Difference between revisions of "Functions"
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==format== | ==format== | ||
| + | [[File:Format.pdf|page=1|thumb|256px|A very nice article written by Professor Don Colton, at the Brigham Young University of Hawaii]] | ||
:Syntax | :Syntax | ||
::<code>''string'' format(''string'' formatString[, ''dynamic'' value1[, .., ''dynamic'' valueN]])</code> | ::<code>''string'' format(''string'' formatString[, ''dynamic'' value1[, .., ''dynamic'' valueN]])</code> | ||
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::<code>format('The temperature outside is %.2f degrees Fahrenheit', [Temp sensor:temperature])</code> outputs <code>The temperature outside is 71.26 degrees Fahrenheit</code> | ::<code>format('The temperature outside is %.2f degrees Fahrenheit', [Temp sensor:temperature])</code> outputs <code>The temperature outside is 71.26 degrees Fahrenheit</code> | ||
::The <code>%.2f</code> translates to "format as <code>f</code>loat and use <code>.2</code> decimal places. | ::The <code>%.2f</code> translates to "format as <code>f</code>loat and use <code>.2</code> decimal places. | ||
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| − | |||
| − | |||
==indexOf== | ==indexOf== | ||
Revision as of 12:57, 23 May 2017
Functions are extensions to expressions that allow data processing and conversion. Here is a list of all defined functions
String functions
concat
- Syntax
string concat(dynamic value1, dynamic value2[, .., dynamic valueN])
- Returns
- Returns a string that is the concatenation of all the supplied values. This function accepts two or more input values.
contains
- Syntax
boolean contains(string haystack, string needle)
- Returns
- Returns true if the
needleis found anywhere in thehaystack
- Returns true if the
endsWith
- Syntax
boolean endsWith(string haystack, string needle)
- Returns
- Returns true if
haystackends with theneedle
- Returns true if
format
- Syntax
string format(string formatString[, dynamic value1[, .., dynamic valueN]])
- Returns
- Returns a string that is built based on the
formatStringwith arguments replaced by their corresponding values. Follows the java syntax forprintf(). See a quick reference here, or a more detailed reference Reference here. - Each % in the format string represents an argument and corresponds to a value (in order of appearance) in the value list. Each argument can have formatting settings, according to the reference provided.
- Returns a string that is built based on the
- Example
format('The temperature outside is %.2f degrees Fahrenheit', [Temp sensor:temperature])outputsThe temperature outside is 71.26 degrees Fahrenheit- The
%.2ftranslates to "format asfloat and use.2decimal places.
indexOf
- Syntax
integer indexOf(string haystack, string needle)
- Returns
- Returns the character index of the first occurrence of
needleinsidehaystack
- Returns the character index of the first occurrence of
- Examples
indexOf("hello world", 'l')outputs2
lastIndexOf
- Syntax
integer lastIndexOf(string haystack, string needle)
- Returns
- Returns the character index of the last occurrence of
needleinsidehaystack
- Returns the character index of the last occurrence of
- Examples
lastIndexOf("hello world", 'l')outputs9
left
- Syntax
string left(string value, integer length)
- Returns
- Returns the first
lengthcharacters invalue
- Returns the first
- Examples
left("hello world", 2)outputshe
lower
- Syntax
string lower(string value)
- Returns
- Returns the
valuebut with all lower case letters.
- Returns the
- Examples
lower("Hello World")outputshello world
mid
- Syntax
string mid(string value, integer start[, integer count = remaining])
- Arguments
start- provides the 0-based index of the first character to copy. Ifstartis negative, the counting starts from the end ofvalue.count- provides the number of characters to copy fromvalue. If not provided, all of the remaining characters fromvalueare returned, starting with character numberstart. Ifcountis negative, prior characters are returned.
- Returns
- Returns a substring of
value,countcharacters long, starting at character numberstart. Note that the first character in any string has index 0.
- Returns a substring of
- Examples
mid("Hello World", 2, 3)outputsllomid("Hello World", 2)outputsllo Worldmid("Hello World", -5, 2)outputsWomid("Hello World", -1, -3)outputsorl
random
- Syntax
dynamic random([integer range | dynamic value1, dynamic value2[, .., dynamic valueN]])
- Arguments
range- an integer number representing a rangevalue1..valueN- any kind of arguments, one will be randomly returned
- Returns
- Returns a random decimal number between
0and1if no arguments are provided, or a number between0andrange(inclusive) if a single argument is provided, or a randomly selected argument if two or more arguments are provided.
- Returns a random decimal number between
- Examples
random()outputs0.483(random decimal)random(20)outputs6(random integer)random("Hello World", "Good morning", "Hello", "Hi")outputsHello(randomly selected value)
replace
- Syntax
string replace(string haystack, string needle1, string replacement1[, .., string needleN, string replacementN])
- Returns
- Replaces all the occurrences of
needleinsidehaystackwith its respectivereplacement. Multiple pairs ofneedle/replacementcan be provided in one function call.
- Replaces all the occurrences of
- Regular expressions
- Needles support regular expressions when their value starts and ends with a
/. For example,'/(\s)/'will match all spaces.
