotting device (dpi). Note that in order to be as compact as possible, GMT PostScript output uses integer formats only so the resolution should be set depending on what output device you are using. E.g, using 300 and sending the output to a Linotype 300 phototypesetter (2470 dpi) will not take advantage of the extra resolution (i.e., positioning on the page and line thicknesses are still only done in steps of 1/300 inch; of course, text will look smoother) [300].

ELLIPSOID

The (case sensitive) name of the ellipsoid used for the map projections [WGS-84]. Choose among

WGS-84 1984 World Geodetic System [Default]
OSU91A 1991 Ohio State University
OSU86F 1986 Ohio State University
Engelis 1985 Goodard Earth Models
SGS-85 1985 Soviet Geodetic System
MERIT-83 1983 United States Naval Observatory
GRS-80 1980 International Geodetic Reference System
Lerch 1979 For geoid modelling
ATS77 1977 Average Terrestrial System, Canada Maritime provinces
IAG-75 1975 International Association of Geodesy
Indonesian 1974 Applies to Indonesia
WGS-72 1972 World Geodetic System
NWL-10D 1972 Naval Weapons Lab (Same as WGS-72)
South-American 1969 Applies to South America
Fischer-1968 1968 Used by NASA for Mercury program
Modified-Mercury-1968 1968 Same as Fischer-1968
GRS-67 1967 International Geodetic Reference System
International-1967 1967 Worldwide use
WGS-66 1966 World Geodetic System
NWL-9D 1966 Naval Weapons Lab (Same as WGS-66)
Australian 1965 Applies to Australia
APL4.9 1965 Appl. Physics
Kaula 1961 From satellite tracking
Hough 1960 Applies to the Marshall Islands
WGS-60 1960 World Geodetic System
Fischer-1960 1960 Used by NASA for Mercury program
Mercury-1960 1960 Same as Fischer-1960
Modified-Fischer-1960 1960 Applies to Singapore
Fischer-1960-SouthAsia 1960 Same as Modified-Fischer-1960
Krassovsky 1940 Used in the (now former) Soviet Union
War-Office 1926 Developed by G. T. McCaw
International-1924 1924 Worldwide use
Hayford-1909 1909 Same as the International 1924
Helmert-1906 1906 Applies to Egypt
Clarke-1880 1880 Applies to most of Africa, France
Clarke-1880-Arc1950 1880 Modified Clarke-1880 for Arc 1950
Clarke-1880-IGN 1880 Modified Clarke-1880 for IGN
Clarke-1880-Jamaica 1880 Modified Clarke-1880 for Jamaica
Clarke-1880-Merchich 1880 Modified Clarke-1880 for Merchich
Clarke-1880-Palestine 1880 Modified Clarke-1880 for Palestine
Andrae 1876 Applies to Denmark and Iceland
Clarke-1866 1866 Applies to North America, the Philippines
Clarke-1866-Michigan 1866 Modified Clarke-1866 for Michigan
Struve 1860 Friedrich Georg Wilhelm Struve
Clarke-1858 1858 Clarke’s early ellipsoid
Airy 1830 Applies to Great Britain
Airy-Ireland 1830 Applies to Ireland in 1965
Modified-Airy 1830 Same as Airy-Ireland
Bessel 1841 Applies to Central Europe, Chile, Indonesia
Bessel-Schwazeck 1841 Applies to Namibia
Bessel-Namibia 1841 Same as Bessel-Schwazeck
Bessel-NGO1948 1841 Modified Bessel for NGO 1948
Everest-1830 1830 India, Burma, Pakistan, Afghanistan, Thailand
Everest-1830-Kalianpur 1830 Modified Everest for Kalianpur (1956)
Everest-1830-Kertau 1830 Modified Everest for Kertau, Malaysia & Singapore
Everest-1830-Timbalai 1830 Modified Everest for Timbalai, Sabah Sarawak
Everest-1830-Pakistan 1830 Modified Everest for Pakistan
Walbeck 1819 First least squares solution by Finnish astronomer
Plessis 1817 Old ellipsoid used in France
Delambre 1810 Applies to Belgium
CPM 1799 Comm. des Poids et Mesures, France
Maupertius 1738 Really old ellipsoid used in France
Sphere 1980 The mean radius in GRS-80 (for spherical/plate tectonics applications)

