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Morning in OC

Modes

This page provides an overview of the kinds of things that XTide can do.  How to do them will be explained in the next section.

Graph mode

San Francisco graph

Graph mode gives you a plot of the water level (or water velocity, in the case of currents) versus time.  The times of high and low tide (or max flood and max ebb) are printed across the top.  Sunrise and sunset are denoted with different background colors; moonrise, moonset, and moon phases are shown along the bottom.  A + mark on the graph indicates the conditions at the time that the graph was generated.

For currents, the times of slack water are also shown along the bottom.  If necessary, crowding of the bottom caption line can be relieved in several ways (see Advanced usage).

Default current graph

Clock mode

Clock mode  

Clock mode is similar to graph mode, but the captions are different and the window is automatically updated once a minute to show the latest conditions.  From top to bottom, the window shows the current time, the next high tide (or maximum flood), the predicted height or velocity for the current time (shown with a +), and the next low tide (or maximum ebb).  Other events like slack water and moon phases do not appear.

Classic analog tide clock If a tide clock is iconified using an ancient window manager like twm, the icon will appear as a classic round tide clock that gives a vague idea of where you are in the tide cycle.  Unfortunately, this feature is not accessible at all from newer windows environments that disregard the old icon protocol.  Even some of the old window managers had trouble with it; they would crash, or the icon would fail to update.

Plain mode

Plain text listing of events, no foo-foo.

San Francisco, California
37.8067░ N, 122.4650░ W

2003-02-13  2:17 PM PST   Moonrise
2003-02-13  3:25 PM PST  -0.32 feet  Low Tide
2003-02-13  5:46 PM PST   Sunset
2003-02-13 10:49 PM PST   4.64 feet  High Tide
2003-02-14  3:05 AM PST   3.16 feet  Low Tide
2003-02-14  5:44 AM PST   Moonset
2003-02-14  7:01 AM PST   Sunrise
2003-02-14  9:02 AM PST   6.27 feet  High Tide

Calendar mode

Calendar mode arranges most of the information available in text mode into a commonly used tabular layout.

January 2007

DayHigh


Low
High


Low
High

PhaseSunriseSunsetMoonriseMoonset
Mon 013:48 AM EST 0.17 m9:58 AM EST −0.14 m5:07 PM EST 0.43 m7:26 AM EST4:53 PM EST2:49 PM EST5:49 AM EST
Tue 0212:25 AM EST −0.01 m4:46 AM EST 0.16 m10:52 AM EST −0.14 m6:00 PM EST 0.42 m7:26 AM EST4:54 PM EST3:48 PM EST6:54 AM EST
Wed 031:15 AM EST −0.01 m5:40 AM EST 0.17 m11:45 AM EST −0.14 m6:50 PM EST 0.41 mFull Moon7:26 AM EST4:55 PM EST4:54 PM EST7:49 AM EST
Thu 042:00 AM EST −0.01 m6:32 AM EST 0.18 m12:37 PM EST −0.13 m7:37 PM EST 0.39 m7:26 AM EST4:56 PM EST6:03 PM EST8:34 AM EST
Fri 052:42 AM EST −0.00 m7:20 AM EST 0.19 m1:28 PM EST −0.12 m8:21 PM EST 0.37 m7:26 AM EST4:57 PM EST7:10 PM EST9:09 AM EST
Sat 063:20 AM EST −0.00 m8:08 AM EST 0.20 m2:16 PM EST −0.10 m9:02 PM EST 0.35 m7:26 AM EST4:58 PM EST8:15 PM EST9:37 AM EST
Sun 073:56 AM EST −0.00 m8:56 AM EST 0.21 m3:04 PM EST −0.08 m9:40 PM EST 0.32 m7:26 AM EST4:59 PM EST9:17 PM EST10:02 AM EST

"Alt" calendar mode arranges the information into a traditional weekly calendar layout.

