GMTDEFAULTS

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, ~/.gmt or current directory (if you do not have this file, run gmtdefaults -D > ~/.gmtdefaults4 to get one with the system default settings), or (3) override 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 ephemeral 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_setup.conf file in GMT’s share directory.

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 file ~/.gmt/.gmtdefaults4, 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_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:

ANNOT_FONT_SIZE_PRIMARY

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

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 [16p].

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_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. Prepend ’+’ to replicate this color to the tick-, grid-, and frame-pens. [0/0/0] (black).

BASEMAP_TYPE

Choose between inside, graph, 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). For situations where all boundary ticks and annotations must be inside the maps (e.g., for preparing geotiffs), chose inside. Finally, graph is used for linear projections only and will extend the axis by 7.5% and add arrow heads.

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, as well as some PostScript editors inability to handle color gradations, GMT offers two different options:

COLOR_MODEL

Selects if color palette files contain RGB values (r,g,b in 0-255 range), HSV values (h in 0-360, s,v in 0-1 range), or CMYK values (c,m,y,k in 0-1 range). A COLOR_MODEL setting in the color palette file will override this setting. Internally, color interpolation takes place directly on the RGB values which can give unexpected hues, whereas interpolation directly on the HSV values better preserves the hues. Prepend the prefix "+" to force interpolation in the selected color system (does not apply to the CMYK system). For this additional option, the defaults take precedence over the color palette file [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. [%.12g].

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 : World Geodetic System [Default] (1984)
OSU91A : Ohio State University (1991)
OSU86F : Ohio State University (1986)
Engelis : Goddard Earth Models (1985)
SGS-85 : Soviet Geodetic System (1985)
TOPEX : Used commonly for altimetry (1990)
MERIT-83 : United States Naval Observatory (1983)
GRS-80 : International Geodetic Reference System (1980)
Hughes-1980 : Hughes Aircraft Company for DMSP SSM/I grid products (1980)
Lerch : For geoid modelling (1979)
ATS77 : Average Terrestrial System, Canada Maritime provinces (1977)
IAG-75 : International Association of Geodesy (1975)
Indonesian : Applies to Indonesia (1974)
WGS-72 : World Geodetic System (1972)
NWL-10D : Naval Weapons Lab (Same as WGS-72) (1972)
South-American : Applies to South America (1969)
Fischer-1968 : Used by NASA for Mercury program (1968)
Modified-Mercury-1968 : Same as Fischer-1968 (1968)
GRS-67 : International Geodetic Reference System (1967)
International-1967 : Worldwide use (1967)
WGS-66 : World Geodetic System (1966)
NWL-9D : Naval Weapons Lab (Same as WGS-66) (1966)
Australian : Applies to Australia (1965)
APL4.9 : Appl. Physics (1965)
Kaula : From satellite tracking (1961)
Hough : Applies to the Marshall Islands (1960)
WGS-60 : World Geodetic System (1960)
Fischer-1960 : Used by NASA for Mercury program (1960)
Mercury-1960 : Same as Fischer-1960 (1960)
Modified-Fischer-1960 : Applies to Singapore (1960)
Fischer-1960-SouthAsia : Same as Modified-Fischer-1960 (1960)
Krassovsky : Used in the (now former) Soviet Union (1940)
War-Office : Developed by G. T. McCaw (1926)
International-1924 : Worldwide use (1924)
Hayford-1909 : Same as the International 1924 (1909)
Helmert-1906 : Applies to Egypt (1906)
Clarke-1880 : Applies to most of Africa, France (1880)
Clarke-1880-Arc1950 : Modified Clarke-1880 for Arc 1950 (1880)
Clarke-1880-IGN : Modified Clarke-1880 for IGN (1880)
Clarke-1880-Jamaica : Modified Clarke-1880 for Jamaica (1880)
Clarke-1880-Merchich : Modified Clarke-1880 for Merchich (1880)
Clarke-1880-Palestine : Modified Clarke-1880 for Palestine (1880)
Andrae : Applies to Denmark and Iceland (1876)
Clarke-1866 : Applies to North America, the Philippines (1866)
Clarke-1866-Michigan : Modified Clarke-1866 for Michigan (1866)
Struve : Friedrich Georg Wilhelm Struve (1860)
Clarke-1858 : Clarke’s early ellipsoid (1858)
Airy : Applies to Great Britain (1830)
Airy-Ireland : Applies to Ireland in 1965 (1830)
Modified-Airy : Same as Airy-Ireland (1830)
Bessel : Applies to Central Europe, Chile, Indonesia (1841)
Bessel-Schwazeck : Applies to Namibia (1841)
Bessel-Namibia : Same as Bessel-Schwazeck (1841)
Bessel-NGO1948 : Modified Bessel for NGO 1948 (1841)
Everest-1830 : India, Burma, Pakistan, Afghanistan, Thailand (1830)
Everest-1830-Kalianpur : Modified Everest for Kalianpur (1956) (1830)
Everest-1830-Kertau : Modified Everest for Kertau, Malaysia & Singapore (1830)
Everest-1830-Timbalai : Modified Everest for Timbalai, Sabah Sarawak (1830)
Everest-1830-Pakistan : Modified Everest for Pakistan (1830)
Walbeck : First least squares solution by Finnish astronomer (1819)
Plessis : Old ellipsoid used in France (1817)
Delambre : Applies to Belgium (1810)
CPM : Comm. des Poids et Mesures, France (1799)
Maupertius : Really old ellipsoid used in France (1738)
Sphere : The mean radius in WGS-84 (for spherical/plate tectonics applications) (1984)
Moon : Moon (IAU2000) (2000)
Mercury : Mercury (IAU2000) (2000)
Venus : Venus (IAU2000) (2000)
Mars : Mars (IAU2000) (2000)
Jupiter : Jupiter (IAU2000) (2000)
Saturn : Saturn (IAU2000) (2000)
Uranus : Uranus (IAU2000) (2000)
Neptune : Neptune (IAU2000) (2000)
Pluto : Pluto (IAU2000) (2000)

