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<html>
<head>
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<title>ploticus: functions</title>
<body bgcolor=D0D0EE vlink=0000FF>
<br>
<br>
<center>
<table cellpadding=2 bgcolor=FFFFFF width=550 ><tr>
<td>
  <table cellpadding=2 width=550><tr>
  <td><br><h2>FUNCTIONS</h2></td>
  <td align=right>
  <small>
  <a href="../doc/Welcome.html"><img src="../doc/ploticus.gif" border=0></a><br>
  <a href="../doc/Welcome.html">Welcome</a> &nbsp; &nbsp;
  <a href="../gallery/index.html">Gallery</a> &nbsp; &nbsp;
  <a href="../doc/Contents.html">Handbook</a> 
  <td></tr></table>
</td></tr>
<td>
<br>
<br>

<title>Manual page for FUNCTIONS(PL)</title>
</head>
<body>

<p>
Categories of available functions:
<p>
<a href="functions.html#ploticus">
 plotting
</a>
<br>
<a href="functions.html#arithmetic">
 arithmetic
</a>
<br>
<a href="functions.html#strings">
 strings
</a>
<br>
<a href="functions.html#commalists">
 commalists
</a>
<br>
<a href="shell.html">
 shell
</a>
<br>
<a href="sql.html">
 sql
</a>
<br>
<a href="functions.html#dates">
 dates
</a>
<br>
<a href="functions.html#times">
 times
</a>
<br>


<br><br><br>

<h2>HOW TO USE FUNCTIONS</h2>
<p>
A number of functions are available for use in 
<a href="scripts.html">
 scripts
</a>
, for a wide range of purposes including processing of arithmetic, strings
dates, times, 
, and so on.  
Functions usually take one or more arguments and return a value.<tt> </tt>
Functions may be used with 
<a href="set.html">
 #set
</a>
,
<a href="call.html">
 #call
</a>
, or as operands in
<a href="if.html">
 #if/#elseif
</a>
<a href="condex.html">
 conditional expressions
</a>
 .  
<p>
Custom functions may be coded and added to the file <tt>custom.c</tt>,
and accessed like any of the built in functions, except that the
names of custom functions should begin with a
double dollar sign ($$) when invoked from scripts.<tt> </tt>

<br><br><br>

<h2>FUNCTION SYNTAX</h2>
Function names always start with a dollar sign (<b>$</b>).<tt> </tt>
Function arguments are enclosed by parentheses and if more than one
argument, separated by commas (,).  For example:
<dl>
<dt><dd><p>
<tt>$formatfloat( @NUM, "%7.2f" )</tt>
</dl>
<p>
Function calls may not be nested, ie. function arguments may not be functions.<tt> </tt>

<br><br><br>

<p>
In the following summaries, the function name appears along with a
template for arguments that must be supplied.<tt> </tt>

<br><br><br>
<a name=ploticus></a>
<h2>PLOTTING</h2>
Note: the functions in this section may be used with a double dollar sign ($$)
for faster function name search.<tt> </tt>
<p>
<b>$inrange( value, axis )</b>   or
<br>
<b>$inrange( value, axis, min, max )</b>
<dl>
<dt><dd><p>
Return 1 if <i>value</i> within a range on the given <i>axis</i>.<tt> </tt>
<i>min</i> and <i>max</i> are optional; if given they determine the range.<tt> </tt>
If they are not given the range is the range of the axis within the
plotting area.<tt> </tt>

</dl>
<p>
<b>$icolor( i )</b>
<dl>
<dt><dd><p>
Return one of 20 preselected colors.  The color sequence was
selected to give good contrast between nearby entries.<tt> </tt>
<i>i</i> allowable range is 1 to 20; values out of this range
are modulo into range.<tt> </tt>
<br>
Example: <tt>#set COLOR = $icolor( 2 )

</tt></dl>
<p>
<b>$fieldname( n )</b>
<dl>
<dt><dd><p>
Return the field name assigned to field <i>n</i>.  First is 1.<tt> </tt>
If no field name was defined, <tt>noname</tt> is returned.<tt> </tt>

