grdseamount
grdseamount - Compute synthetic seamount (Gaussian or cone, circular or elliptical) bathymetry
Synopsis
grdseamount [ intable ]
-Ixinc[unit][=|+][/yinc[unit][=|+]]
-R[unit]xmin/xmax/ymin/ymax[r]
[ -A[out/in] ] [ -C ] [ -E ] [ -Ggrdfile ] [ -L[cut] ]
[ -Nnorm ] [ -Sscale ] [ -T[flattening] ] [ -Zlevel ]
[ -V[level] ]
[ -bi[ncols][type][w][+L|+B] ]
[ -fg ]
[ -icols[l][sscale][ooffset][,...] ]
[ -r ]
Note: No space is allowed between the option flag and the associated arguments.
Description
grdseamount will compute the bathymetry for synthetic seamounts given their shape
parameters. We read a list with seamount locations and sizes and can evaluate either
Gaussian or conical shapes, which may be circular or elliptical, and optionally truncated.
Various scaling options are available to modify the result, including an option to add in
a background depth. The input must contain lon, lat, radius, height for each seamount.
For elliptical features (-E) we expect lon, lat, azimuth, semi-major, semi-minor,
radius, height instead. If flattening is specified (-T) then a final column with
flattening is expected.
Required Arguments
- -Ixinc[unit][=|+][/yinc[unit][=|+]]
- x_inc [and optionally y_inc] is the grid spacing. Optionally,
append a suffix modifier. Geographical (degrees) coordinates: Append
m to indicate arc minutes or s to indicate arc seconds. If one
of the units e, f, k, M, n or u is appended
instead, the increment is assumed to be given in meter, foot, km, Mile,
nautical mile or US survey foot, respectively, and will be converted to
the equivalent degrees longitude at the middle latitude of the region
(the conversion depends on PROJ_ELLIPSOID). If /y_inc is given
but set to 0 it will be reset equal to x_inc; otherwise it will be
converted to degrees latitude. All coordinates: If = is appended
then the corresponding max x (east) or y (north) may be slightly
adjusted to fit exactly the given increment [by default the increment
may be adjusted slightly to fit the given domain]. Finally, instead of
giving an increment you may specify the number of nodes desired by
appending + to the supplied integer argument; the increment is then
recalculated from the number of nodes and the domain. The resulting
increment value depends on whether you have selected a
gridline-registered or pixel-registered grid; see B. GMT File Formats for
details. Note: if -Rgrdfile is used then the grid spacing has
already been initialized; use -I to override the values.
- -R[unit]xmin/xmax/ymin/ymax[r] (more ...)
- Specify the region of interest.
Optional Arguments
- -A[out/in]
- Build a mask grid, append outside/inside values [1/NaN].
Here, height is ignored and -L, -N and -Z are disallowed
- -C
- Cone model [Default is Gaussian].
- -E
- Elliptical data format [Default is Circular]. Read lon, lat, azimuth,
major, minor, height (m) for each seamount.
- -Goutgrid
- Sets name of output gridfile.
- -L[cut]
- List area, volume, and mean height for each seamount; NO grid is created.
Optionally, append the noise-floor cutoff level [0].
- -Nnorm
- Normalize grid so maximum grid height equals norm.
- -Sscale
- Sets optional scale factor for radii [1].
- -T[flattening]
- Seamounts are to be truncated. Append flattening, otherwise we expect
it in last input column [no truncation].
- -Zlevel
- Add in background depth [0].
- -bi[ncols][type] (more ...)
- Select binary input. [Default is 3 input columns]. This option only applies
to xyz input files; see -Z for z tables.
- -fg
- Geographic grids (dimensions of longitude, latitude) will be converted to
km via a “Flat Earth” approximation using the current ellipsoid parameters.
- -h[i|o][n][+c][+d][+rremark][+rtitle] (more ...)
- Skip or produce header record(s). Not used with binary data.
- -icols[l][sscale][ooffset][,...] (more ...)
- Select input columns.
- -V[level] (more ...)
- Select verbosity level [c].
- -r (more ...)
- Set pixel node registration [gridline].
- -:[i|o] (more ...)
- Swap 1st and 2nd column on input and/or output.
- -^
- Print a short message about the syntax of the command, then exits (NOTE: on Windows use just -).
- +
- Print an extensive usage (help) message, including the explanation of
any module-specific option (but not the GMT common options), then exits.
- -?
- Print a complete usage (help) message, including the explanation of
options, then exits.
- --version
- Print GMT version and exit.
- --show-datadir
- Print full path to GMT share directory and exit.