Sun 07Mon 08Tue 09Wed 10Thu 11Fri 12Sat 13
Low Tide −0.00 m
3:56 AM EST
Sunrise
7:26 AM EST
High Tide 0.21 m
8:56 AM EST
Moonset
10:02 AM EST
Low Tide −0.08 m
3:04 PM EST
Sunset
4:59 PM EST
Moonrise
9:17 PM EST
High Tide 0.32 m
9:40 PM EST
Low Tide −0.01 m
4:28 AM EST
Sunrise
7:26 AM EST
High Tide 0.22 m
9:46 AM EST
Moonset
10:23 AM EST
Low Tide −0.05 m
3:53 PM EST
Sunset
5:00 PM EST
High Tide 0.30 m
10:16 PM EST
Moonrise
10:17 PM EST
Low Tide −0.02 m
4:58 AM EST
Sunrise
7:26 AM EST
High Tide 0.22 m
10:39 AM EST
Moonset
10:43 AM EST
Low Tide −0.01 m
4:46 PM EST
Sunset
5:00 PM EST
High Tide 0.27 m
10:51 PM EST
Moonrise
11:16 PM EST
Low Tide −0.04 m
5:28 AM EST
Sunrise
7:25 AM EST
Moonset
11:03 AM EST
High Tide 0.24 m
11:35 AM EST
Sunset
5:01 PM EST
Low Tide 0.03 m
5:49 PM EST
High Tide 0.24 m
11:27 PM EST
Moonrise
12:14 AM EST
Low Tide −0.06 m
6:00 AM EST
Sunrise
7:25 AM EST
Last Quarter
7:45 AM EST
Moonset
11:23 AM EST
High Tide 0.25 m
12:32 PM EST
Sunset
5:02 PM EST
Low Tide 0.05 m
7:01 PM EST
High Tide 0.21 m
12:07 AM EST
Moonrise
1:15 AM EST
Low Tide −0.08 m
6:35 AM EST
Sunrise
7:25 AM EST
Moonset
11:46 AM EST
High Tide 0.28 m
1:29 PM EST
Sunset
5:04 PM EST
Low Tide 0.06 m
8:18 PM EST
High Tide 0.18 m
12:52 AM EST
Moonrise
2:17 AM EST
Low Tide −0.09 m
7:15 AM EST
Sunrise
7:25 AM EST
Moonset
12:14 PM EST
High Tide 0.30 m
2:22 PM EST
Sunset
5:05 PM EST
Low Tide 0.06 m
9:30 PM EST

Calendar mode is not available from the interactive client.

Banner mode

Banner mode is a specialization of graph mode for output on old tractor feed dot matrix or line printers that use continuous reams of paper.  Also useful as a workaround if your printing application does stupid things with color graphs.  The graph is turned sideways and the aspect ratio is adjusted for Pica type.  This mode is only available in the command line client.

San Francisco, San Francisco Bay, California
37.8067░ N, 122.4650░ W

********-*****-*******************иииииииииииииииииииииииииииииииииииииииииииии
********2*****1*****0*****1*****2иииии3иииии4иииии5иииии6иииии7иииии82012-02-20
-4****** ***** ***** ***** ***** иииии иииии иииии иииии иииии иииии4:00 AM PST
********f*****f*****f*****f*****fиииииfиииииfиииииfиииииfиииииfиииииfииииииииии
********t*****t*****t*****t*****t*ииииtиииииtиииииtиииииtиииииtиииииtииииииииии
-5********************************иииииииииииииииииииииииииииииииииииииииииииии
****Moonrise***********************+ии|иииии|иииии|иииии|иииии|иииии|ииииииииии
-***5:53 AM PST**********************и|иииии|иииии|иииии|иииии|иииии|ииииииииии
-6************************************|иииии|иииии|иииии|иииии|иииии|ииииииииии
****************************************ииии|иииии|иииии|иииии|иииии|ииииииииии
******************************************  |     |     |     |     |          
-7******************************************|     |     |     |     |          
**********************************************    |     |     |     |          
************************************************  |     |     |     |          
-8************************************************|     |     |     |          
****************************************************    |     |     |          
******************************************************  |     |     |          
-9***************************************************** |     |     |          
*********************************************************     |     |          
*********************************************************     |     |2012-02-20
-10*******************************************************    |    10:08 AM PST
**********************************************************    |     |          
**********************************************************    |     |          
-11******************************************************     |     |          
********************************************************|     |     |          
******************************************************  |     |     |          
-12*************************************************    |     |     |          
************************************************* |     |     |     |          
**********************************************    |     |     |     |          
-1***************************************** |     |     |     |     |          
****************************************    |     |     |     |     |          
************************************  |     |     |     |     |     |          
-2*******************************     |     |     |     |     |     |          
******************************  |     |     |     |     |     |     |          
***************************     |     |     |     |     |     |     |          
-3*********************** |     |     |     |     |     |     |     |          
***********************   |     |     |     |     |     |     |     |          