</dl>
<p>
<b>$dataitem( row, field )
</b><dl>
<dt><dd><p>
Return the contents of the item in <i>row</i> and <i>field</i> of
the current data set.  <i>row</i> is a number, first is 1.<tt> </tt>
<i>field</i> is either a number or an assigned name.<tt> </tt>

</dl>
<p>
<b>$data_to_absolute( axis, val )</b>
<dl>
<dt><dd><p>
Given a data location <i>va</i> in either X or Y space (specified by
<i>axis</i>), return the absolute location.<tt> </tt>

</dl>
<p>
<b>$nextstub( maxlen )</b>
<dl>
<dt><dd><p>
Returns the text of a defined category or pltab row stub.<tt> </tt>
Usually called multiple times within a loop; the result is used to build an expression to
select data rows.  The first time it is called, the first category or row stub text will 
be returned; second time, the second category or row stub text will be returned, and so on.<tt> </tt>
The length will be limited to <i>maxlen</i>.  Any embedded spaces will be converted to underscores.<tt> </tt>
<dt><dd><p>
Example: <tt>#set S = $nextstub(5)</tt>
<dt><dd><p>
A gallery example where this is used is
<a href="../tabgallery/caselist.html">
 caselist
</a>

</dl>
<p>
<b>$sleep( n )</b>
<dl>
<dt><dd><p>
Delay for <i>n</i> seconds.  
Occasionally useful when viewing plots interactively.<tt> </tt>

</dl>
<p>
<b>$getclick()</b>
<dl>
<dt><dd><p>
Produce a "More.." button and wait for user to click on it.<tt> </tt>
Upon the click, return.<tt> </tt>
Occasionally useful when viewing plots interactively.<tt> </tt>


<a name=arithmetic></a>
<br><br><br>

</dl>
<h2>ARITHMETIC AND NUMBERS</h2>

<p>
<b>$arith(exp)</b> 
<dl>
<dt><dd><p>
Simplistic arithmetic expression evaluator. 
<i>exp</i> is an expression made up of numbers and the arithmetic operators
<tt>+ - * /</tt>.<tt> </tt>
No embedded spaces nor parentheses are allowed within the expression.<tt> </tt>
Evaluation is strictly left to right.<tt> </tt>
Unary plus/minus are allowed.<tt> </tt>
<br>
Example: <tt>#set RESULT = $arith(2+8/5)</tt>  (result: 2)
<br>
Example: <tt>#set RESULT = $arith(2+-8)</tt>  (result: -6)

</dl>
<p>
<b>$arithl(exp)</b>
<dl>
<dt><dd><p>
Same as <b>$arith()</b> except 
lazy, i.e. non-numeric operands 
are accepted and treated as if they were 0.  

</dl>
<p>
<b>$isnumber(s)</b>
<dl>
<dt><dd><p>
Returns 1 if <i>s</i> is a valid number, 0 if not.<tt> </tt>
<br>
Example: <tt>#set RESULT = $isnumber(-0.24)</tt>  (result: 1)
<br>
Example: <tt>#set RESULT = $isnumber(=)</tt>  (result: 0)

</dl>
<p>
<b>$formatfloat(x,fmt)</b>
<dl>
<dt><dd><p>
Format <i>x</i> using printf-style format string <i>fmt</i>.<tt> </tt>
May also be used to format integers by using a <i>fmt</i> such as <tt>%03.0f</tt>.<tt> </tt>
<br>
Example: <tt>#set RESULT = $formatfloat( 3.4425, "%3.2f" )</tt> (result: 3.44)

</dl>
<p>
<b>$inr(n,lo,hi)</b>
<dl>
<dt><dd><p>
See if <i>n</i> is within the numeric range of <i>lo</i>
to <i>hi</i>.  Returns 1 if so, 0 if not.  Non-numeric <i>n</i> always returns 0.<tt> </tt>

</dl>
<p>
<b>$numgroup( val, h, mode )</b>
<dl>
<dt><dd><p>
Convert <i>val</i> to a nearby multiple of <i>h</i>.<tt> </tt>
Useful in grouping a set of numbers into bins.<tt> </tt>
<i>mode</i> may be either <tt>low</tt>, <tt>mid</tt>, or <tt>high</tt>.   
For example, if f is 73 and h is 10, function returns 70, 75, or 80 for modes 
<tt>low</tt>, <tt>mid</tt>, <tt>high</tt> respectively.<tt> </tt>

