Search
Ploticus >
Scripts >
Categories of available functions:
plotting
arithmetic
strings
commalists
shell
sql
dates
times
misc
HOW TO USE FUNCTIONS
A number of functions are available for use in
ploticus scripts
and
proc getdata filters
, for a wide range of purposes including processing of arithmetic, strings
dates, times,
commalists
, and so on.
Functions usually take one or more arguments and return a value.
Functions may be used with
#set
,
#call
or as operands in
#if/#elseif
conditional expressions
.
Custom functions may be coded and added to the file custom.c,
and accessed like any of the built in functions, except that the
names of custom functions should begin with a
double dollar sign ($$) when invoked from scripts.
FUNCTION SYNTAX
Function names always start with a dollar sign ($).
Function arguments are enclosed by parentheses and if more than one
argument, separated by commas (,). For example:
$formatfloat( @NUM, "%7.2f" )
Function calls may not be nested, ie. function arguments may not be functions.
In the following summaries, the function name appears along with a
template for arguments that must be supplied.
PLOTTING
Note: the functions in this section may be used with a double dollar sign ($$)
for faster function name search.
Because of the way ploticus script files are parsed,
#endproc should be used to terminate any #proc previous to these function calls,
so that the proc executes before the function call.
$inrange( value, axis ) or
$inrange( value, axis, min, max )
Return 1 if value within a range on the given axis.
min and max are optional; if given they determine the range.
If they are not given the range is the range of the axis within the
plotting area.
$icolor( i )
Return one of 20 preselected colors. The color sequence was
selected to give good contrast between nearby entries.
i allowable range is 1 to 20; values out of this range
are modulo into range.
Example: #set COLOR = $icolor( 2 )
$fieldname( n )
Return the field name assigned to field n. First is 1.
If no field name was defined, noname is returned.
$dataitem( row, field )
Return the contents of the item in row and field of
the current data set. row is a number, first is 1.
field is either a number or an assigned name.
$defaultinc( min, max )
Return a reasonable increment given numeric min and max,
using the same algorithm used with axis stub increments.
Example: #set inc = $defaultinc( 0, 200 )
$changeunits( axis, newunitspec )
Change the scaling units associated with an existing axis.
Example: #call $changeunits( x, "date nqyy" )
$squelch_display( mode )
#call $squelch_display( 1 ) .. will squelch all drawing activity.
#call $squelch_display( 0 ) .. will resume drawing activity.
Note that #endproc must terminate any #proc previous to these function calls. (version 2.30+)
$boundingbox( mode )
#call $boundingbox( 0 ) .. subsequent drawing does not influence the bounding box and hence the crop
#call $boundingbox( 1 ) .. restore to normal mode of operation.
Note that #endproc must terminate any #proc previous to these function calls. (version 2.30+)
$data_to_absolute( axis, val )
Given a data location va in either X or Y space (specified by
axis), return the absolute location.
$sleep( n )
Delay for n seconds.
Occasionally useful when viewing plots interactively.
$getclick()
Produce a "More.." button and wait for user to click on it.
Upon the click, return.
Occasionally useful when viewing plots interactively.
$errmsgpre( tag )
Allows developer to set the first portion of all ploticus error messages to tag
(it will stay in effect until explicitly set again).
For example, where a web page generates multiple plots it may be useful in identifying
which plot had the error.
$textwidth( text, font, size)
Return horizontal width of freetype bounding box.
Useful only with freetype fonts, otherwise it returns 0. Suggested/contributed by Erik Zachte.
$rewritenums( f )
takes a numeric quantity f and
returns it rewritten for display purposes, applying
numbernotation (as specified in your proc settings or config file).
ARITHMETIC AND NUMBERS
$arith( exp, format )
Simplistic arithmetic expression evaluator.
exp is an expression made up of numbers and the arithmetic operators
+  * /.
No embedded spaces nor parentheses are allowed within the expression.
Evaluation is strictly left to right.
Unary plus/minus are allowed.
In versions 2.30+ scientific notation eg. 3.74e07 is supported.
format is an optional printf(3) display format specifier controlling
the format of the result,
eg. %.0f. Default format is %g, which should suffice for all but very
large or very small values. For more on format specifiers see your manual page on printf(3).
Example: #set RESULT = $arith(2+8/5) (result: 2)
Example: #set RESULT = $arith(2+8) (result: 6)
Example: #set RESULT = $arith( 18*1000000000 , "%.f" )
Example: #set RESULT = $arith( 18*.0000001 , "%.9f" )
$arithl(exp)
Same as $arith() except
lazy, i.e. nonnumeric operands
are accepted and treated as if they were 0.