Stats mode

Stats mode is mainly for finding the highest high tide and lowest low tide within some period of time.  However, it also provides an estimation of the Mean Lower Low Water datum based on the generated predictions.  In cases where an authoritative benchmark for a station is not available, this can be used to derive a reasonable approximation.  If the datum for the station has already been set to MLLW (as it should have been, for all U.S. stations) then the estimated value should be close to zero.

Stats mode is only available in the command line client.

Bar Harbor, Frenchman Bay, Maine
44.3917░ N, 68.2050░ W

Estimated upper bound:  14.05 feet
Estimated lower bound:  -2.71 feet
Mean, assuming symmetry:   5.67 feet

Searched interval from 2007-01-01 12:00 AM EST to 2008-01-01 12:00 AM EST
Maximum was  13.44 feet at 2007-11-25 10:31 AM EST
Minimum was  -2.05 feet at 2007-04-18  5:53 AM EDT
Mean of maxima and minima was   5.67 feet
Estimated MLLW:   0.15 feet

CPU time used:  0.280000 s

Raw mode

Raw mode is for getting machine-readable output that can be fed into other Unix programs.  The first column is a Unix time_t timestamp (seconds since 1970-01-01 00:00Z); the second column is tide heights in whatever units were selected for the location.

896624777 0.180580
896628377 1.271889
896631977 3.463100
896635577 6.084148
896639177 8.402840
896642777 9.943272
896646377 10.421064
896649977 9.672793
896653577 7.856022
896657177 5.543402
896660777 3.413487
896664377 1.926805
896667977 1.371479

Medium rare mode

Medium rare mode is just like raw mode except that the timestamps are "cooked" according to the date and time format settings that are in effect.

2002-02-06  4:56 PM EST 2.054437
2002-02-06  5:56 PM EST 1.573781
2002-02-06  6:56 PM EST 1.086896
2002-02-06  7:56 PM EST 0.656111
2002-02-06  8:56 PM EST 0.224729
2002-02-06  9:56 PM EST -0.161049
2002-02-06 10:56 PM EST -0.265521
2002-02-06 11:56 PM EST 0.077530

List mode

List mode does not provide tide predictions at all.  It is simply a way to get the list of supported locations from the command line client.

The 'Type' column shows Ref for reference stations and Sub for subordinate stations.  You should care about the difference.

LocationType Coordinates
0.8 n.mi. above entrance, Alloway Creek, New JerseySub39.4967░ N, 75.5167░ W
130th Street, Hudson River, New YorkSub40.8167░ N, 73.9667░ W
2.5 miles above mouth, Little Satilla River, GeorgiaSub31.0583░ N, 81.4933░ W
2.5 n.mi. above entrance, Alloway Creek, New JerseySub39.5050░ N, 75.4833░ W
3 miles above A1A highway bridge, Loxahatchee River, FloridaSub26.9700░ N, 80.1267░ W
37th Avenue, Long Island City, East River, New York, New YorkSub40.7617░ N, 73.9467░ W

About mode

About mode does not provide tide predictions either.  Instead, it shows the metadata for a station ("About this station").