</dl>
<p>
<b>$autoround(val,d)</b>
<dl>
<dt><dd><p>
Round <i>val</i> to a reasonable precision.<tt> </tt>
Use a value of 0 for <i>d</i> for normal behavior.  Increase <i>d</i> to
get more precision, reduce <i>d</i> to get less precision.<tt> </tt>
<br>
Example: <tt>#set X = $autoround( @X, 0 )</tt>

</dl>
<p>
<b>$math(what,val)</b>
<dl>
<dt><dd><p>
Mathematical functions on <i>val</i>.  
<pre>
what	returns
----    -------
abs	absolute value (integer or floating point)
</pre>
<br>
Example: <tt>#set X = $math(abs,@X)</tt>

</dl>
<p>
<b>$random()</b>
<dl>
<dt><dd><p>
Returns a random number between 0.0 and 1.0.<tt> </tt>

<a name=strings></a>
<br><br><br>

</dl>
<h2>STRINGS</h2>

<p>
<b>$len(s)</b>
<dl>
<dt><dd><p>
Return the length of <i>s</i>.<tt> </tt>

</dl>
<p>
<b>$change(s1,s2,string)</b>
<dl>
<dt><dd><p>
Change all occurances of <i>s1</i> to <i>s2</i> in string.<tt> </tt>
<br>
Example: <tt>#set T = $change( "&lt;", "&lt;sup&gt;", @T )</tt>

</dl>
<p>
<b>$expand( s )</b>
<dl>
<dt><dd><p>
Expand all @variables present in <i>s</i>.<tt> </tt>
Example: 
<pre>
 #set B = "@A world"
 #set A = hello
 #set C = $expand( @B )
</pre>
Variable C would then contain <tt>hello world</tt>.<tt> </tt>

</dl>
<p>
<b>$substring(s,n,len)</b>
<dl>
<dt><dd><p>
Return a substring of <i>s</i>.  Substring begins at character <i>n</i> (first is 1)
for a maximum length of <i>len</i>.<tt> </tt>
<br>
Example: <tt>$substring( "abcde", 3, 99 )</tt> would give <tt>cde</tt>


</dl>
<p>
<b>$changechars(clist,s,newchar)</b>
<dl>
<dt><dd><p>
If string <i>s</i> contains any of chars in <i>clist</i>, change that
character to <i>newchar</i>.  
<b>clist</b> may be passed as the word <tt>comma</tt> to represent a comma (,).<tt> </tt>
<br>
Example: <tt>#set RESULT = $changechars("*'", @S, "_" )</tt>

</dl>
<p>
<b>$deletechars(clist,s)</b>
<dl>
<dt><dd><p>
If string <i>s</i> contains any of chars in <i>clist</i>, delete that character.<tt> </tt>
<br>
Example: <tt>#set RESULT = $deletechars("*'",@S)</tt>

</dl>
<p>
<b>$contains(clist,s)</b>
<dl>
<dt><dd><p>
If string <i>s</i> contains any of chars in <i>clist</i>, return position
(first=1) of the first occurance.  Return 0 if none found.  
<i>clist</i> may be passed as the word <tt>comma</tt> to represent a comma (,).<tt> </tt>
<br>
Example: <tt>#set RESULT = $contains( "*'", @S )</tt>
<br>
Example: <tt>#set RESULT = $contains( ",", @S )</tt>

</dl>
<p>
<b>$fuzzymatch(s1,s2,degree)</b>
<dl>
<dt><dd><p>
Perform an approximate match of <i>s1</i> against <i>s2</i>.<tt> </tt>
A wildcard character '*' at the beginning or end of <i>s2</i> indicates
that a match can occur anywhere within <i>s1</i> (eg. smith* would match
smithington and *smith would match harrowsmith; *smith* would match
both).  If there are no asterisks, lengths of the two strings must be similar.<tt> </tt>
<br>
<i>degree</i> changes the 'looseness' of the match.<tt> </tt>
5 = strict, 4 = medium-strict, 3 = medium 2= loose, 1 = very loose.<tt> </tt>
<br>
Returns 1 on a match, 0 not.<tt> </tt>
<br>
Example: <tt>#set STAT = $fuzzymatch(hello,hillo,3)</tt> (result: <tt>1</tt>)
<br>
Example: <tt>#set STAT = $fuzzymatch(hello,hillo,5)</tt> (result: <tt>0</tt>)


