.if n .ds Q \&"
.if t .ds Q ``
.if n .ds U \&"
.if t .ds U ''
.TH isdef 3m "CODAS Utilities" "GFI"
.tr \&
.nr bi 0
.nr ll 0
.nr el 0
.de DS
..
.de DE
..
.de Pp
.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.\}
.\}
.el .sp
.\}
.el \{\
.ie \\nh=1 \{\
.LP
.nr h 0
.\}
.el .PP
.\}
..
.SH NAME

.Pp
\fBisdef\fP - Check if a variable is defined

.SH SYNOPSIS

.Pp
\fIa\fP = \fBisdef\fP(\fIw\fP)

.SH DESCRIPTION

.Pp
This function checks if a variable is defined. With higher version of
Matlab, it has become obsolete, as one can use the Matlab function
\fBexist\fP.
.SH PARAMETERS

.Pp
.nr ll +1
.nr t\n(ll 2
.if \n(ll>1 .RS
.IP "\fBw\fP  "
.nr bi 1
.Pp
The output of Matlab function \fBwho\fP.
.Pp
.IP "\fBvar\fP  "
.nr bi 1
.Pp
A string containing the variable name.
.Pp
.if \n(ll>1 .RE
.nr ll -1
.SH RETURNS

.Pp
.nr ll +1
.nr t\n(ll 2
.if \n(ll>1 .RS
.IP "\fBa\fP  "
.nr bi 1
.Pp
An array with 1 if the corresponding variable is defined,0
otherwise.
.Pp
.if \n(ll>1 .RE
.nr ll -1
.SH AUTHORS

.Pp
Pierre Jaccard, Geophysical Institute, University of Bergen, 1999