NameBar Harbor, Frenchman Bay, Maine
In file/home/dave/svnrepo/software/xtide/harmonics-dwf-20111230-free.tcd
Station ID contextNOS
Station ID8413320
Date imported2011-12-25
Coordinates44.3917░ N, 68.2050░ W
CountryU.S.A.
Time zone:America/New_York
Native unitsfeet
Sourcehttp://tidesandcurrents.noaa.gov/
RestrictionPublic domain
CommentsHarmonic constants from web snapshot taken 2011-12-11
Datum from benchmark sheet, publication date 2011-09-29
CreditProcessed by David Flater for XTide
http://www.flaterco.com/xtide/
Original nameBar Harbor, ME
StateME
TypeReference station, tide
Meridian0:00
DatumMean Lower Low Water
Confidence10

Formats

XTide can render output in eight different formats:  X-windows, HTML, LaTeX, iCalendar, PNG, CSV, SVG, or text.  The X-windows format is implicit in the interactive client and can't be selected explicitly.  The others can be selected in the non-interactive client and are invoked automatically by the interactive and web clients (e.g., when you save output to a file).

The currently supported combinations of mode and format are as follows:

Mode Legal forms
about text, HTML, X-windows
banner text
calendar text, HTML, LaTeX, iCalendar, CSV
alt. calendar text, HTML, LaTeX
clock text, PNG, SVG, X-windows
graph text, PNG, SVG, X-windows
list text, HTML
plain text, X-windows, CSV
raw text, X-windows, CSV
medium rare text, X-windows, CSV
stats text

The HTML and PNG formats are adequately demonstrated by the examples above in the Modes section.

Text format

Several of the preceding examples, like plain mode, were in text format.  Here is an example of graph mode using the text format:

иииииииииииииииииSan Francisco, San Francisco Bay, California            ииииии
-12иииии2003-02-13иииииииииииии2003-02-13                 2003-02-13     ииииии
 PSTииии2:18 AM PSTииииииииииии8:12 AM PST                3:25 PM PST    ииииии
ииииииииииииииииииииииииииииииии                                         ииииии
ииииииииииииииииииииииииииииииии                                         ииииии
ииииииииииииииииииииииииииииииии                                         ииииии
ииииииииииииииииииииииииииииииии                                         ииииии
2 mи---------------------------------------------------------------------------
иииииииииииииииииииииииииииии*************                               ииииии
ииииииииииииииииииииииииии******************                             ииииии
***иииииииииииииииииии************************                           ииииии
**********иииииии*******************************                         ииииии
1 m***********************************************-----------------------------
****************************************************                     иииии*
******************************************************                   иии***
********************************************************                 ******
**********************************************************            *********
0 m****************************************************************************
*******************************************************************************
*******************************************************************************
********************Moonset****************************Moonrise****************
******************4:51 AM PST*************************2:17 PM PST**************
1**12***1***2***3**4***5***6***7***8***9*10**11**12***1***2***3***4**5***6***7*
|**|||**|***|***|**|***|***|***|***|***|**|***|***|***|***||**|***|**|***|***|*

Calendar mode is kind of cramped in text format if you use all default settings, but it can be made to work by using a compact time format, setting a wider TTY width, and/or turning off sun and moon information.  These are settings that you can change with the control panel or command-line switches.  See Appendix C for related discussion.

