1tide(1)                     General Commands Manual                    tide(1)
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NAME

6       tide - Harmonic tide clock and tide predictor (command line client)
7

SYNOPSIS

9       tide  [-b  ``YYYY-MM-DD  HH:MM'']  [-cf ``format-string''] [-ch pixels]
10       [-cw pixels]  [-dc  color]  [-Dc  color]  [-df  ``format-string'']  [-e
11       ``YYYY-MM-DD   HH:MM'']   [-ec   color]   [-el  y|n]  [-em  pSsMm]  [-f
12       c|h|i|l|p|t|v] [-fc color] [-fg color] [-ga aspect] [-gh  pixels]  [-gs
13       d|l|s]  [-gt  y|n]  [-gw  pixels] [-hf ``format-string''] [-in y|n] [-l
14       ``location name''] [-lb y|n] [-lw  pixels]  [-m  a|b|c|C|g|k|l|m|p|r|s]
15       [-mc  color] [-Mc color] [-ml [-]N.NN(ft|m|kt)] [-nc color] [-o ``file‐
16       name''] [-ou y|n] [-pb y|n] [-ph mm] [-pi days] [-pm mm] [-pw  mm]  [-s
17       ``HH:MM'']  [-tf  ``format-string'']  [-th  characters]  [-tl y|n] [-to
18       opacity] [-tw characters] [-u ft|m] [-v] [-z y|n]
19

DESCRIPTION

21       XTide is a package that provides tide and current predictions in a wide
22       variety  of formats. Graphs, text listings, and calendars can be gener‐
23       ated, or a tide clock can be provided on your desktop.
24
25       XTide can work with X-windows, plain text terminals, or the  web.  This
26       is accomplished with three separate programs: the interactive interface
27       (xtide), the non-interactive or command line interface (tide), and  the
28       web interface (xttpd).
29
30       tide  is  the  non-interactive  command line client for XTide 2.  For a
31       complete  discussion,  please  see   the   verbose   documentation   at
32       https://flaterco.com/xtide/.
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CONFIGURATION

35       Unless  a  configuration file /etc/xtide.conf is supplied, you must set
36       the environment variable HFILE_PATH to point  to  the  harmonics  files
37       that should have been installed along with the xtide program.  Example:
38              export HFILE_PATH=/usr/local/share/xtide/harmonics.tcd
39       If  a  configuration file is used, the first line should consist of the
40       colon-separated list of harmonics files (e.g. the HFILE_PATH line above
41       without the "export HFILE_PATH=" part).  The environment variable takes
42       precedence over the configuration file.
43
44       Set the environment variable XTIDE_DEFAULT_LOCATION to the name of your
45       favorite place if you want to skip the location-choosing step.
46

