1PSWIGGLE(1)                  Generic Mapping Tools                 PSWIGGLE(1)
2
3
4

NAME

6       pswiggle - Plot anomaly along track on a map
7

SYNOPSIS

9       pswiggle  xyz_files  -Jparameters  -Rwest/east/south/north[r] -Zscale [
10       -Aazimuth ]  [  -B[p|s]parameters  ]  [  -Ccenter  ]  [  -D[x]gap  ]  [
11       -Eazim/elev[+wlon/lat[/z]][+vx0/y0]  ]  [  -Gfill  ]  [ -H[i][nrec] ] [
12       -Jz|Zparameters ] [ -Ifix_az ] [ -K  ]  [  -N  ]  [  -O  ]  [  -P  ]  [
13       -S[x]lon0/lat0/length[/units]  ] [ -Tpen ] [ -U[just/dx/dy/][c|label] ]
14       [ -V ] [ -Wpen ] [ -X[a|c|r][x-shift[u]] ] [ -Y[a|c|r][y-shift[u]] ]  [
15       -ccopies ] [ -:[i|o] ] [ -bi[s|S|d|D[ncol]|c[var1/...]] ] [ -fcolinfo ]
16       [ -m[i|o][flag] ]
17

DESCRIPTION

19       pswiggle reads (x,y,z) triplets from  files  [or  standard  input]  and
20       plots  z  as  a  function of distance along track.  This means that two
21       consecutive (x,y) points define the local distance axis, and the  local
22       z  axis is then perpendicular to the distance axis.  The user may set a
23       preferred positive anomaly plot direction, and if the  positive  normal
24       is  outside the plus/minus 90 degree window around the preferred direc‐
25       tion, then 180 degrees are added to the direction.  Either the positive
26       or the negative wiggle may be shaded.  The resulting PostScript code is
27       written to standard output.
28
29       files  List one or more file-names. If no  files  are  given,  pswiggle
30              will read standard input.
31
32       -J     Selects  the  map  projection. Scale is UNIT/degree, 1:xxxxx, or
33              width in UNIT (upper case modifier).  UNIT is cm,  inch,  or  m,
34              depending on the MEASURE_UNIT setting in .gmtdefaults4, but this
35              can be overridden on the command line by appending c, i, or m to
36              the  scale/width  value.   When  central  meridian  is optional,
37              default is center of longitude  range  on  -R  option.   Default
38              standard  parallel  is  the equator.  For map height, max dimen‐
39              sion, or min dimension, append h, +, or - to the width,  respec‐
40              tively.
41              More details can be found in the psbasemap man pages.
42
43              CYLINDRICAL PROJECTIONS:
44
45              -Jclon0/lat0/scale (Cassini)
46              -Jcyl_stere/[lon0/[lat0/]]scale (Cylindrical Stereographic)
47              -Jj[lon0/]scale (Miller)
48              -Jm[lon0/[lat0/]]scale (Mercator)
49              -Jmlon0/lat0/scale (Mercator - Give meridian and standard paral‐
50              lel)
51              -Jo[a]lon0/lat0/azimuth/scale  (Oblique  Mercator  -  point  and
52              azimuth)
53              -Jo[b]lon0/lat0/lon1/lat1/scale (Oblique Mercator - two points)
54              -Joclon0/lat0/lonp/latp/scale  (Oblique  Mercator  -  point  and
55              pole)
56              -Jq[lon0/[lat0/]]scale (Cylindrical Equidistant)
57              -Jtlon0/[lat0/]scale (TM - Transverse Mercator)
58              -Juzone/scale (UTM - Universal Transverse Mercator)
59              -Jy[lon0/[lat0/]]scale (Cylindrical Equal-Area)
60
61              CONIC PROJECTIONS:
62
63              -Jblon0/lat0/lat1/lat2/scale (Albers)
64              -Jdlon0/lat0/lat1/lat2/scale (Conic Equidistant)
65              -Jllon0/lat0/lat1/lat2/scale (Lambert Conic Conformal)
66              -Jpoly/[lon0/[lat0/]]scale ((American) Polyconic)
67
68              AZIMUTHAL PROJECTIONS:
69
70              -Jalon0/lat0[/horizon]/scale (Lambert Azimuthal Equal-Area)
71              -Jelon0/lat0[/horizon]/scale (Azimuthal Equidistant)
72              -Jflon0/lat0[/horizon]/scale (Gnomonic)
73              -Jglon0/lat0[/horizon]/scale (Orthographic)
74              -Jglon0/lat0/altitude/azimuth/tilt/twist/Width/Height/scale
75              (General Perspective).
76              -Jslon0/lat0[/horizon]/scale (General Stereographic)
77
78              MISCELLANEOUS PROJECTIONS:
79
80              -Jh[lon0/]scale (Hammer)
81              -Ji[lon0/]scale (Sinusoidal)
82              -Jkf[lon0/]scale (Eckert IV)
83              -Jk[s][lon0/]scale (Eckert VI)
84              -Jn[lon0/]scale (Robinson)
85              -Jr[lon0/]scale (Winkel Tripel)
86              -Jv[lon0/]scale (Van der Grinten)
87              -Jw[lon0/]scale (Mollweide)
88
89              NON-GEOGRAPHICAL PROJECTIONS:
90
91              -Jp[a]scale[/origin][r|z] (Polar coordinates (theta,r))
92              -Jxx-scale[d|l|ppow|t|T][/y-scale[d|l|ppow|t|T]]  (Linear,  log,
93              and power scaling)
94
95       -R     xmin, xmax, ymin, and ymax specify the Region of interest.   For
96              geographic  regions,  these  limits  correspond  to  west, east,
97              south, and north and you may specify them in decimal degrees  or
98              in  [+-]dd:mm[:ss.xxx][W|E|S|N]  format.  Append r if lower left
99              and upper right map coordinates are given  instead  of  w/e/s/n.
100              The  two  shorthands  -Rg and -Rd stand for global domain (0/360
101              and -180/+180 in longitude respectively, with -90/+90  in  lati‐
102              tude).  Alternatively, specify the name of an existing grid file
103              and the -R settings (and grid spacing, if applicable) are copied
104              from  the  grid.   For  calendar time coordinates you may either
105              give (a) relative time (relative to the selected TIME_EPOCH  and
106              in  the  selected TIME_UNIT; append t to -JX|x), or (b) absolute
107              time of the form [date]T[clock] (append T to -JX|x).   At  least
108              one of date and clock must be present; the T is always required.
109              The date string must be of the form [-]yyyy[-mm[-dd]] (Gregorian
110              calendar) or yyyy[-Www[-d]] (ISO week calendar), while the clock
111              string must be of the form hh:mm:ss[.xxx].  The  use  of  delim‐
112              iters  and their type and positions must be exactly as indicated
113              (however, input, output and plot formats are  customizable;  see
114              gmtdefaults).
115
116       -Z     Gives anomaly scale in data-units/distance-unit.
117