$isnumber(s)
Returns 1 if s is a valid number, 0 if not.
In versions 2.30+ scientific notation is supported.
Example: #set RESULT = $isnumber(0.24) (result: 1)
Example: #set RESULT = $isnumber(=) (result: 0)
$formatfloat(x,fmt)
Format x using printfstyle format string fmt.
May also be used to format integers by using a fmt such as %03.0f.
Example: #set RESULT = $formatfloat( 3.4425, "%3.2f" ) (result: 3.44)
$inr(n,lo,hi)
See if n is within the numeric range of lo
to hi. Returns 1 if so, 0 if not. Nonnumeric n always returns 0.
$numgroup( val, h, mode )
Convert val to a nearby multiple of h.
Useful in grouping a set of numbers into bins.
mode may be either low, mid, or high.
For example, if f is 73 and h is 10, function returns 70, 75, or 80 for modes
low, mid, high respectively.
$autoround(val,d)
Round val to a reasonable precision.
Use a value of 0 for d for normal behavior. Increase d to
get more precision, reduce d to get less precision.
Example: #set X = $autoround( @X, 0 )
$math(what,a,b)
Various mathematical functions. a and b can be integer or floating point
unless otherwise noted below.
what returns
 
abs absolute value of a
mod a modulo b
div integer division a / b (a and b must be integers)
pow a raised to b
mag a multiplied by 10 to the b
log+1 the natural log of a, plus 1.0
exp1 the exponential of a, minus 1.0
sqrt the square root of a
Example: #set X = $math(abs,57) would return 57.
Example: #set X = $math(mod,10,6) would return 4.
$random()
Returns a random number between 0.0 and 1.0.
$ranger( rangespec )
Convert an integer range specification to an enumerated list of all integers covered.
Range specifications can contain integers separated by commas or dashes, with no embedded spaces.
Example:
#set RANGE = "5,8,1115"
#set LIST = $ranger( @RANGE )
LIST would then contain 5,8,11,12,13,14,15
STRINGS
$len(s)
$change(s1,s2,string)
Change all occurances of s1 to s2 in string.
Example: #set T = $change( "<", "<sup>", @T )
$expand( s )
Expand all @variables present in s.
Example:
#set B = "@A world"
#set A = hello
#set C = $expand( @B )
Variable C would then contain hello world.
$substring(s,n,len)
Return a substring of s. Substring begins at character n (first is 1)
for a maximum length of len.
This function may also be used to count back from the end of the string and take
a substring to do this, specify a negative n (see 2nd example below).
Example: $substring( "abcde", 3, 99 ) would give cde
Example: $substring( "abcde", 2, 99 ) would give de
$changechars( clist, teststring, newchar )
The result will be
teststring, with each instance of any char in clist changed to newchar.
clist is either a single character or it may be one of these special symbols: not_alnum (change all nonalphanumeric chars);
not_print (change all chars decimal ascii < 32 or > 127)l whitespace (change all whitespace chars).
Example: #set RESULT = $changechars("*'", @S, "_" )
$deletechars( clist, teststring )
The result will be
teststring, with each instance of any char in clist deleted.
clist may be a string of one or more characters, or one of these special symbols: not_alnum (delete all nonalphanumeric chars);
not_print (delete all chars decimal ascii < 32 or > 127)l whitespace (delete all whitespace chars).
Example: #set RESULT = $deletechars("*'",@S)
$stripws( s, mode )
Remove whitespace characters from s.
If mode is "any", all whitespace characters are removed.
Otherwise only leading and trailing whitespace is stripped off.
$contains(clist,s)
If string s contains any of chars in clist, return position
(first=1) of the first occurance. Return 0 if none found.
clist may be passed as the word comma to represent a comma (,).
Example: #set RESULT = $contains( "*'", @S )
Example: #set RESULT = $contains( ",", @S )
$lowerc(string)
Return the lowercase equivalent of string.
Example: #set RESULT = $lowerc(HELLO) (result: hello)
$upperc(string)
Return the uppercase equivalent of string
Example: #set RESULT = $upperc(Hello) (result: HELLO)
$capit(string)
Return the string with first letter capitalized. (added 5/15/08).
Example: #set RESULT = $upperc(hello) (result: Hello)
$strcmp(s,t)
Return an integer representation of the difference in magnitude of s and t,
using ascii order.
Note: don't use this for #if statement equality comparisons; simple = and != should
be used instead.
Example: #set RESULT = $strcmp(ABC,XY) (result will be a negative integer)
Example: #set RESULT = $strcmp(XY,ABC) (result will be a positive integer)
$strcat(s,t)
Return the concatenatation of strings s and t
Example: #set RESULT = $strcat(ABC,XY) (result: ABCXY)
$ntoken( n, s [,c] )
Return the nth whitespacedelimited token in s.