</dl>
<p>
<b>$lowerc(string)</b>
<dl>
<dt><dd><p>
Return the lower-case equivalent of <i>string</i>.<tt> </tt>
<br>
Example: <tt>#set RESULT = $lowerc(HELLO)</tt> (result: <tt>hello</tt>)

</dl>
<p>
<b>$upperc(string)</b>
<dl>
<dt><dd><p>
Return the upper-case equivalent of <i>string</i>
<br>
Example: <tt>#set RESULT = $upperc(Hello)</tt> (result: <tt>HELLO</tt>)


</dl>
<p>
<b>$strcat(s,t)</b>
<dl>
<dt><dd><p>
Return the concatenatation of strings <i>s</i> and <i>t</i>
<br>
Example: <tt>#set RESULT = $strcat(ABC,XY)</tt>  (result: <tt>ABCXY</tt>)

</dl>
<p>
<b>$ntoken( n, s )</b>
<dl>
<dt><dd><p>
return the <i>n</i>th whitespace-delimited token in <i>s</i>.<tt> </tt>

</dl>
<p>
<b>$extractnum( s )</b>
<dl>
<dt><dd><p>
extract the first numeric entity embedded anywhere in <i>s</i> and return it.<tt> </tt>


<a name=commalists></a>
<br><br><br>

</dl>
<h2>COMMALISTS</h2>
These functions operate on a string which is in the form of a 
<a href="commalist.html">
 commalist
</a>
 .<tt> </tt>

<p>
<b>$count(str,list)</b>
<dl>
<dt><dd><p>
Count the number of times <i>str</i> appears in 
<i>list</i>.  If <i>str</i> is passed as <tt>*</tt> then this function
will count the number of members in the list.<tt> </tt>
<br>
Example: <tt>#set RESULT = $count( "hello,aba,gabba,jabba" )</tt> (result: 0)
<br>
Example: <tt>#set RESULT = $count( "x", "x,y,x,y,y,z,x" )</tt> (result: 3)

</dl>
<p>
<b>$addmember(newmem,list)</b>
<dl>
<dt><dd><p>
Append a new member <i>newmem</i> to end of <i>list</i>.<tt> </tt>
If <i>list</i> is empty before call, result will have one member.<tt> </tt>
<br>
Example: <tt>#set RESULT = $addmember( "red", @MYLIST )</tt>

</dl>
<p>
<b>$nmember(n,list)</b>
<dl>
<dt><dd><p>
Get the <i>n</i>th member of <i>list</i>.  
<br>
Example: <tt>#set RESULT = $nmember( 2, "a,b,c,d,e" )</tt> (result: <tt>b</tt><b>)

</b></dl>
<p>
<b>$commonmembers( list1, list2, mode )
</b><dl>
<dt><dd><p>
Detect if <i>list1</i> and <i>list2</i> have any members in common.<tt> </tt>
Returns 0 if no members in common.<tt> </tt>
If <i>mode</i> is <tt>"count"</tt>, then the number in common is returned
(for a,b,c vs. c,d,e this would be 1; for a,a,a vs a,b,c it would be 3).<tt> </tt>
Otherwise, when a match is found 1 is returned immediately.<tt> </tt>
<br>
Example: <tt>#set MATCH = $commonmembers( "a,b,c,d,e", "c,d,ee", "count" )</tt>  (result: <tt>2</tt>)

</dl>
<p>
<b>$homogenous( list )</b>
<dl>
<dt><dd><p>
Return 1 if all members of list are the same, 0 if there are any differences
among members.<tt> </tt>
If <i>list</i> has only 1 member, 1 is returned.  
If <i>list</i> is empty, 0 is returned.<tt> </tt>

