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.TH varnames 5 "CODAS Utilities" "GFI"
.tr \&
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.de DS
..
.de DE
..
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.ie \\n(ll>0 \{\
.ie \\n(bi=1 \{\
.nr bi 0
.if \\n(t\\n(ll=0 \{.IP \\(bu\}
.if \\n(t\\n(ll=1 \{.IP \\n+(e\\n(el.\}
.\}
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.\}
..
.SH NAME

.Pp
\fBVariable Names\fP - Convention for specifying CODAS variables

.SH DESCRIPTION

.Pp
This manual page describes the syntax for specifying CODAS
database variable names within control files. These are required by
some utilities that access data regardless of the database content.
.Pp
Variables must be specified by the name they have in the database.
They must also be present in it. The name is case sensitive. The
list of available names for a database can be displayed with
\fBshowdb\fP. Additional variable names which are not listed in
the database are:

.nr ll +1
.nr t\n(ll 2
.if \n(ll>1 .RS
.IP "\fBTIME\fP"
.nr bi 1
.Pp
To access the profile time.

.IP "\fBPOSITION\fP"
.nr bi 1
.Pp
To access profile position. The returned value will be a two
element array with both longitude and latitude values.

.IP "\fBLONGITUDE\fP"
.nr bi 1
.Pp
To access profile longitude, only.

.IP "\fBLATITUDE\fP"
.nr bi 1
.Pp
To access profile latitude, only.

.if \n(ll>1 .RE
.nr ll -1


.Pp
Note that the names that can be used depend firstly on the producer
definition file used to create the CODAS database.
.Pp
It is not possible to access a whole structure, however each of its
element can be specified. The syntax is similar to the C
programming language:

.br
.po 0.75i
.ll 6.0i
.nr LL 6.0i
.LP
\fISTRUCTURE_NAME\fP\fB.\fP\fIelement_name\fP

.br
.po 0.25i
.ll 7.0i
.nr LL 7.0i
.LP

Access is limited to one structure level, i.e. if a structure
element is a structure itself, you cannot access its values.

.SH EXAMPLE

.Pp
The following examples assume that the CODAS database to access has
been created together with a producer definition file containing the
following lines:

.DS
.sp
.ft RR
.nf
...

PROFILE_VAR    8  SHORT     U                    0       1.E-3   m/s
PROFILE_VAR    9  SHORT     V                    0       1.E-3   m/s
PROFILE_VAR   54  SHORT     W                    0       1.E-3   m/s
PROFILE_VAR   68  STRUCT    NAVIGATION           0       1       none
PROFILE_VAR   69  STRUCT    BOTTOM_TRACK         0       1       none
...

DEFINE_STRUCT  BOTTOM_TRACK  3
ELEM         1  FLOAT     u                                    m/s
ELEM         1  FLOAT     v                                    m/s
ELEM         1  FLOAT     depth                                m

...

DEFINE_STRUCT  NAVIGATION 4
ELEM         1  DOUBLE   latitude                             deg
ELEM         1  DOUBLE   longitude                            deg
ELEM         1  DOUBLE   speed                                knots
ELEM         1  DOUBLE   course                               deg

..

.DE
.fi
.ec
.ft P
.sp


.nr bi 1
.Pp
To access the velocities of an ADCP database, use \fBU\fP,
\fBV\fP and \fBW\fP.

.nr bi 1
.Pp
To access the percent good and spectral width of an ADCP
database, use \fBPERCENT_GOOD\fP and \fBSPECTRAL_WIDTH\fP.

.nr bi 1
.Pp
To access the ship's speed from the navigation, use
\fBNAVIGATION.speed\fP.

.nr bi 1
.Pp
To access the bottom tracking velocities, use
\fBBOTTOM_TRACK.u\fP and \fBBOTTOM_TRACK.v\fP.


.SH AUTHOR

.Pp
Manual page written by Pierre Jaccard, Geophysical Institute,
University of Bergen, 1999.