OPTIONS

48       -b ``YYYY-MM-DD HH:MM''
49              Specify  the  begin  (start)  time for predictions using the ISO
50              8601 compliant format YYYY-MM-DD HH:MM, where hours  range  from
51              00 to 23.  The timestamp is in the local time zone for the loca‐
52              tion, or in UTC if the -z setting is engaged.  If clock mode  is
53              selected or if no -b is supplied, the current time will be used.
54
55       -cf ``format-string''
56              strftime(3)  style  format string for printing days in calendars
57              (default %a %d).
58
59       -ch pixels
60              Height for tide clocks (default 312 pixels).
61
62       -cw pixels
63              Width for tide clocks (default 84 pixels).
64
65       -dc color
66              Daytime background color in tide graphs (default SkyBlue).
67
68       -Dc color
69              Color of datum line in tide graphs (default white).
70
71       -df ``format-string''
72              strftime(3) style format  string  for  printing  dates  (default
73              %Y-%m-%d).  For calendars see -cf.
74
75       -e ``YYYY-MM-DD HH:MM''
76              Specify the end (stop) time for predictions in banner, calendar,
77              alt. calendar, medium rare, plain, raw, or stats mode.  Does not
78              apply  in  graph  and  clock  modes:  the effective end time for
79              graph and clock modes is entirely determined by the  start  time
80              (-b),  the  width  (-cw, -gw or -tw), and the aspect (-ga).  The
81              format and time zone are the same as for -b.  If no -e  is  sup‐
82              plied,  the  end  time  will be set to four days after the begin
83              time.
84
85       -ec color
86              Foreground in tide graphs during  outgoing  tide  (default  Sea‐
87              Green).
88
89       -el y|n
90              Select  whether  or  not to draw datum and middle-level lines in
91              tide graphs (default n).
92
93              The National Ocean Service (NOS) defines  both  Mean  Sea  Level
94              (MSL)  and Mean Tide Level (MTL) in terms of averages taken over
95              observations.  The middle-level line is drawn at the midpoint of
96              the  theoretical  tidal  range, which usually corresponds to the
97              mathematical mean level of the predictions.   This  approximates
98              both  MSL and MTL, but, strictly speaking, is equivalent to nei‐
99              ther.  Moreover,  subordinate  station  offsets  may  shift  the
100              actual  mean  so  that it no longer falls at the midpoint of the
101              tidal range.  The datum line is drawn at the zero level  of  the
102              predictions,  which  usually corresponds to the station's bench‐
103              mark, but this too can be  rendered  inaccurate  by  subordinate
104              station offsets.
105
106       -em pSsMm
107              Events  to suppress (p = phase of moon, S = sunrise, s = sunset,
108              M = moonrise, m = moonset), or x to suppress none.  E.g, to sup‐
109              press all sun and moon events, set eventmask to the value pSsMm.
110
111       -f c|h|i|l|p|t|v
112              Specify  the  output format as CSV, HTML, iCalendar, LaTeX, PNG,
113              text, or SVG.  The default is text.
114
115       -fc color
116              Foreground in tide graphs during incoming tide (default Blue).
117
118       -fg color
119              Color of text and other notations (default black).
120
121       -ga aspect
122              Aspect for tide graphs, clocks, and banners (default 1.0).  This
123              controls  not  the  width or height of the window but rather the
124              relative scaling of the X and Y axes in the  plot  of  the  tide
125              curve.
126
127       -gh pixels
128              Height for tide graphs (default 312 pixels).
129
130       -gs d|l|s
131              Style  of  graphs  and  clocks.   Valid  values:  d (default), l
132              (line), s (semitransparent).
133
134       -gt y|n
135              Select whether or not to label tenths of units  in  tide  graphs
136              (default n).
137
138       -gw pixels
139              Width for tide graphs (default 960 pixels).
140
141       -hf ``format-string''
142              strftime(3) style format string for printing hour labels on time
143              axis (default %l).
144
145       -in y|n
146              Select whether or not to  use  inferred  values  for  some  con‐
147              stituents (default n).  For expert use only.
148
149       -l ``location name''
150              Specify a location for tide predictions.  You get the first sta‐
151              tion where the name supplied with -l is a case-insensitive match
152              with the beginning (or the entirety) of the station's name.
153
154       -lb y|n
155              Select  whether or not calendar mode inserts a line break before
156              prediction values (default n).
157
158       -lw pixels
159              Width of line in graph styles l and s (default 2.5 pixels).
160
161       -m a|b|c|C|g|k|l|m|p|r|s
162              Specify mode to  be  about,  banner,  calendar,  alt.  calendar,
163              graph,  clock,  list,  medium  rare,  plain, raw, or stats.  The
164              default is plain.
165
166       -mc color
167              Color of mark line in graphs (default red).
168
169       -Mc color
170              Color of middle-level line in tide graphs (default yellow).
171
172       -ml [-]N.NN(ft|m|kt)
173              Specify the mark level to be used in predictions.   The  predic‐
174              tions  will  include  the  times when the tide level crosses the
175              mark.  Not supported in clock mode.  Example usage: -ml -0.25ft
176
177       -nc color
178              Nighttime background color in tide graphs (default DeepSkyBlue).
179
180       -o ``filename''
181              Redirect output to the specified file (appends).
182
183       -ou y|n
184              Select whether or not to print numbers with no ft/m/kt  (default
185              n).  Where  possible,  adds  a header line stating the units and
186              datum.
187
188       -pb y|n
189              Select whether or not calendar mode inserts  a  page  break  and
190              repeats  the  station  header  for each month in text, HTML, and
191              LaTeX formats (default y).
192
193       -ph mm Nominal length of paper in LaTeX output (default 420 mm).   This
194              need  not  match your actual paper; use "Shrink oversized pages"
195              in print options.
196
197       -pi days
198              Number of days of predictions to generate when no  end  time  is
199              specified (default 4).
200
201       -pm mm Nominal  width  of  top, bottom, left and right margins in LaTeX
202              output (default 10 mm).  Actual width will depend on print scal‐
203              ing.
204
205       -pw mm Nominal  width  of  paper in LaTeX output (default 297 mm). This
206              need not match your actual paper; use "Shrink  oversized  pages"
207              in print options.
208
209       -s ``HH:MM''
210              Specify  the  step  interval,  in  hours and minutes, for raw or
211              medium rare mode predictions.  The default is one hour.
212
213       -tf ``format-string''
214              strftime(3) style format  string  for  printing  times  (default
215              %l:%M %p %Z).
216
217       -th characters
218              Height of ASCII graphs and clocks (default 24 characters).
219
220       -tl y|n
221              Select  whether  or  not  to draw depth lines on top of the tide
222              graph (default n).
223
224       -to opacity
225              Opacity of the fill in graph style s (semitransparent)  (default
226              0.65).
227
228       -tw characters
229              Width of text format (default 79 characters).
230
231       -u ft|m
232              Preferred units of length (default no preference).
233
234       -v     Print version string and exit.
235
236       -z y|n Select  whether  or not to coerce all time zones to UTC (default
237              n).
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NOTES

240       If the environment variable TERM is set to vt100 or  vt102,  tide  will
241       take  it seriously and invoke the DEC Special Graphics character set in
242       text form output.
243

SEE ALSO

245       xtide(1), xttpd(8), https://flaterco.com/xtide/.
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250XTide 2                           2020-06-27                           tide(1)
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