</dl>
<p>
<b>$makelist( s )</b>
<dl>
<dt><dd><p>
Convert <i>s</i>, a list of items separated by commas and/or whitespace, 
and return a commalist.<tt> </tt>
Useful for building commalists from user input.<tt> </tt>
<br>
Example: <tt>#set LIST = $makelist( "1101   1102 1103" )</tt>  (result: <tt>1101,1102,1103</tt>)
<br>
Example: <tt>#set LIST = $makelist( "1101,  1102, 1103" )</tt>  (result: <tt>1101,1102,1103</tt>)

<a name=shell></a>
<br><br><br>

</dl>
<h2>SHELL COMMAND INTERFACE</h2>
Functions related to the shell interface are described on the
<a href="shell.html">
 #shell manual page
</a>
 .<tt> </tt>


<a name=sql></a>
<br><br><br>

<h2>SQL DATABASE INTERFACE</h2>
Functions related to SQL interface are described on the
<a href="sql.html">
 #sql manual page
</a>
 .<tt> </tt>


<a name=dates></a>
<br><br><br>

<h2>DATES</h2>
<p>
These functions work with 
<a href="dates.html">
 dates in various notations
</a>
 .  Some date-related parameters may be set in the 
<a href="config.html">
 project config file
</a>
<p>
The default date format is <tt>mmddyy</tt>.<tt> </tt>
Unless otherwise specified, these functions expect date arguments
to be in the "current date format".<tt> </tt>

<p>
<b>$setdatefmt(format)</b>
<dl>
<dt><dd><p>
Set the current date format.<tt> </tt>
<br>
Example: <tt>#call $setdatefmt( "yyyymmdd" )</tt>

</dl>
<p>
<b>$formatdate(date,newformat)</b>
<dl>
<dt><dd><p>
Return <i>date</i>, formatted to <i>newformat</i>.<tt> </tt>
Use to convert dates to different notations, to extract year, month, day
components, or to get weekday equivalent.<tt> </tt>
Available formats are described 
<a href="dates.html">
 here
</a>
<br>
Example: <tt>#set RESULT = $formatdate( @D, "yyyymmmdd" )</tt>

</dl>
<p>
<b>$datevalid(date)</b>
<dl>
<dt><dd><p>
Return 1 if <i>date</i> is a valid one in the current date format;
return 0 if it is not.<tt> </tt>
<br>
Example: <tt>#if $datevalid(@apptdate) != 1</tt>

</dl>
<p>
<b>$todaysdate()</b>
<dl>
<dt><dd><p>
Return the current date.  It will be in the date format currently in effect.<tt> </tt>
<br>
Example: <tt>#set RESULT = $todaysdate()</tt>

</dl>
<p>
<b>$daysdiff(date1,date2)</b>
<dl>
<dt><dd><p>
Return the difference in days between <i>date1</i> and <i>date2</i>.<tt> </tt>
<br>
Example: <tt>#set RESULT = $daysdiff( 011298, 010198 )</tt> (result: 11)

</dl>
<p>
<b>$julian(date)</b>
<dl>
<dt><dd><p>
Return the julian (number of days since Jan 1, 1977) equivalent of <i>date</i>.<tt> </tt>
<i>date</i> should be a date in current format, or the special symbol <tt>today</tt>.<tt> </tt>

</dl>
<p>
<b>$jultodate(jul)</b>
<dl>
<dt><dd><p>
Return the date (in current format) that is equivalent to julian value <i>jul</i>.<tt> </tt>

</dl>
<p>
<b>$dateadd(date,ndays)</b>
<dl>
<dt><dd><p>
Return the date resulting when <i>ndays</i> are added to <i>date</i>.  
<br>
Example: <tt>#set RESULT = $dateadd( 010198, 11 )</tt> (result: 011298)

</dl>
<p>
<b>$dategroup( interval, mode, input )</b>
<dl>
<dt><dd><p>
Take date, datetime, or time <i>input</i> value, and adjust it for 
grouping purposes.  For example, after a set of dates
are processed using <tt>$dategroup( week, mid, .. )</tt>, the result can be tabulated to
get a weekly distribution.  
Allowable <i>interval</i> values are <tt>week  month  quarter  year  day  hour</tt>.<tt> </tt>
Allowable <i>mode</i> values are <tt>mid</tt> and <tt>first</tt>.<tt> </tt>
First character is sufficient for these two args.<tt> </tt>