Bar Harbor, Frenchman Bay, Maine
44.3917░ N, 68.2050░ W

                                   May 2006

Day    High   Low    High   Low    High   Phase  Sunris Sunset Moonri Moonse 
Mon 01 01:42  08:10  14:23  20:23                05:23  19:36  07:38         
Tue 02 02:32  09:02  15:16  21:16                05:22  19:37  08:38  00:32  
Wed 03 03:25  09:56  16:10  22:12                05:20  19:39  09:44  01:17  
Thu 04 04:21  10:52  17:07  23:12                05:19  19:40  10:51  01:52  
Fri 05 05:20  11:49  18:05                First  05:18  19:41  11:58  02:19  
Sat 06        00:13  06:20  12:45  19:01         05:16  19:42  13:03  02:40  
Sun 07        01:11  07:18  13:38  19:52         05:15  19:44  14:07  02:59  
Mon 08        02:06  08:12  14:26  20:39         05:14  19:45  15:10  03:15  
Tue 09        02:55  09:01  15:10  21:21         05:12  19:46  16:14  03:31  
Wed 10        03:39  09:46  15:51  21:59         05:11  19:47  17:19  03:47  
Thu 11        04:21  10:27  16:28  22:36         05:10  19:48  18:27  04:05  
Fri 12        04:59  11:06  17:05  23:11         05:09  19:49  19:38  04:26  
Sat 13        05:36  11:45  17:41  23:48  Full M 05:07  19:51  20:51  04:52  
Sun 14        06:15  12:24  18:19                05:06  19:52  22:02  05:26  
Mon 15 00:26  06:55  13:05  18:59                05:05  19:53  23:07  06:11  
Tue 16 01:08  07:38  13:49  19:44                05:04  19:54         07:08  
Wed 17 01:55  08:25  14:38  20:35                05:03  19:55  00:02  08:17  
Thu 18 02:46  09:18  15:32  21:32                05:02  19:56  00:45  09:34  
Fri 19 03:43  10:14  16:30  22:34                05:01  19:57  01:19  10:53  
Sat 20 04:45  11:13  17:30  23:40         Last Q 05:00  19:58  01:46  12:12  
Sun 21 05:50  12:14  18:31                       04:59  19:59  02:08  13:30  
Mon 22        00:46  06:56  13:14  19:31         04:58  20:00  02:29  14:47  
Tue 23        01:50  07:59  14:12  20:27         04:57  20:01  02:49  16:05  
Wed 24        02:49  08:59  15:07  21:21         04:56  20:02  03:10  17:23  
Thu 25        03:45  09:56  15:59  22:12         04:56  20:03  03:34  18:43  
Fri 26        04:38  10:49  16:49  23:00         04:55  20:04  04:03  20:01  
Sat 27        05:28  11:39  17:38  23:48  New Mo 04:54  20:05  04:40  21:15  
Sun 28        06:16  12:27  18:25                04:53  20:06  05:26  22:18  
Mon 29 00:34  07:03  13:15  19:13                04:53  20:07  06:23  23:09  
Tue 30 01:21  07:51  14:03  20:01                04:52  20:08  07:27  23:49  
Wed 31 02:09  08:38  14:51  20:50                04:52  20:09  08:35         

SVG format

XTide can produce output in the Scalable Vector Graphics (SVG) format for graph and clock modes.  Graphs in SVG format ought to look better in a web browser than graphs in PNG format, but unfortunately, fonts.  Moreover, font metrics.

If your browser supports SVG, an SVG-formatted graph might appear here:

LaTeX format

Running LaTeX formatted output through pdflatex yields a PDF that looks approximately like this.  See Appendix C for hints on obtaining the best results.

iCalendar format

The iCalendar format yields an .ics file that can be imported by standards-compliant calendar tools to put tide events on your schedule.  It is only useful in calendar mode.

CSV format

CSV stands for Comma-Separated Values, a.k.a. comma-delimited.  This rigid format is useful for importing XTide output into database and spreadsheet applications with fixed columns.  Commas that are part of field values are replaced by the pipe character (|).

Washington| D.C.,2004-03-04,3:40 PM EST,,Moonrise
Washington| D.C.,2004-03-04,6:04 PM EST,,Sunset
Washington| D.C.,2004-03-04,6:23 PM EST,2.75 ft,High Tide
Washington| D.C.,2004-03-05,1:30 AM EST,0.21 ft,Low Tide

In calendar mode, the columns in CSV format are:  location name, date, five reps of (max time, max value), five reps of (min time, min value), ten reps of slack time, sunrise, sunset, moonrise, moonset.  The number of columns allocated is controlled by the compile-time constants numMaxMin and numRiseSet in CalendarFormC.cc.  Events exceeding the number of columns available are discarded with a warning.  Moon phases and mark level crossings are just discarded.

The use of compile-time constants instead of dynamically adjusted values is intentional, since whatever application is reading the CSV output needs the interpretation of columns to be predictable.  However, the default configuration allowing one column for rise and set events is not always adequate.  Yes!  You can have two sunsets in one day, and you don't even need Daylight Savings Time to do it:

Isla Neny, Antarctica
68.2000░ S, 67.0000░ W

2001-01-24 12:03 AM ARST   Sunset
2001-01-24  3:17 AM ARST   Sunrise
2001-01-24 11:57 PM ARST   Sunset

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