- Needles support regular expressions when their value starts and ends with a
- Examples
replace("Hello World", 'World', 'Earth')outputsHello Earthreplace("Hello World", 'World', 'Earth', 'Hello', 'Hi')outputsHi Earthreplace("Hello World", 'World', 'Earth', 'Earth', 'Planet')outputsHello Planet
right
- Syntax
string right(string value, integer length)
- Returns
- Returns the last
lengthcharacters invalue
- Returns the last
- Examples
right("hello world", 4)outputsorld
startsWith
- Syntax
boolean startsWith(string haystack, string needle)
- Returns
- Returns true if
haystackstarts with theneedle
- Returns true if
string
- Syntax
string string(dynamic value)
- Returns
- Returns
valueas a string.
- Returns
substr
- Alias of
mid()
substring
- Alias of
mid()
title
- Syntax
string title(string value)
- Returns
- Returns the
valuebut in its title case format (each word starts with a capitalized letter).
- Returns the
- Examples
lower("Hello there world")outputsHello There World
upper
- Syntax
string upper(string value)
- Returns
- Returns the
valuebut with all upper case letters.
- Returns the
- Examples
lower("Hello World")outputsHELLO WORLD
text
- Alias of
string()
Numeric functions
avg
- Syntax
decimal avg(decimal value1, decimal value2[, .., decimal valueN])
- Returns
- Returns the mean average of all the values provided.
ceil
- Syntax
integer ceil(decimal value)
- Returns
- Returns the immediately higher integer, equivalent to rounding the decimal away from zero.
- Examples
ceil(5.6)outputs6ceil(-5.6)outputs-6
ceiling
- Alias of
ceil
decimal
- Syntax
decimal decimal(dynamic value)
- Returns
- Converts
valueinto a decimal. Returns0ifvalueis not numeric.
- Converts
float
- Alias of
decimal
floor
- Syntax
integer ceil(decimal value)
- Returns
- Returns the integer part of a decimal, equivalent to rounding the decimal towards zero.
- Examples
floor(5.6)outputs5floor(-5.6)outputs-5
max
- Syntax
dynamic max(dynamic value1, dynamic value2[, .., dynamic valueN])
- Returns
- Returns the maximum of all the values provided. Note: this function works with both numbers and strings.
median
- Syntax
dynamic median(dynamic value1, dynamic value2[, .., dynamic valueN])
- Returns
- Returns the median average of all the values provided. Note: this function works with both numbers and strings.
min
- Syntax
dynamic min(dynamic value1, dynamic value2[, .., dynamic valueN])
- Returns
- Returns the minimum of all the values provided. Note: this function works with both numbers and strings.
number
- Alias of
decimal
power
- Syntax
decimal power(decimal value, decimal exponent)
- Returns
- Returns the
valueat the power ofexponent
- Returns the
round
- Syntax
decimal round(decimal value[, integer precision = 0])
- Arguments
precision- the number of decimal places to be retained. If not provided, defaults to0
- Returns
- Returns the rounded
valuewithprecisiondecimal places.
- Returns the rounded
sqr
- Syntax
decimal sqr(decimal value)
- Returns
- Returns the squared
value, equivalent tovaluemultiplied by itself.
- Returns the squared
sqrt
- Syntax
decimal sqrt(decimal value)
- Returns
- Returns the square root of
value.
- Returns the square root of
stdev
- Syntax
decimal stdev(decimal value1, decimal value2[, .., decimal valueN])
- Returns
- Returns the standard deviation of all the values provided.
sum
- Syntax
decimal sum(decimal value1, decimal value2[, .., decimal valueN])
- Returns
- Returns the sum of sum of all the values provided.
variance
- Syntax
decimal variance(decimal value1, decimal value2[, .., decimal valueN])
- Returns
- Returns the variance of all the values provided.
Boolean functions
bool
- Syntax
bool(dynamic value)
- Returns
- Returns the truth value of the input. Accepts anything as input and will return true if
valueis either a non-zero number, a non-empty string (with some exceptions, see below), a non-empty device list, a non-empty date/time/datetime
- Returns the truth value of the input. Accepts anything as input and will return true if
boolean
- This is an alias of bool
eq
- Syntax
eq(dynamic value1, dynamic value2)
- Returns
- Returns true if
value1is equivalent tovalue2
- Returns true if
ge
- Syntax
ge(dynamic value1, dynamic value2)
- Returns
- Returns true if
value1is greater than or equal tovalue2
- Returns true if
gt
- Syntax
gt(dynamic value1, dynamic value2)
- Returns
- Returns true if
value1is greater thanvalue2
- Returns true if
isBetween
- Syntax
isBetween(dynamic value, dynamic startValue, dynamic endValue)
- Returns
- Returns true if
valueis greater then or equal tostartValueand less than or equal toendValue
- Returns true if
isEmpty
- Syntax
isEmpty(dynamic value)
- Returns
- Returns true if
valueis not set, an empty string, or zero
- Returns true if
le
- Syntax
le(dynamic value1, dynamic value2)
- Returns
- Returns true if
value1is less than or equal tovalue2
- Returns true if
lt
- Syntax
lt(dynamic value1, dynamic value2)
- Returns
- Returns true if
value1is less thanvalue2
- Returns true if
not
- Syntax
not(dynamic value)
- Returns
- Returns the negated truth state of
value. This is the logical negation ofbool(dynamic value).