Note that for some global projections, GMT may default to GRS-80 Sphere regardless of ellipsoid actually chosen. A warning will be given when this happens. If a different ellipsoid name than those mentioned here is given, GMT will attempt to open a file with that name in the current directory, and read a single record that contains the ellipsoid name, year, major-axis (in m), minor-axis (in m), and flattening (f) from the first record, where the fields must be separated by white-space (not commas). This way a custom ellipsoid (e.g., those used for other planets) may be used. A negative flattening means GMT will recalculate flattening from the two radii.

FIELD_DELIMITER

This setting determines what character will separate ASCII output data columns written by GMT. Choose from tab, space, comma, and none [tab].

FRAME_PEN

Thickness of pen used to draw plain map frame in dpi units or points (append p) [1.25p].

FRAME_WIDTH

Width (> 0) of map borders for fancy map frame [0.2c (or 0.075i)].

GLOBAL_X_SCALE

Global x-scale (> 0) to apply to plot-coordinates before plotting. Normally used to shrink the entire output down to fit a specific height/width [1.0].

GLOBAL_Y_SCALE

Same, but for y-coordinates [1.0].

GRID_CROSS_SIZE_PRIMARY

Size (>= 0) of grid cross at lon-lat intersections. 0 means draw continuous gridlines instead [0].

GRID_PEN_PRIMARY

Pen thickness used to draw grid lines in dpi units or points (append p) [0.25p].

GRID_CROSS_SIZE_SECONDARY

Size (>= 0) of grid cross at secondary lon-lat intersections. 0 means draw continuous gridlines instead [0].

GRID_FORMAT

Default file format for grids, with optional scale, offset and invalid value, written as ff/scale/offset/invalid. The 2-letter format indicator can be one of [bcnsr][bsifd]. The first letter indicates native GMT binary, old format NetCDF, COARDS-compliant NetCDF, Surfer format or Sun Raster format. The second letter stands for byte, short, int, float and double, respectively. When /invalid is omitted the appropriate value for the given format is used (NaN or largest negative). When /scale/offset is omitted, /1.0/0.0 is used. [nf].

GRID_PEN_SECONDARY

Pen thickness used to draw grid lines in dpi units or points (append p) [0.5p].

GRIDFILE_SHORTHAND

If TRUE, all gridfile names are examined to see if they use the file extension shorthand discussed in Section 4.17 of the GMT Technical Reference and Cookbook. If FALSE, no filename expansion is done [FALSE].

HEADER_FONT

Font to use when plotting headers. See ANNOT_FONT_PRIMARY for available fonts [Helvetica].

HEADER_FONT_SIZE

Font size (> 0) for header in points [36].

HEADER_OFFSET

Distance from top of axis annotations (or axis label, if present) to base of plot header [0.5c (or 0.1875i)].

HSV_MIN_SATURATION

Minimum saturation (0−1) assigned for most negative intensity value [1.0].

HSV_MAX_SATURATION

Maximum saturation (0−1) assigned for most positive intensity value [0.1].

HSV_MIN_VALUE

Minimum value (0−1) assigned for most negative intensity value [0.3].

HSV_MAX_VALUE

Maximum value (0−1) assigned for most positive intensity value [1.0].

INPUT_CLOCK_FORMAT

Formatting template that indicates how an input clock string is formatted. This template is then used to guide the reading of clock strings in data fields. To properly decode 12-hour clocks, append am or pm (or upper case) to match your data records. As examples, try hh:mm, hh:mm:ssAM, etc. [hh:mm:ss].

