pswiggle
pswiggle - Plot anomaly along track on a map
SYNOPSIS
pswiggle xyz_files -Jparameters -Rwest/east/south/north[r]
-Zscale [ -Aazimuth ] [ -Btickinfo ] [ -Ccenter ] [ -Dgap
] [ -Eazimuth/elevation ] [ -Gfillrgb ] [ -H[nrec] ] [
-Ifix_az ] [ -K ] [ -M[flag] ] [ -N ] [ -O ] [ -P ] [
-S[x]lon0/lat0/length[units] ] [ -Ttrack_pen ] [
-U[/dx/dy/][label] ] [ -V ] [ -Wwiggle_pen ] [ -Xx-shift
] [ -Yy-shift ] [ -ccopies ] [ -: ] [ -bi[s][n] ]
DESCRIPTION
pswiggle reads (x,y,z) triplets from files [or standard
input] and plots z as a function of distance along track.
This means that two consecutive (x,y) points define the
local distance axis, and the local z axis is then perpen
dicular to the distance axis. The user may set a preferred
positive anomaly plot direction, and if the positive nor
mal is outside the plus/minus 90 degree window around the
preferred direction, then 180 degrees are added to the
direction. Either the positive or the negative wiggle may
be shaded. The resulting PostScript code is written to
standard output.
files List one or more file-names. If no files are given,
pswiggle will read standard input.
-J Selects the map projection. Scale is UNIT/degree,
1:xxxxx, or width in UNIT (upper case modifier).
UNIT is cm, inch, or m, depending on the MEA
SURE_UNIT setting in .gmtdefaults, but this can be
overridden on the command line by appending the c,
i, or m to the scale/width value.
CYLINDRICAL PROJECTIONS:
-Jclon0/lat0/scale (Cassini)
-Jjlon0/scale (Miller)
-Jmscale (Mercator - Greenwich and Equator as ori
gin)
-Jmlon0/lat0/scale (Mercator - Give meridian and
standard parallel)
-Joalon0/lat0/azimuth/scale (Oblique Mercator -
point and azimuth)
-Joblon0/lat0/lon1/lat1/scale (Oblique Mercator -
two points)
-Joclon0/lat0/lonp/latp/scale (Oblique Mercator -
point and pole)
-Jqlon0/scale (Equidistant Cylindrical Projection
(Plate Carree))
-Jtlon0/scale (TM - Transverse Mercator, with Equa
tor as y = 0)
-Juzone/scale (UTM - Universal Transverse Mercator)
-Jylon0/lats/scale (Basic Cylindrical Projection)
AZIMUTHAL PROJECTIONS:
-Jalon0/lat0/scale (Lambert).
-Jelon0/lat0/scale (Equidistant).
-Jflon0/lat0/horizon/scale (Gnomonic).
-Jglon0/lat0/scale (Orthographic).
-Jslon0/lat0/[slat/]scale (General Stereographic)
CONIC PROJECTIONS:
-Jblon0/lat0/lat1/lat2/scale (Albers)
-Jdlon0/lat0/lat1/lat2/scale (Equidistant)
-Jllon0/lat0/lat1/lat2/scale (Lambert)
MISCELLANEOUS PROJECTIONS:
-Jhlon0/scale (Hammer)
-Jilon0/scale (Sinusoidal)
-Jk[f|s]lon0/scale (Eckert IV (f) and VI (s))
-Jnlon0/scale (Robinson)
-Jrlon0/scale (Winkel Tripel)
-Jvlon0/scale (Van der Grinten)
-Jwlon0/scale (Mollweide)
NON-GEOGRAPHICAL PROJECTIONS:
-Jp[a]scale[/origin] (polar (theta,r) coordinates,
optional a for azimuths and offset theta [0])
-Jxx-scale[l|ppow][/y-scale[l|ppow]] (Linear, log,
and power scaling)
More details can be found in the psbasemap man
pages.
-R west, east, south, and north specify the Region of
interest. To specify boundaries in degrees and min
utes [and seconds], use the dd:mm[:ss] format.
Append r if lower left and upper right map coordi
nates are given instead of wesn.
