a!customFieldSubtract( value1, value2 )
Used to create a realtime custom record field, this function returns the difference between two numbers. You can subtract record fields, related record fields, or literal values of type Number (Integer) or Number (Decimal).
Keyword  Type  Description 


Any Type 
The record field, related record field, or literal value from which value2 is subtracted. Valid data types include Number (Integer) or Number (Decimal). 

Any Type 
The record field, related record field, or literal value to subtract. Valid data types include Number (Integer) or Number (Decimal). 
The a!customFieldSubtract()
function can only be used to create a custom record field that evaluates in real time. This means you can reference related record fields, constants, and other supported functions in your calculations.
To create a custom record field that evaluates in realtime:
Enter an expression using any Custom Field function.
Custom record fields that evaluate in realtime must use at least one Custom Field function.
You can use the a!customFieldSubtract()
function in conjunction with other Custom Field functions, like a!customFieldSum(), a!customFieldDivide(), or a!customFieldMultiply() to create the calculations you need.
See the Realtime evaluation recipes for an example.
Let's say you want calculate each employee's net salary.
The Employee record type has a grossSalary
field, which contains each employee's salary amount. The Benefits record type has a deductions
field, which determines the deduction amount based on the selected benefits plan.
To calculate each employee's net salary, you could create a custom record field on the Employee record type that evaluates in realtime so you can reference the related record field from the Benefits record type in your calculation.
The expression would look something like this:
1
2
3
4
a!customFieldSubtract(
value1: recordType!Employee.fields.grossSalary,
value2: recordType!Employee.relationships.benefits.fields.deductions
)
You can use any of the following supported functions in either parameter of a!customFieldSubtract()
. However, you must reference a record field, related record field, or another Custom Field function in at least one parameter.
When you use a supported function in a Custom Field function, you can only pass static values or constants containing static values into the supported function; you cannot pass record field references.
Category  Function  Description 

Array  a!flatten()  Converts an array that contains other arrays into an array of single items. 
Array  a!update()  Inserts new values or replaces existing values at the specified index or field name and returns the resulting updated data. 
Array  append()  Appends a value or values to the given array, and returns the resulting array. 
Array  index()  Returns the data[index] if it is valid or else returns the default value. 
Array  insert()  Inserts a value into the given array and returns the resulting array. 
Array  joinarray()  Concatenates the elements of an array together into one string and inserts a string separator between each element. 
Array  ldrop()  Drops a given number of values from the left side of an array and returns the resulting array. 
Array  length()  This function returns the number of elements in an array. 
Array  rdrop()  Drops a given number of values from the right side of an array, and returns the resulting array. 
Array  remove()  Removes the value at a given index from an array, and returns the resulting array. 
Array  reverse()  Returns an array in reverse order. 
Array  updatearray()  Inserts new values or modifies existing values at the specified index of a given array, and returns the resulting array. 
Array  where()  Returns the indexes where the values in the input array are true. 
Array  wherecontains()  Receives one or more values and returns an array of indexes that indicate the position of the values within the array. 
Base Conversion  bin2dec()  Converts a Binary number as text to a Decimal number. 
Base Conversion  bin2hex()  Converts a Binary number as text to a Hex number as text. 
Base Conversion  bin2oct()  Converts a Binary number as text to an Octal number as text. 
Base Conversion  dec2bin()  Converts a Decimal number to a Binary number as text. 
Base Conversion  dec2hex()  Converts a Decimal number to a Hex number as text. 
Base Conversion  dec2oct()  Converts a Decimal number to an Octal number as text. 
Base Conversion  hex2bin()  Converts a Hex number as text to a Binary number as text. 
Base Conversion  hex2dec()  Converts a Hex number as text to a Decimal number. 
Base Conversion  hex2oct()  Converts a Hex number as text to an Octal number as text. 
Base Conversion  oct2bin()  Converts an Octal number as text to a Binary number as text. 
Base Conversion  oct2dec()  Converts an Octal number as text to a Decimal number. 