OPTIONS

119       No space between the option flag and the associated arguments.
120
121       -A     Sets  the  preferred  positive  azimuth.   Positive wiggles will
122              "gravitate" towards that direction.
123
124       -B     Sets map boundary annotation and  tickmark  intervals;  see  the
125              psbasemap man page for all the details.
126
127       -C     Subtract center from the data set before plotting [0].
128
129       -D     Means  there is a data gap if 2 consecutive points are more than
130              gap distance units apart.  For geographic  map  projections  the
131              gap is assumed to be in km, else it is in the user's units.
132
133       -E     Sets  the  viewpoint's  azimuth  and  elevation (for perspective
134              view) [180/90].  For frames used for animation, you may want  to
135              append  +  to  fix  the center of your data domain (or specify a
136              particular world coordinate  point  with  +wlon0/lat[/z])  which
137              will  project  to  the  center of your page size (or specify the
138              coordinates of the projected veiw point with +vx0/y0).
139
140       -G     Set fill shade, color or pattern of positive wiggles [Default is
141              black] (See SPECIFYING FILL below).
142
143       -H     Input file(s) has header record(s).  If used, the default number
144              of header records is N_HEADER_RECS.  Use -Hi if only input  data
145              should  have  header  records  [Default  will  write  out header
146              records if the input data have  them].  Blank  lines  and  lines
147              starting with # are always skipped.
148
149       -I     Set  a  fixed azimuth projection for wiggles [Default uses track
150              azimuth, but see -A].
151
152       -K     More PostScript code will be appended later [Default  terminates
153              the plot system].
154
155       -N     Paint negative wiggles instead of positive [Default].
156
157       -O     Selects  Overlay  plot mode [Default initializes a new plot sys‐
158              tem].
159
160       -P     Selects Portrait plotting mode [Default is Landscape, see gmtde‐
161              faults to change this].
162
163       -S     Draws a simple vertical scale centered on lon0/lat0.  Use -Sx to
164              specify cartesian coordinates instead.  length is  in  z  units,
165              append unit name for labeling
166
167       -T     Draw track  [Default is no track].  Append pen attributes to use
168              [Defaults: width = 0.25p, color = black, texture = solid].  (See
169              SPECIFYING PENS below).
170
171       -U     Draw Unix System time stamp on plot.  By adding just/dx/dy/, the
172              user may specify the justification of the stamp  and  where  the
173              stamp  should  fall on the page relative to lower left corner of
174              the plot.  For example, BL/0/0 will align the lower left  corner
175              of  the  time  stamp  with  the  lower  left corner of the plot.
176              Optionally, append a label, or c (which will  plot  the  command
177              string.).   The  GMT  parameters  UNIX_TIME,  UNIX_TIME_POS, and
178              UNIX_TIME_FORMAT can affect the appearance; see the  gmtdefaults
179              man page for details.  The time string will be in the locale set
180              by the environment variable TZ (generally local time).
181
182       -V     Selects verbose mode, which will send progress reports to stderr
183              [Default runs "silently"].
184
185       -W     Draw  wiggle  outline   [Default  is  no  outline].   Append pen
186              attributes to use [Defaults: width = 0.25p, color = black,  tex‐
187              ture = solid].  (See SPECIFYING PENS below).
188
189       -X -Y  Shift  plot origin relative to the current origin by (x-shift,y-
190              shift) and optionally append the length unit (c, i, m, p).   You
191              can  prepend a to shift the origin back to the original position
192              after plotting, or prepend  r [Default]  to  reset  the  current