Or if c is specified as a single character, it is used as the delimiter... return the nth field in s (added 3/28/08).
$counttokens( s [,c] )
Return the number of whitespacedelimited tokens in s.
Or if c is specified as a single character, it is used as the delimiter... return the nth field in s (added 5/15/08).
$extractnum( s )
Extract the first numeric entity embedded anywhere in s and return it.
$wildcmp( s1, s2 )
Return the result of a wildcardenabled match s1 vs. s2. s2 can contain wild cards.
Return value is 0 on a match, 1 if s1 is "less than" s2, and 1 if s1 is "greater than" s2.
$encrypt( s, salt )
Returns the result of oneway encryption of s. Uses crypt(3C).
salt is optional 2 character perturbation string.
$urlencode( s )
Returns the urlencoded version of s.
$urldecode( s )
Returns the urldecoded version of s.
COMMALISTS
These functions operate on a string which is in the form of a
commalist
.
$count(str,list)
Count the number of times str appears in
list. If str is passed as * then this function
will count the number of members in the list.
Example: #if $count( "*", "a,b,c" ) = 3 (true)
Example: #set RESULT = $count( "hello", "aba,gabba,jabba" ) (result: 0)
Example: #set RESULT = $count( "x", "x,y,x,y,y,z,x" ) (result: 3)
$addmember(newmem,list)
Append a new member newmem to end of list.
If list is empty before call, result will have one member.
Example: #set RESULT = $addmember( "red", @MYLIST )
$deletemember(mem,list)
Remove a member mem from list.
Example: #set RESULT = $deletemember( "red", @MYLIST )
$nmember(n,list)
Get the nth member of list.
Example: #set RESULT = $nmember( 2, "a,b,c,d,e" ) (result: b)
$commonmembers( list1, list2, mode )
Detect if list1 and list2 have any members in common.
Returns 0 if no members in common.
If mode is "count", 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).
Otherwise, when a match is found 1 is returned immediately.
Example: #set MATCH = $commonmembers( "a,b,c,d,e", "c,d,ee", "count" ) (result: 2)
$homogenous( list )
Return 1 if all members of list are the same, 0 if there are any differences
among members.
If list has only 1 member, 1 is returned.
If list is empty, 0 is returned.
$makelist( s )
Convert s, a list of items separated by commas and/or whitespace,
and return a commalist.
Useful for building commalists from user input.
Example: #set LIST = $makelist( "1101 1102 1103" ) (result: 1101,1102,1103)
Example: #set LIST = $makelist( "1101, 1102, 1103" ) (result: 1101,1102,1103)
SHELL COMMAND INTERFACE
Functions related to the shell interface are described on the
#shell manual page
.
SQL DATABASE INTERFACE
Functions related to SQL interface are described on the
#sql manual page
.
DATES
These functions work with
dates in various notations.
The default date format is mmddyy.
Unless otherwise specified, these functions expect date arguments
to be in the "current date format".
$setdatefmt(format)
Set the current date format.
Example: #call $setdatefmt( "yyyymmdd" )
$formatdate(date,newformat)
Return date, formatted to newformat.
Use to convert dates to different notations, to extract year, month, day
components, or to get weekday equivalent.
Available formats are described
here
Example: #set RESULT = $formatdate( @D, "yyyymmmdd" )
$datevalid(date)
Return 1 if date is a valid one in the current date format;
return 0 if it is not.
Example: #if $datevalid(@apptdate) != 1
$todaysdate()
Return the current date. It will be in the date format currently in effect.
Example: #set RESULT = $todaysdate()
$daysdiff(date1,date2)
Return the difference in days between date1 and date2.
Example: #set RESULT = $daysdiff( 011298, 010198 ) (result: 11)
$julian(date)
Return the julian (number of days since Jan 1, 1970) equivalent of date.
date should be a date in current format, or the special symbol today.
$jultodate(jul)
Return the date (in current format) that is equivalent to julian value jul.
$dateadd(date,ndays)
Return the date resulting when ndays are added to date.
Example: #set RESULT = $dateadd( 010198, 11 ) (result: 011298)
$dategroup( interval, mode, input )
Take date, datetime, or time input value, and adjust it for
grouping purposes. For example, after a set of dates
are processed using $dategroup( week, mid, .. ), the result can be tabulated to
get a weekly distribution.
Allowable interval values are week month quarter year day hour.
Allowable mode values are mid and first.
First character is sufficient for these two args.
$yearsold(birthdate,testdate)
Return the integer age in years as of
testdate of a person born on birthdate.