INPUT_DATE_FORMAT

Formatting template that indicates how an input date string is formatted. This template is then used to guide the reading of date strings in data fields. You may specify either Gregorian calendar format or ISO week calendar format. Gregorian calendar: Use any combination of yyyy (or yy for 2-digit years; if so see Y2K_OFFSET_YEAR), mm (or o for abbreviated month name in the current time language), and dd, with or without delimiters. For day-of-year data, use jjj instead of mm and/or dd. Examples can be ddmmyyyy, yy-mm-dd, dd-o-yyyy, yyyy/dd/mm, yyyy-jjj, etc. ISO Calendar: Expected template is yyyy[-]W[-]ww[-]d, where ww is ISO week and d is ISO week day. Either template must be consistent, e.g., you cannot specify months if you don’t specify years. Examples are yyyyWwwd, yyyy-Www, etc. [yyyy-mm-dd].

INTERPOLANT

Determines if linear (linear), Akima’s spline (akima), or natural cubic spline (cubic) should be used for 1-D interpolations in various programs [akima].

IO_HEADER

(* −H) Specifies whether input/output ASCII files have header record(s) or not [FALSE].

N_HEADER_RECS

Specifies how many header records to expect if −H is turned on [1].

LABEL_FONT

Font to use when plotting labels below axes. See ANNOT_FONT_PRIMARY for available fonts [Helvetica].

LABEL_FONT_SIZE

Font size (> 0) for labels in points [24].

LABEL_OFFSET

Distance from base of axis annotations to the top of the axis label [0.3c (or 0.1125i)].

LINE_STEP

Determines the maximum length (> 0) of individual straight line-segments when drawing arcuate lines [0.025c (or 0.01i)]

MAP_SCALE_FACTOR

Changes the default map scale factor used for the Polar Stereographic [0.9996], UTM [0.9996], and Transverse Mercator [1] projections in order to minimize areal distortion. Provide a new scale-factor or leave as default.

MAP_SCALE_HEIGHT

Sets the height (> 0) on the map of the map scale bars drawn by various programs [0.2c (or 0.075i)].

MEASURE_UNIT

Sets the unit length. Choose between cm, inch, m, and point. [cm]. Note that, in GMT, one point is defined as 1/72 inch (the PostScript definition), while it is often defined as 1/72.27 inch in the typesetting industry. There is no universal definition.

N_COPIES

(* −c) Number of plot copies to make [1].

OBLIQUE_ANNOTATION

This integer is a sum of 6 bit flags (most of which only are relevant for oblique projections): If bit 1 is set (1), annotations will occur wherever a gridline crosses the map boundaries, else longitudes will be annotated on the lower and upper boundaries only, and latitudes will be annotated on the left and right boundaries only. If bit 2 is set (2), then longitude annotations will be plotted horizontally. If bit 3 is set (4), then latitude annotations will be plotted horizontally. If bit 4 is set (8), then oblique tickmarks are extended to give a projection equal to the specified tick_length. If bit 5 is set (16), tickmarks will be drawn normal to the border regardless of gridline angle. If bit 6 is set (32), then latitude annotations will be plotted parallel to the border. To set a combination of these, add up the values in parentheses. [1].

OUTPUT_CLOCK_FORMAT

Formatting template that indicates how an output clock string is to be formatted. This template is then used to guide the writing of clock strings in data fields. To use a floating point format for the smallest unit (e.g. seconds), append .xxx, where the number of x indicates the desired precision. If no floating point is indicated then the smallest specified unit will be rounded off to nearest integer. For 12-hour clocks, append am, AM, a.m., or A.M. (GMT will replace a|A with p|P for pm). If your template starts with a leading hyphen (-) then each integer item (y,m,d) will be printed without leading zeros (default uses fixed width formats). As examples, try hh:mm, hh.mm.ss, hh:mm:ss.xxxx, hha.m., etc. [hh:mm:ss].