Note that for some global projections, GMT may use a spherical approximation of the ellipsoid chosen, setting the flattening to zero, and using a mean radius. A warning will be given when this happens. If a different ellipsoid name than those mentioned here is given, GMT will attempt to parse the name to extract the semi-major axis (a in m) and the flattening. Formats allowed are:

This way a custom ellipsoid (e.g., those used for other planets) may be used. Further note that coordinate transformations in mapproject can also specify specific datums; see the mapproject man page for further details and how to view ellipsoid and datum parameters.

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

Pen attributes 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_CROSS_SIZE_SECONDARY

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

GRID_PEN_PRIMARY

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

GRID_PEN_SECONDARY

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

GRIDFILE_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].

GRIDFILE_SHORTHAND

If TRUE, all grid file 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 [36p].

HEADER_OFFSET

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

HISTORY

If TRUE, passes the history of past common command options via the hidden .gmtcommands4 file [TRUE].

HSV_MAX_SATURATION

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

HSV_MIN_SATURATION

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

HSV_MAX_VALUE

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

HSV_MIN_VALUE

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

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), natural cubic spline (cubic) or no interpolation (none) 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].

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 [24p].

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].

N_HEADER_RECS

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

NAN_RECORDS

Determines what happens when input records containing NaNs for x or y (and in some cases z) are read. Choose between skip, which will simply report how many bad records were skipped, and pass [Default], which will pass these records on to the calling programs. For most programs this will result in output records with NaNs as well, but some will interpret these NaN records to indicate gaps in a series; programs may then use that information to detect segmentation (if applicable).

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]. By default, longitudes will be reported in the -180/+180 range. The various terms have the following purpose:

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).

PAPER_MEDIA

Sets the physical format of the current plot paper [A4 (or Letter)]. The following formats (and their widths and heights in points) are recognized (Additional site-specific formats may be specified in the gmt_custom_media.conf file in $GMT_SHAREDIR/conf or ~/.gmt; see that file for details):

For a completely custom format (e.g., for large format plotters) you may also specify Custom_WxH, where W and H are in points unless you append a unit to each dimension (c, i, m or p [Default]). 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].

PAGE_ORIENTATION

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

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, TIME_FORMAT_PRIMARY and TIME_FORMAT_SECONDARY 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.