Base Conversion  oct2hex()  Converts an Octal number as text to a Hex number as text. 
Conversion  displayvalue()  Tries to match a value in a given array with a value at the same index in a replacement array and returns either the value at the same index or a default value if the value is not found. 
Conversion  externalize()  Converts the given value to a string representation so that it can be saved externally. 
Conversion  toboolean()  Converts a value to Boolean. 
Conversion  todate()  Converts a value to Date with Timezone. 
Conversion  todatetime()  Converts a value to Date and Time with Timezone. 
Conversion  todecimal()  Converts a value to Decimal (doubleprecision floatingpoint number). 
Conversion  toemailaddress()  Converts a value to email address. 
Conversion  tointeger()  Converts a value to Integer. 
Conversion  tointervalds()  Converts a value to Interval (Day to Second). 
Conversion  tostring()  Converts a value to Text. 
Conversion  totime()  Converts a value to Time. 
Conversion  touniformstring()  Converts a value or list to text, preserving the original scalar or array structure. 
Date and Time  a!addDateTime()  Adds the specified increments of time to the startDateTime and returns a date and time value. You can select a process calendar to ensure the return value falls within the specified working days and time. 
Date and Time  calisworkday()  This returns whether or not the given Date and Time is a work day, according to the calendar defined for the system. 
Date and Time  calisworktime()  This returns whether or not the given Date and Time is within working hours, according to the calendars defined for the system. 
Date and Time  calworkdays()  This returns the actual number of work days between two Date and Times (both inclusive), according to the calendar defined for the system. 
Date and Time  calworkhours()  This returns the actual number of work hours between two given Date and Times (both inclusive), according to the calendar defined for the system. 
Date and Time  date()  Converts text into data accepted by the date data type and functions that require date parameters. 
Date and Time  datetime()  Converts the given Date and Time into a serial number that holds the Date and Time data type. 
Date and Time  datevalue()  Converts a value to a date. 
Date and Time  day()  Returns the day of the month from the date specified. 
Date and Time  dayofyear()  Returns the day number within the year. 
Date and Time  days360()  Returns the number of days between two dates, based on a 360day calendar. 
Date and Time  daysinmonth()  Returns the number of days in the given month in the given year. 
Date and Time  edate()  Returns the date that is the number of months before or after the given starting date. 
Date and Time  eomonth()  Returns the date for the last day of the month that is the number of months before or after the given starting date. 
Date and Time  gmt()  Subtracts a time zone offset from a given Date and Time. 
Date and Time  hour()  Returns the hour from the time specified. 
Date and Time  intervalds()  Converts the given time components into an equivalent time duration, an interval expressing days to seconds. This value is treated as a duration (Joe ran the marathon in 3 hours and 23 minutes), not a point in time. 
Date and Time  isleapyear()  Returns a Boolean value for whether the given year is a leap year. 
Date and Time  lastndays()  Returns a Boolean value for whether the given date is within the last given number of days. 
Date and Time  local()  This is a Date and Time addition function, adding time zone offset to given Date and Time. 
Date and Time  milli()  This function returns the millisecond portion of a timestamp or the decimal number that represents 1 millisecond in days. 
Date and Time  minute()  Returns the minute from the time specified. 
Date and Time  month()  Returns the month from the specified date. 
Date and Time  networkdays()  Returns the number of working days between two specified dates. 
Date and Time  now()  Returns the current Date and Time as a serial number. 
Date and Time  second()  Returns the seconds from the specified time. 
Date and Time  a!subtractDateTime()  Subtracts the specified increments of time from the startDateTime and returns a date and time value. You can select a process calendar to ensure the return value falls within the specified working days and time. 
Date and Time  time()  Converts the given time into an equivalent time value. 
Date and Time  timevalue()  Converts the given time into an equivalent interval. 
Date and Time  timezone()  Returns the default offset in minutes from GMT, which is generally the process initiator's time zone. 
Date and Time  timezoneid()  Returns the time zone ID for the current context. 