193              origin  to the new location.  If -O is used then the default (x-
194              shift,y-shift) is (0,0), otherwise it is (r1i, r1i)  or  (r2.5c,
195              r2.5c).  Alternatively, give c to align the center coordinate (x
196              or y) of the plot with the center of the page based  on  current
197              page size.
198
199       -:     Toggles  between  (longitude,latitude)  and (latitude,longitude)
200              input and/or output.  [Default is (longitude,latitude)].  Append
201              i  to  select  input  only or o to select output only.  [Default
202              affects both].
203
204       -bi    Selects binary input.  Append s for single precision [Default is
205              d  (double)].   Uppercase  S  or  D  will  force  byte-swapping.
206              Optionally, append ncol, the number of columns  in  your  binary
207              input  file if it exceeds the columns needed by the program.  Or
208              append c  if  the  input  file  is  netCDF.  Optionally,  append
209              var1/var2/...  to specify the variables to be read.  [Default is
210              3 input columns].
211
212       -c     Specifies the number of plot copies. [Default is 1].
213
214       -f     Special formatting of input and/or output columns (time or  geo‐
215              graphical  data).   Specify  i  or  o to make this apply only to
216              input or output [Default applies to both].   Give  one  or  more
217              columns (or column ranges) separated by commas.  Append T (abso‐
218              lute calendar time), t (relative time in chosen TIME_UNIT  since
219              TIME_EPOCH),  x (longitude), y (latitude), or f (floating point)
220              to each column or column range item.  Shorthand  -f[i|o]g  means
221              -f[i|o]0x,1y (geographic coordinates).
222
223       -m     Multiple  segment  file(s).  Segments are separated by a special
224              record.  For ASCII  files  the  first  character  must  be  flag
225              [Default  is  '>'].  For binary files all fields must be NaN and
226              -b must set the number of output columns explicitly.  By default
227              the  -m  setting  applies to both input and output.  Use -mi and
228              -mo to give separate settings to input and output.
229
230   SPECIFYING PENS
231       pen    The attributes of lines and symbol outlines as defined by pen is
232              a  comma  delimetered  list of width, color and texture, each of
233              which is optional.  width can be indicated as a measure (points,
234              centimeters, inches) or as faint, thin[ner|nest], thick[er|est],
235              fat[ter|test], or obese.  color specifies a gray shade or  color
236              (see  SPECIFYING  COLOR  below).   texture  is  a combination of
237              dashes `-' and dots `.'.
238
239   SPECIFYING FILL
240       fill   The attribute fill specifies the solid shade or solid color (see
241              SPECIFYING  COLOR  below)  or the pattern used for filling poly‐
242              gons.  Patterns are specified  as  pdpi/pattern,  where  pattern
243              gives the number of the built-in pattern (1-90) or the name of a
244              Sun 1-, 8-, or 24-bit raster file. The dpi sets  the  resolution
245              of  the  image.  For 1-bit rasters: use Pdpi/pattern for inverse
246              video, or append :Fcolor[B[color]] to specify  fore-  and  back‐
247              ground  colors  (use color = - for transparency).  See GMT Cook‐
248              book & Technical Reference Appendix E for information  on  indi‐
249              vidual patterns.
250
251   SPECIFYING COLOR
252       color  The  color  of  lines,  areas and patterns can be specified by a
253              valid color name; by a gray shade (in the  range  0-255);  by  a
254              decimal  color  code  (r/g/b, each in range 0-255; h-s-v, ranges
255              0-360, 0-1, 0-1; or c/m/y/k, each in range 0-1); or by  a  hexa‐
256              decimal  color code (#rrggbb, as used in HTML).  See the gmtcol‐
257              ors manpage for more information and a full list of color names.
258