</dl>
<p>
<b>$yearsold(birthdate,testdate)</b>
<dl>
<dt><dd><p>
Return the integer age in years as of 
<i>testdate</i> of a person born on <i>birthdate</i>.<tt> </tt>
<br>
Example: <tt>#set RESULT = $yearsold( 062661, 022098 )</tt> (result: 36)

</dl>
<p>
<b>$setdateparms(parmname,value)</b>
<dl>
<dt><dd><p>
Set a date parameter.  See 
<a href="config.html">
 config file documentation
</a>
for descriptions of these parameters, including
strictness of date format checking, 
the century pivot year, and lazy dates.<tt> </tt>
<br>
A pivot year is used to accomodate two-digit year values.<tt> </tt>
<br>
A lazy date has 00 as the day and/or month portion and is usually
used in situations where the day and/or month is unknown or unavailable.<tt> </tt>
<br>
Strictness of date format checking: by default the length of a presented date must be
consistent with the format specification.  For example, an mm/dd/yy date must be
8 or 10 characters long; other lengths result in an error.<tt> </tt>
This strictness may be relaxed by doing: <tt>#set STATUS = $setdateparms(Strictdatelengths,no)</tt>
<br>
Example of setting the pivot year: <tt>#set STATUS = $setdateparms(Pivotyear,90)</tt>
<br>
Example of allowing lazy days: <tt>#set STATUS = $setdateparms(Lazydates,days)</tt>
<br>
Example of allowing lazy days and months: <tt>#set STATUS = $setdateparms(Lazydates,both)</tt>

<a name=times></a>
<br><br><br>

</dl>
<h2>TIMES</h2>
These functions work with 
<a href="times.html">
 time values
</a>
in various notations.<tt> </tt>

<p>
<b>$settimefmt(fmt)</b>
<dl>
<dt><dd><p>
Set the current time notation to <i>fmt</i>.<tt> </tt>
Available notations are <tt>HH:MM:SS</tt>, <tt>HH:MM</tt>, and <tt>MM:SS</tt>.<tt> </tt>
(A leading HH can handle single digit hour values; a leading MM
can handle single digit minute values).<tt> </tt>
<br>
Example: <tt>#set RESULT = $settimefmt(MM:SS)</tt>
These functions work with time values.<tt> </tt>

</dl>
<p>
<b>$time()</b>
<dl>
<dt><dd><p>
Return the current time in <tt>hh:mm:ss</tt> format.<tt> </tt>
<br>
Example: <tt>#set RESULT = $time()</tt>

</dl>
<p>
<b>$timevalid(time)</b>
<dl>
<dt><dd><p>
Return 1 if <i>time</i> is valid in the current time format;
return 0 if it is not.<tt> </tt>
<br>
Example: <tt>#if $timevalid(@appttime) != 1</tt>

</dl>
<p>
<b>$formattime(time,newformat)</b>
<dl>
<dt><dd><p>
Take <i>time</i>, which is in the current time format,
and reformat it using <i>newformat</i>.<tt> </tt>
<br>
Example: <tt>#set t2 = $formattime( "14:22", "hh:mma" )

</tt></dl>
<p>
<b>$timesec()</b>
<dl>
<dt><dd><p>
Get number of seconds since midnight for the current time.<tt> </tt>
<br>
Example: <tt>#set RESULT = $timesec()</tt>

</dl>
<p>
<b>$tomin(t)</b>
<dl>
<dt><dd><p>
Take <i>t</i> (a value in the current time notation) and return the equivalent,
expressed in # of minutes since 0:00:00.  Result is float,
with any seconds expressed as the decimal portion of a minute. 
<br>
Example: <tt>#set RESULT = $tomin( "3:45" )</tt>
 
</dl>
<p>
<b>$frommin(m)</b>
<dl>
<dt><dd><p>
Inverse of $tomin(), where <i>m</i> is a float minutes value.<tt> </tt>
Result is equivalent time in current notation.<tt> </tt>
<br>
Example: <tt>#set RESULT = $frommin( 3.75 )</tt>