Date and Time  today()  Returns the current day in GMT. 
Date and Time  weekday()  Returns the day of the week of the specified date. 
Date and Time  weeknum()  Returns the week number within the year for the given date using a given methodology. 
Date and Time  workday()  Returns the date the given number of workdays before or after the given date. 
Date and Time  year()  Returns the year for the date specified. 
Date and Time  yearfrac()  Determine the fraction of the year. 
Informational  a!defaultValue()  Returns a default value when the specified value is null or empty. When there are multiple default parameters, each parameter is evaluated in order and the first nonnull and nonempty default will be returned. 
Informational  a!keys()  Returns the keys of the provided map, dictionary, CDT, or record. 
Informational  a!listType()  Returns the list type number for a given type number. 
Informational  cast()  Converts a value from its existing type to the specified type. 
Informational  error()  Raises an error with the given message, used for invalidating execution.This function never returns a value. 
Informational  infinity()  Represents a constant number that stands for positive infinity or a negative infinity if you negate the value. 
Informational  isinfinite()  Tests given numbers against positive and negative infinity, returning 
Informational  isnegativeinfinity()  Tests given numbers against negative infinity, returning true if number is negative infinity, false if number is not negative infinity. 
Informational  a!isNotNullOrEmpty()  Returns 
Informational  isnull()  Returns true if value is null, false otherwise. 
Informational  a!isNullOrEmpty()  Returns 
Informational  ispositiveinfinity()  Tests given numbers against positive infinity, returning 
Informational  nan()  Constant number representing Not A Number, generally used for comparison to the result of mathematical operations with invalid inputs. This is equivalent to a decimal (floating point) null, but nan() is provided for more explicit usage in mathematical expressions. 
Informational  null()  Returns a null value. 
Informational  runtimetypeof()  Returns the numerical representation of an Appian system data type when used during process execution. 
Informational  typename()  Returns the type name of a given type number. 
Informational  typeof()  Returns the type number of a given value. 
Logical  and()  Returns 
Logical  choose()  Evaluates the 
Logical  false()  Returns the Boolean value 
Logical  if()  Returns 
Logical  not()  Converts 
Logical  or()  Returns 
Logical  true()  Returns the Boolean value 
Looping  a!forEach()  Evaluates an expression for each item in a list and returns a new array of the results. 
Looping  all()  Calls a rule or function that returns either true or false for each item in list, asks the question, "Do all items in this list yield true for this rule/function?", and returns true if all items in list evaluates to true. 
Looping  any()  Calls a rule or function that returns either true or false for each item in list by asking the question, "Do any items in this list yield true for this rule/function?" with the intent to discover if any item(s) yield true. 
Looping  apply()  Calls a rule or function for each item in a list, and provides any contexts specified. 
Looping  filter()  Calls a predicate for each item in a list and returns any items for which the returned value is true. 
Looping  merge()  Takes a variable number of lists and merges them into a single list (or a list of lists) that is the size of the largest list provided. 
Looping  none()  Calls a rule or function that returns either true or false for each item in list by asking the question, "Do all items in this list yield false for this rule/function?" with the intent to discover if no items will yield true. 
Looping  reduce()  Calls a rule or function for each item in a list, passing the result of each call to the next one, and returns the value of the last computation. 
Looping  reject()  Calls a predicate for each item in a list, rejects any items for which the returned value is true, and returns all remaining items. 
Mathematical  abs()  Returns the absolute value(s) of the specified number(s). 
Mathematical  ceiling()  Rounds the number up to the nearest multiple of the specified significance. 
Mathematical  combin()  Calculates the number of unique ways to choose m elements from a pool of n elements. 
Mathematical  a!distanceBetween()  Returns the distance between the two locations (in meters) specified by the start and end coordinates. The distance is calculated by tracing a line between the two locations that follows the curvature of the Earth, and measuring the length of the resulting arc. 
Mathematical  e()  Returns the value of e. 