OUTPUT_DATE_FORMAT

Formatting template that indicates how an output date string is to be formatted. This template is then used to guide the writing of date strings in data fields. You may specify either Gregorian calendar format or ISO week calendar format. Gregorian calendar: Use any combination of yyyy (or yy for 2-digit years; if so see Y2K_OFFSET_YEAR), mm (or o for abbreviated month name in the current time language), and dd, with or without delimiters. For day-of-year data, use jjj instead of mm and/or dd. As examples, try yy/mm/dd, yyyy=jjj, dd-o-yyyy, dd-mm-yy, yy-mm, etc. ISO Calendar: Expected template is yyyy[-]W[-]ww[-]d, where ww is ISO week and d is ISO week day. Either template must be consistant, e.g., you cannot specify months if you don’t specify years. As examples, try yyyyWww, yy-W-ww-d, etc. If your template starts with a leading hyphen (-) then each integer item (y,m,d) will be printed without leading zeros (default uses fixed width formats) [yyyy-mm-dd].

OUTPUT_DEGREE_FORMAT

Formatting template that indicates how an output geographical coordinate is to be formatted. This template is then used to guide the writing of geographical coordinates in data fields. The template is in general of the form [+|-]D or [+|-]ddd[:mm[:ss]][.xxx][F]. The various terms have the following purpose:

+ means output longitude in the 0 to 360 range [-180/+180]
- means output longitude in the -360 to 0 range [-180/+180]
D Use D_FORMAT for floating point degrees.
ddd Fixed format integer degrees
: delimiter used
mm Fixed format integer arc minutes
ss Fixed format integer arc seconds
F Encode sign using WESN suffix

The default is +D.

PAGE_COLOR

Sets the color of the imaging background, i.e., the paper. Give a red/green/blue triplet, with each element in the 0−255 range. [255/255/255] (white).

PAGE_ORIENTATION

(* −P) Sets the orientation of the page. Choose portrait or landscape [landscape].

PAPER_MEDIA

Sets the physical format of the current plot paper [A4]. The following formats (and their widths and heights in points) are recognized (Additional site-specific formats may be specified in the gmtmedia.d file in $GMTHOME/share; see that file for details):

Media width height
A0 2380 3368
A1 1684 2380
A2 1190 1684
A3 842 1190
A4 595 842
A5 421 595
A6 297 421
A7 210 297
A8 148 210
A9 105 148
A10 74 105
B0 2836 4008
B1 2004 2836
B2 1418 2004
B3 1002 1418
B4 709 1002
B5 501 709
archA 648 864
archB 864 1296
archC 1296 1728
archD 1728 2592
archE 2592 3456
flsa 612 936
halfletter 396 612
note 540 720
letter 612 792
legal 612 1008
11x17 792 1224
ledger 1224 792

For a completely custom format (e.g., for large format plotters) you may also specify Custom_WxH, where W and H are in points. To force the printer to request a manual paper feed, append ’-’ to the media name, e.g., A3- will require the user to insert a A3 paper into the printer’s manual feed slot. To indicate you are making an EPS file, append ’+’ to the media name. Then, GMT will attempt to issue a tight bounding box [Default Bounding Box is the paper dimension].

PLOT_CLOCK_FORMAT

Formatting template that indicates how an output clock string is to be plotted. This template is then used to guide the formatting of clock strings in plot annotations. See OUTPUT_CLOCK_FORMAT for details. [hh:mm:ss].

PLOT_DATE_FORMAT

Formatting template that indicates how an output date string is to be plotted. This template is then used to guide the plotting of date strings in data fields. See OUTPUT_DATE_FORMAT for details. In addition, you may use a single o instead of mm (to plot month name) and u instead of W[-]ww to plot "Week ##". Both of these text strings will be affected by the TIME_LANGUAGE setting. [yyyy-mm-dd].

PLOT_DEGREE_FORMAT

Formatting template that indicates how an output geographical coordinate is to be plotted. This template is then used to guide the plotting of geographical coordinates in data fields. See OUTPUT_DEGREE_FORMAT for details. In addition, you can append A which plots the absolute value of the coordinate. The default is +ddd:mm:ss. Not all items may be plotted as this depends on the annotation interval.