POLAR_CAP

Controls the appearance of gridlines near the poles for all azimuthal projections and a few others in which the geographic poles are plotted as points (Lambert Conic, Hammer, Mollweide, Sinusoidal, and van der Grinten). Specify either none (in which case there is no special handling) or pc_lat/pc_dlon. In that case, normal gridlines are only drawn between the latitudes -pc_lat/+pc_lat, and above those latitudes the gridlines are spaced at the (presumably coarser) pc_dlon interval; the two domains are separated by a small circle drawn at the pc_lat latitude [85/90]. Note for r-theta (polar) projection where r = 0 is at the center of the plot the meaning of the cap is reversed, i.e., the default 85/90 will draw a r = 5 radius circle at the center of the map with less frequent radial lines there.

PS_COLOR

Determines whether PostScript output should use RGB, HSV, CMYK, or GRAY when specifying color [rgb]. Note if HSV is selected it does not apply to images which in that case uses RGB. When selecting GRAY, all colors will be converted to gray scale using YIQ (television) conversion.

PS_IMAGE_COMPRESS

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

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 in degrees (integer in 0-180 range) used for mitered joins only. When the angle between joining line segments is smaller than the threshold the corner will be bevelled instead of mitered. The default threshold is 35 degrees. Setting the threshold angle to 0 implies the PostScript default of about 11 degrees. Setting the threshold angle to 180 causes all joins to be beveled.

PS_VERBOSE

If TRUE we will issue comments in the PostScript file that explain the logic of operations. These are useful if you need to edit the file and make changes; otherwise you can set it to FALSE which yields a somewhat slimmer PostScript file [FALSE].

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

Pen attributes to be used for tickmarks in dpi units or points (append p) [0.5p].

TIME_EPOCH

Specifies the value of the calendar and clock at the origin (zero point) of relative time units (see TIME_UNIT). It is a string of the form yyyy-mm-ddT[hh:mm:ss] (Gregorian) or yyyy-Www-ddT[hh:mm:ss] (ISO) Default is 2000-01-01T12:00:00, the epoch of the J2000 system.

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_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_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 1999-12-01T00:00:00.0 (start of December) [OFF].

TIME_LANGUAGE

Language to use when plotting calendar items such as months and days. Select from:

If your language is not supported, please examine the $GMT_SHAREDIR/time/us.d file and make a similar file. Please submit it to the GMT Developers for official inclusion. Custom language files can be placed in directories $GMT_SHAREDIR/time or ~/.gmt.

TIME_SYSTEM

Shorthand for a combination of TIME_EPOCH and TIME_UNIT, specifying which time epoch the relative time refers to and what the units are. Choose from one of the preset systems below (epoch and units are indicated):

This parameter is not stored in the .gmtdefaults4 file but is translated to the respective values of TIME_EPOCH and TIME_UNIT.

TIME_UNIT

Specifies the units of relative time data since epoch (see TIME_EPOCH). Choose y (year - assumes all years are 365.2425 days), o (month - assumes all months are of equal length y/12), d (day), h (hour), m (minute), or c (second) [d].

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)].

TRANSPARENCY

Makes printed material transparent. Specify transparency in percent: 0 is opaque (normal overlay plotting), 100 is fully transparent (i.e., nothing will show). Use either as a pair (stroke/fill) to set the transparency of stroked material (lines) or filled material (polygons) separately, or use a single number to set both to the same value [0].
Warning: Most printers and PostScript viewers can not print or will not show transparency. They will simply ignore your attempt to create transparency and will plot any material as opaque. Ghostscript and all its derivatives like ps2raster, Apple’s Preview and the CUPS printing system are among those programs incapable of dealing with transparency. If you want to view transparent material you need to use Acrobat Distiller to create a PDF file. Note that the settings of Acrobat Distiller need to be changed to make transparency effective: change /AllowTransparency to true in the .joboptions file.

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 justification and the position of the UNIX time stamp box relative to the current plots lower left corner of the plot [BL/-2c/-2c (or BL/-0.75i/-0.75i)].

UNIX_TIME_FORMAT

Defines the format of the time information in the UNIX time stamp. This format is parsed by the C function strftime, so that virtually any text can be used (even not containing any time information) [%Y %b %d %H:%M:%S].

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)].

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.

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_LENGTH

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

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.

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].

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].

SPECIFYING PENS

SPECIFYING FILL

SPECIFYING COLOR

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(1), gmtcolors(5), gmtget(1), gmtset(1)