</dl>
<p>
<b>$timediff(t1,t2)</b>
<dl>
<dt><dd><p>
Find the difference between two times 
<i>t1</i> and <i>t2</i> (both in current notation).  Result is expressed 
in float minutes (any seconds expressed as fraction of a minute) 
<br>
Example: <tt>#set RESULT = $timediff( "3:43", "2:28" )</tt>

<a name=checksums></a>
<br><br><br>

</dl>
<h2>CHECKSUMS</h2>
Checksum routines use an odd-even algorithm that takes an integer and
computes a checksum digit 0 - 9 or x.  This checksum digit may be
used to guard against key errors and transposed digits.<tt> </tt>
<p>

<b>$checksumvalid(s)</b>
<dl>
<dt><dd><p>
Returns 1 if <i>s</i> is a valid
number with checksum.  0 if not.<tt> </tt>
<br>
Example: <tt>#if $checksumgood(39) = 1</tt> (result: true)

</dl>
<p>
<b>$checksumencode(i)</b>
<dl>
<dt><dd><p>
Result is integer <b>i</b> with 
a checksum digit appended.<tt> </tt>
<br>
Example: <tt>#set CHECKNUM = $checksumencode(29)</tt> (result: 294)

</dl>
<p>
<b>$checksumnext(s)</b>
<dl>
<dt><dd><p>
Take <i>s</i> which is a number 
including trailing checksum digit, and increment the number and 
recompute new checksum digit.  Result is returned.<tt> </tt>
Example: <tt>#set RESULT = $checksumnext(39) = 1</tt> (result: 41)


<a name=misc></a>
<br><br><br>

</dl>
<h2>MISCELLANEOUS</h2>
<p>
<b>$getenv(varname)</b>
<dl>
<dt><dd><p>
Return the contents of environment variable <i>varname</i>.<tt> </tt>


</dl>
<p>
<b>$uniquename()</b>
<dl>
<dt><dd><p>
Return a short identifier generated
using the current date, time to the current second, and process id.  
The name will be unique on a per-host basis.<tt> </tt>

</dl>
<p>
<b>$tmpfilename(tag)</b>
<dl>
<dt><dd><p>
Generate a unique (on a per-host basis) temporary file name, suitable
for use in shell commands.  Uses <b>tmpdir</b> as specified in
<a href="config.html">
 project config file
</a>
 .  Format of the name is <i>tmpdir</i><tt>/</tt><i>tag</i><tt>.</tt><i>uniquename</i> where
<i>uniquename</i> is a short name generated using the current date, current time
to the second, and process id.  <i>tag</i> may be passed as a zero length string
if desired.<tt> </tt>

</dl>
<p>
<b>$fileexists( dir, name )</b>
<dl>
<dt><dd><p>
Return 1 if the requested file can be opened, 0 otherwise.<tt> </tt>
<i>dir</i> indicates the directory that <i>name</i> is relative to
and may be one of <tt>/</tt>, <tt>scriptdir</tt>, <tt>datadir</tt>, <tt>tmpdir</tt>.<tt> </tt>
<br>
Example: <tt>#set A = $fileexists( tmpdir, "mytmp" )</tt>

</dl>
<p>
<b>$ref( varname ) </b>
<dl>
<dt><dd><p>
Return the contents of <i>varname</i>.  May be useful when a variable contains
the name of another variable, to extract the value of the other variable.<tt> </tt>
Example:
<br>
<pre>
  #set A = "hello"
  #set B = "A"
  #set C = $ref(@B)
</pre>
<br>
C would then contain <tt>hello</tt>.<tt> </tt>

</dl>
<p>
<b>$def( varname ) </b>
<dl>
<dt><dd><p>
Return 1 if varname has been set to a value.<tt> </tt>
Return 0 otherwise.<tt> </tt>



<br>
<br>
</td></tr>
<td align=right>
<a href="Welcome.html">
<img src="../doc/ploticus.gif" border=0></a><br><small>data display engine &nbsp; <br>
<a href="../doc/Copyright.html">Copyright Steve Grubb</a>
<br>
<br>
<center>
<img src="../gallery/all.gif">
</center>
</td></tr>
</table>
</dl>
<p><hr>
Markup created by <em>unroff</em> 1.0,&#160;<tt> </tt>&#160;<tt> </tt>December 14, 2001.
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