EXAMPLES

260       To plot the magnetic anomaly stored in the file track.xym along track @
261       1000  nTesla/cm  (after removing a mean value of 32000 nTesla), using a
262       15-cm-wide Polar Stereographic map ticked every 5 degrees  in  Portrait
263       mode,  with  positive  anomalies  in  red on a blue track of width 0.25
264       points, use
265
266       pswiggle track.xym -R-20/10/-80/-60 -JS0/90/15c -Z1000 -B5  -C32000  -P
267       -Gred -T0.25p,blue -S1000 -V > track_xym.ps
268

BUGS

270       Sometimes the (x,y) coordinates are not printed with enough significant
271       digits, so the local perpendicular to the track swings  around  a  lot.
272       To see if this is the problem, you should do this:
273
274       awk '{ if (NR > 1) print atan2(y-$1, x-$2); y=$1; x=$2; }' yourdata.xyz
275       | more
276
277       (note that output is in radians; on some machines you need "nawk" to do
278       this).  Then if these numbers jump around a lot, you may do this:
279
280       awk  '{  print  NR,  $0  }' yourdata.xyz | filter1d -Fb5 -N4/0 --D_FOR‐
281       MAT=value > smoothed.xyz
282
283       and plot this data set instead.
284

SEE ALSO

286       GMT(1), gmtcolors(5), filter1d(1), psbasemap(1), splitxyz(1)
287
288
289
290GMT 4.5.6                         10 Mar 2011                      PSWIGGLE(1)
Impressum