Example: #set RESULT = $yearsold( 062661, 022098 ) (result: 36)
$setdateparms(parmname,value)
Set a date parameter.
You can set the
pivotyear, strictdatelengths, or lazydates attributes.
See the
config file documentation
for descriptions of these parameters.
Example of setting the pivot year: #set STATUS = $setdateparms(Pivotyear,90)
Example of allowing lazy days: #set STATUS = $setdateparms(Lazydates,days)
Example of allowing lazy days and months: #set STATUS = $setdateparms(Lazydates,both)
TIMES
These functions work with
time values
in various notations.
$settimefmt(fmt)
Set the current time notation to fmt.
Available notations are HH:MM:SS, HH:MM, and MM:SS.
(A leading HH can handle single digit hour values; a leading MM
can handle single digit minute values).
Example: #set RESULT = $settimefmt(MM:SS)
These functions work with time values.
$time()
Return the current time in hh:mm:ss format.
Example: #set RESULT = $time()
$timevalid(time)
Return 1 if time is valid in the current time format;
return 0 if it is not.
Example: #if $timevalid(@appttime) != 1
$formattime(time,newformat)
Take time, which is in the current time format,
and reformat it using newformat.
Example: #set t2 = $formattime( "14:22", "hh:mma" )
$timesec()
Get number of seconds since midnight for the current time.
Example: #set RESULT = $timesec()
$tomin(t)
Take t (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.
Example: #set RESULT = $tomin( "3:45" )
$frommin(m)
Inverse of $tomin(), where m is a float minutes value.
Result is equivalent time in current notation.
Example: #set RESULT = $frommin( 3.75 )
$timediff(t1,t2)
Find the difference between two times
t1 and t2 (both in current notation). Result is expressed
in float minutes (any seconds expressed as fraction of a minute)
Example: #set RESULT = $timediff( "3:43", "2:28" )
CHECKSUMS
Checksum routines use an oddeven 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.
$checksumvalid(s)
Returns 1 if s is a valid
number with checksum. 0 if not.
Example: #if $checksumgood(39) = 1 (result: true)
$checksumencode(i)
Result is integer i with
a checksum digit appended.
Example: #set CHECKNUM = $checksumencode(29) (result: 294)
$checksumnext(s)
Take s which is a number
including trailing checksum digit, and increment the number and
recompute new checksum digit. Result is returned.
Example: #set RESULT = $checksumnext(39) = 1 (result: 41)
MISCELLANEOUS
$getenv(varname)
Return the contents of environment variable varname.
$whoami()
Return a string containing euid,egid, where euid is the
current effective user id, and egid is the current effective group id.
$errormode( mode )
Control the display of error messages. Allowable values for mode are
stderr and stdout. For command line applications the default is
generally stderr; for CGI applications it is stdout, so that messages
are visible. To hide error messages in CGI applications, set mode to stderr.
$uniquename()
Return a short identifier generated
using the current date, time to the current second, and process id.
The name will be unique on a perhost basis.
$tmpfilename(tag)
Generate a unique (on a perhost basis) temporary file name, suitable
for use in shell commands. Uses tmpdir as specified in
project config file
. Format of the name is tmpdir/tag.uniquename where
uniquename is a short name generated using the current date, current time
to the second, and process id. tag may be passed as a zero length string
if desired.
$fileexists( dir, name )
Return 1 if the requested file can be opened, 0 otherwise.
dir indicates the directory that name is relative to
and may be one of /, scriptdir, tmpdir.
dir may also be datadir if using shSQL.
Example: #set A = $fileexists( tmpdir, "mytmp" )
$rename( pathname, newpathname )
$unlink( pathname )
$chmod( pathname, mode )
Do a chmod on pathname, setting it's file permissions to mode.
Allowable modes are: 644, 664, 666, 444, 640, and 660.
$chdir( dirpath )
$mkdir( newdirpath )
Initially sets the mode to 755; do a subsequent $chmod() for other protection modes.
$cleanname( name )
Strip out any punctuation and control characters
from name, leaving only letters, digits, and underscores.
Example: #set name = $cleanname( @name )
$ref( varname )
Return the contents of varname. May be useful when a variable contains
the name of another variable, to extract the value of the other variable.
Example:
#set A = "hello"
#set B = "A"
#set C = $ref(@B)
C would then contain hello.
$def( varname )
Return 1 if varname has been set to a value (even if the value is "").
Return 0 otherwise.
$isleep( n )
$showvars(mode)
For debug purposes.
Writes a list of every existing internal variable name to standard output, along with a count.
If mode is given as "values" variable contents are also written.
$fflush()
Flush standard output buffer. With quisp this can be used to immediately display
all content available so far.