PS_COLOR

Determines whether PostScript output should use RGB or CMYK when specifying color. Select from rgb or cmyk [rgb].

PS_IMAGE_COMPRESS

Determines if PostScript images are compressed using the Run-Length Encoding scheme (rle), LZW compression (lzw), or not at all (none) [none].

PS_IMAGE_FORMAT

Determines whether images created in PostScript should use ascii or binary format. The latter takes up less space and executes faster but may choke some printers, especially those off serial ports. Select ascii or bin [ascii].

PS_LINE_CAP

Determines how the ends of a line segment will be drawn. Choose among a butt cap (default) where there is no projection beyond the end of the path, a round cap where a semicircular arc with diameter equal to the linewidth is drawn around the end points, and square cap where a half square of size equal to the linewidth extends beyond the end of the path [butt].

PS_LINE_JOIN

Determines what happens at kinks in line segments. Choose among a miter join where the outer edges of the strokes for the two segments are extended until they meet at an angle (as in a picture frame; if the angle is too acute, a bevel join is used instead, with threshold set by PS_MITER_LIMIT), round join where a circular arc is used to fill in the cracks at the kinks, and bevel join which is a miter join that is cut off so kinks are triangular in shape [miter].

PS_MITER_LIMIT

Sets the threshold angle (integer in 0-180 range) used for mitered joins. 0 and 180 are special flag values that imply the PostScript default [11] and always bevels, respectively. Other values sets the acute angle used to decide between mitered and bevelled.

TICK_LENGTH

The length of a tickmark. Normally, tickmarks are drawn on the outside of the map boundaries. To select interior tickmarks, use a negative tick_length [0.2c (or 0.075i)].

TICK_PEN

The pen thickness to be used for tickmarks in dpi units or points (append p) [0.5p].

TIME_FORMAT_PRIMARY

Controls how primary month-, week-, and weekday-names are formatted. Choose among full, abbreviated, and character. If the leading f, a, or c are replaced with F, A, and C the entire annotation will be in upper case.

TIME_FORMAT_SECONDARY

Controls how secondary month-, week-, and weekday-names are formatted. Choose among full, abbreviated, and character. If the leading f, a, or c are replaced with F, A, and C the entire annotation will be in upper case.

TIME_EPOCH

This parameter is active only when TIME_SYSTEM is set to OTHER. It is a string of the form yyyy-mm-ddThh:mm:ss (Gregorian) or yyyy-Www-ddThh:mm:ss (ISO) indicating the value of the calendar and clock at the origin (zero point) of relative time units.

TIME_IS_INTERVAL

Used when input calendar data should be truncated and adjusted to the middle of the relevant interval. In the following discussion, the unit u can be one of these time units: (y year, o month, u ISO week, d day, h hour, m minute, and c second). TIME_IS_INTERVAL can have any of the following three values: (1) OFF [Default]. No adjustment, time is decoded as given. (2) +nu. Activate interval adjustment for input by truncate to previous whole number of n units and then center time on the following interval. (3) -nu. Same, but center time on the previous interval. For example, with TIME_IS_INTERVAL = +1o, an input data string like 1999-12 will be interpreted to mean 1999-12-15T12:00:00.0 (exactly middle of December), while if TIME_IS_INTERVAL = OFF then that date is interpreted to mean 1999-12-1T00:00:00.0 (start of December).

TIME_INTERVAL_FRACTION

Determines if partial intervals at the start and end of an axis should be annotated. If the range of the partial interval exceeds the specified fraction of the normal interval stride we will place the annotation centered on the partial interval [0.5].