- Returns the negated truth state of
Date and time functions
addDays
- Syntax
addDays(datetime value, integer days)
- Returns
- Returns a datetime that is
daysdays after thevalue. For negative values ofdays, it returns a datetime that isdaysdays beforevalue.
- Returns a datetime that is
addHours
- Syntax
addHours(datetime value, integer hours)
- Returns
- Returns a datetime that is
hourshours after thevalue. For negative values ofhours, it returns a datetime that ishourshours beforevalue.
- Returns a datetime that is
addMinutes
- Syntax
addMinutes(datetime value, integer minutes)
- Returns
- Returns a datetime that is
minutesminutes after thevalue. For negative values ofminutes, it returns a datetime that isminutesminutes beforevalue.
- Returns a datetime that is
addSeconds
- Syntax
addSeconds(datetime value, integer seconds)
- Returns
- Returns a datetime that is
secondsseconds after thevalue. For negative values ofseconds, it returns a datetime that issecondsseconds beforevalue.
- Returns a datetime that is
addWeeks
- Syntax
addWeeks(datetime value, integer weeks)
- Returns
- Returns a datetime that is
weeksweeks after thevalue. For negative values ofweeks, it returns a datetime that isweeksweeks beforevalue.
- Returns a datetime that is
date
- Syntax
date(datetime value)
- Returns
- Returns the date portion of
valueby stripping off time information.
- Returns the date portion of
datetime
- Syntax
datetime datetime(dynamic value)
- Returns
- Tries to convert any value into a datetime. Accepts strings in common date/time formats.
formatDuration
- Syntax
string formatDuration(datetime value[, boolean friendly = false[, string granularity = 's'[, boolean showAdverbs = false]]])
- Arguments
friendly-falsemakes the output compact, in the form of0d 00:00:00.000, whiletruemakes the output more human friendly, in the form of0 days, 0 hours, 0 minutes, and 0 seconds. Defaults tofalse.granularity- represents the smallest time unit to be output. One ofdfor days,hfor hours,mfor minutes,sfor seconds, ormsfor milliseconds. Any time unit below the selected granularity will not be output. Defaults tosshowAdverbs- only affects the friendly output, whentruethe wordsin(for future durations - positive input) orago(for past durations - negative input) are prepended or appended respectively to the output
- Returns
- Returns a string that represents the duration in a human readable format
- Examples
formatDuration(12029)will output00:00:12formatDuration(68493, true)will output1 minute and 8 secondsformatDuration(68493, false, 'ms')will output00:01:08formatDuration(68493, true, 'm', true)will outputin 1 minute
time
- Syntax
time time(datetime value)
- Returns
- Returns the time portion of
valueby stripping off date information.
- Returns the time portion of
celsius
- Syntax
decimal celsius(decimal value)
- Returns
- Converts a temperature value from Fahrenheit to Celsius.
dewPoint
- Syntax
decimal dewPoint(decimal temperature, decimal relativeHumidity[, string scale = 'F'])
- Parameters
scale- optional, one ofCorF, corresponding to the temperature range used fortemperature. The result will be provided in the same scale. If no scale is provided, the Fahrenheit scale will be used.
- Returns
- Returns the due temperature for a given temperature and relative humidity
fahrenheit
- Syntax
decimal fahrenheit(decimal value)
- Returns
- Converts a temperature value from Celsius to Fahrenheit.
Dynamic
- if(condition, valueIfTrue, valueIfFalse)
- evaluates a boolean and returns value1 if true, or value2 otherwise
- least(values)
- returns the value that is least found a series of numeric values
- most(values)
- returns the value that is most found a series of numeric values
- previousValue([device;attribute])
- returns the previous value of the attribute
Integers
- age([device﹕attribute])
- returns the number of milliseconds an attribute had the current value
- count(values)
- calculates the number of true/non-zero/non-empty items in a series of numeric values
- int()
- //todo
- integer(decimal or string)
- converts a decimal value to it's integer value
- newer([device﹕attribute],[...], [device﹕attribute], threshold)
- returns the number of devices whose attribute had the current value for less than the specified number of milliseconds
- older([device﹕attribute],[...], [device﹕attribute], threshold)
- returns the number of devices whose attribute had the current value for more than the specified number of milliseconds
- previousAge([device﹕attribute])
- returns the number of milliseconds an attribute had the previous value
Time
- time(value)
- returns the value as a time type
- addSeconds(dateTime, seconds)
- adds seconds to time, returns the value as a time type
- addMinutes(dateTime, minutes)
- adds minutes to time, returns the value as a time type
- addHours(dateTime, hours)
- adds hours to time, returns the value as a time type
- addDays(dateTime, days)
- adds days to time, returns the value as a time type
- addWeeks(dateTime, weeks)
- adds weeks to time, returns the value as a time type