-Z Gives anomaly scale in data-units/distance-unit.
OPTIONS
No space between the option flag and the associated argu
ments.
-A Sets the preferred positive azimuth. Positive wig
gles will "gravitate" towards that direction.
-B Sets map boundary tickmark intervals. See psbasemap
[0].
-D Means there is a data gap if 2 consecutive points
are more than gap distance units apart. For longi
tude/latitude data gap is in km, else it is in the
user's units.'
-E Sets the viewpoint's azimuth and elevation
[180/90]'
-G Set fill of positive wiggles. [Default is black]
Specify the shade (0-255) or color (r/g/b), or
-Gpdpi/pattern, where pattern gives the number of
the built-in pattern (1-90) OR the name of a Sun
1-, 8-, or 24-bit raster file. dpi sets the reso
lution of the image. For 1-bit rasters: use -GP for
inverse video, or append :Fr/g/b[B[r/g/b]] to spec
ify fore- and background colors (use r/g/b = - for
transparency). See GMT Cookbook & Technical Refer
ence Appendix E for information on individual pat
terns.
-H Input file(s) has Header record(s). Number of
header records can be changed by editing your .gmt
defaults file. If used, GMT default is 1 header
record.
-I Set a fixed azimuth projection for wiggles [Default
uses track azimuth, but see -A].
-K More PostScript code will be appended later
[Default terminates the plot system].
-M Multiple segment file. Segments are separated by a
record whose first character is flag. [Default is
'>'].
-N Paint negative wiggles instead of positive
[Default].
-O Selects Overlay plot mode [Default initializes a
new plot system].
-P Selects Portrait plotting mode [GMT Default is
Landscape, see gmtdefaults to change this].
-S Draws a simple vertical scale centered on
lon0/lat0. Use -Sx to specify cartesian coordinates
instead. length is in z units, append unit name
for labeling
-T Draw track [Default is no track]. Append pen
-U Draw Unix System time stamp on plot. User may spec
ify where the lower left corner of the stamp should
fall on the page relative to lower left corner of
plot. Optionally, append a label, or c (which will
plot the command string.). The GMT parameters
UNIX_TIME and UNIX_TIME_POS can affect the appear
ance; see the gmtdefaults man page for details.
-V Selects verbose mode, which will send progress
reports to stderr [Default runs "silently"].
-W Draw wiggle outline [Default is no outline]. Append
pen attributes to use [Defaults: width = 1, color =
0/0/0, texture = solid].
-X -Y Shift origin of plot by (x-shift,y-shift). Prepend
a for absolute coordinates; the default (r) will
reset plot origin.
-: Toggles between (longitude,latitude) and (lati
tude,longitude) input/output. [Default is (longi
tude,latitude)]. Applies to geographic coordinates
only.
-c Specifies the number of plot copies. [Default is 1]
-bi Selects binary input. Append s for single precision
[Default is double]. Append n for the number of
columns in the binary file(s). [Default is 3 input
columns].
EXAMPLES
To plot the magnetic anomaly stored in the file track.xym
along track @ 1000 nTesla/cm (after removing a mean value
of 32000 Tesla), using a 15-cm-wide Polar Stereographic
map ticked every 5 degrees in Portrait mode, with positive
anomalies in red on a blue track of width 0.25 points, try
pswiggle track.xym -R-20/10/-80/-60 -JS0/90/15c -Z1000 -B5
-P -G255/0/0 -T0.25p/0/0/255 -S1000 -V > track_xym.ps
BUGS
Sometimes the (x,y) coordinates are not printed with
enough significant digits, so the local perpendicular to
the track swings around a lot. To see if this is the prob
lem, you should do this:
awk '{ if (NR > 1) print atan2(y-$1, x-$2); y=$1; x=$2; }'
yourdata.xyz | more
(note that output is in radians; on some machines you need
gmtset D_FORMAT %.12lg
awk '{ print NR, $0 }' yourdata.xyz | filter1d -Fb5 -N4/0
> smoothed.xyz
and plot this data set instead.
SEE ALSO
gmt(l), filter1d(l), psbasemap(l), splitxyz(l)
Man(1) output converted with
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