TIME_LANGUAGE

Language to use when plotting calendar items such as months and days. Select from:
BR Brazilian Portuguese
CN1 Simplified Chinese
CN2 Traditional Chinese
DE German
DK Danish
EH Basque
ES Spanish
FI Finnish
FR French
GR Greek
HU Hungarian
IE Irish
IL Hebrew
IS Icelandic
IT Italian
JP Japanese
NL Dutch
NO Norwegian
PL Polish
PT Portuguese
RU Russian
SE Swedish
SG Scottish Gaelic
TO Tongan
TR Turkish
UK British English
US US English

If your language is not supported, please examine the $GMTHOME/share/time/us.d file and make a similar file. Please submit it to the GMT Developers for official inclusion.

TIME_SYSTEM

Determines what the time epoch relative time refers to and what the units are. Choose from one of the preset systems below (epoch and units are indicated):
JD Julian Date, -4713-11-25T12:00:00 d
MJD Modified Julian Date, 1858-11-27T00:00:00 d
J2000 2000-01-01T00:00:00 d
S1985 1985-01-01T00:00:00 c
UNIX 1970-01-01T00:00:00 c
or specify OTHER and supply your own TIME_EPOCH and TIME_UNIT settings [J2000].

TIME_UNIT

This parameter is active only when TIME_SYSTEM is set to OTHER, and specifies the units of relative time data. Choose y (year), d (day), h (hour), m (minute), or c (second).

TIME_WEEK_START

When weeks are indicated on time axes, this parameter determines the first day of the week for Gregorian calendars. (The ISO weekly calendar always begins weeks with Monday.) [Monday (or Sunday)].

UNIX_TIME

(* −U) Specifies if a UNIX system time stamp should be plotted at the lower left corner of the plot [FALSE].

UNIX_TIME_POS

(* −U) Sets the position of the UNIX time stamp relative to the current plots lower left corner [-2c/-2c (or -0.75i/-0.75i)].

VECTOR_SHAPE

Determines the shape of the head of a vector. Normally (i.e., for vector_shape = 0), the head will be triangular, but can be changed to an arrow (1) or an open V (2). Intermediate settings give something in between. Negative values (up to -2) are allowed as well [0].

VERBOSE

(* −V) Determines if GMT programs should display run-time information or run silently [FALSE].

X_AXIS_LENGTH

Sets the default length (> 0) of the x-axis [25c (or 9i)].

Y_AXIS_LENGTH

Sets the default length (> 0) of the y-axis [15c (or 6i)].

X_ORIGIN

(* −X) Sets the x-coordinate of the origin on the paper for a new plot [2.5c (or 1i)]. For an overlay, the default offset is 0.

Y_ORIGIN

(* −Y) Sets the y-coordinate of the origin on the paper for a new plot [2.5c (or 1i)]. For an overlay, the default offset is 0.

Y2K_OFFSET_YEAR

When 2-digit years are used to represent 4-digit years (see various DATE_FORMATs), Y2K_OFFSET_YEAR gives the first year in a 100-year sequence. For example, if Y2K_OFFSET_YEAR is 1729, then numbers 29 through 99 correspond to 1729 through 1799, while numbers 00 through 28 correspond to 1800 through 1828. [1950].

XY_TOGGLE

(* −:) Set if the first two columns of input and output files contain (latitude,longitude) or (y,x) rather than the expected (longitude,latitude) or (x,y). FALSE means we have (x,y) both on input and output. TRUE means both input and output should be (y,x). IN means only input has (y,x), while OUT means only output should be (y,x). [FALSE].

Y_AXIS_TYPE

Determines if the annotations for a y-axis (for linear projections) should be plotted horizontally (hor_text) or vertically (ver_text) [hor_text].

EXAMPLES

To get a copy of the GMT parameter defaults in your home directory, run

gmtdefaults −D > ~/.gmtdefaults4

You may now change the settings by editing this file using a text editor of your choice, or use gmtset to change specified parameters on the command line.

BUGS

If you have typographical errors in your .gmtdefaults4 file(s), a warning message will be issued, and the GMT defaults for the affected parameters will be used.

SEE ALSO

GMT(l), gmtset(l)