Mathematical  enumerate()  Returns a list of integer numbers from 0 through n1. 
Mathematical  even()  Rounds positive numbers up to nearest even integer and negative numbers down to the nearest even integer. 
Mathematical  exp()  Returns e raised to the specified power. 
Mathematical  fact()  The factorial of specified number. 
Mathematical  factdouble()  The double factorial of specified number (mathematically n!!). 
Mathematical  floor()  Rounds the number down to the nearest multiple of the specified significance. 
Mathematical  int()  Rounds the specified number down to the nearest integer. 
Mathematical  ln()  Returns the natural logarithm of the specified number, which is the power that e must be raised to in order to equal the specified number. 
Mathematical  log()  Returns the logarithm of the number using the specified base, which is the power that base must be raised to, to equal the number. 
Mathematical  mod()  Returns the remainder of dividend when divided by the divisor. 
Mathematical  mround()  Rounds the number to the specified multiple. 
Mathematical  multinomial()  Adds the specified integers and divides the factorial of the sum by the factorial of the individual numbers. 
Mathematical  odd()  Rounds positive numbers up to nearest odd integer and negative numbers down to the nearest odd integer. 
Mathematical  pi()  Returns the value of pi. 
Mathematical  power()  Returns the base number raised to the specified exponent. 
Mathematical  product()  Returns the product of the specified numbers. 
Mathematical  quotient()  Returns the quotient when numerator is divided by the denominator, and drops the remainder. 
Mathematical  rand()  Returns a random number between 0 and 1 based on an even probability distribution, which is seeded by the transaction time. 
Mathematical  round()  Rounds off the number to the specified number of digits. 
Mathematical  rounddown()  Rounds the number down to the specified digit. 
Mathematical  roundup()  Rounds the number up to the specified digit. 
Mathematical  sign()  Returns the number divided by its absolute value, which is 1 if the number is positive and 1 if the number is negative. 
Mathematical  sqrt()  Returns the square root(s) of the specified number(s). 
Mathematical  sqrtpi()  Multiplies the number by pi, then returns the square root of the product. 
Mathematical  sum()  Returns the sum of the specified numbers. 
Mathematical  sumsq()  Squares each number and then returns the sum of the squares. 
Mathematical  trunc()  Truncates a decimal number to the specified number of places after the decimal point. 
Scripting  offsetFromGMT()  Returns the offset (in minutes) from GMT of the given date and timezone. 
Scripting  property()  This function extracts a bean's property under a given key name (the 
Array  contains()  Checks whether an array contains the value. 
Array  difference()  Returns the values in array1 and not in array2. 
Array  intersection()  Returns only those elements that appear in all of the given arrays. 
Array  symmetricdifference()  Returns the values from two integer arrays that are not in both arrays. 
Array  union()  Returns all unique elements from the given arrays. 
System  a!jsonPath()  Finds information in a JSON string. JSONPath is used to navigate through elements and attributes in a JSON string. 
System  a!map()  Creates a map of values (Any Type) with each value stored at the corresponding string key. Values stored in maps are not wrapped in variants. 
Text  char()  Converts a number into its Unicode character equivalent. 
Text  charat()  Returns the character at given index within specified string. 
Text  clean()  Returns the specified text, minus any characters not considered printable. Printable characters are the 95 printable ASCII characters plus three special characters: BACKSPACE (0x08), TAB (0x09), and NEWLINE (0x0a). 
Text  cleanwith()  Returns the specified text, minus any characters not in the list of valid characters. 
Text  code()  Converts the text into Unicode integers. 
Text  concat()  Concatenates the specified strings into one string, without a separator. 
Text  exact()  Compares two given text strings in a casesensitive manner, returning true only if they are exactly the same. 
Text  extract()  Returns the value (or values, if the text contains multiple delimited values) between the delimiters from the given text. 
Text  extractanswers()  Returns an array of strings that respond to the questions provided. 
Text  find()  Searches the text for a particular substring, returning the positional index of the first character of the first match. 
Text  fixed()  Rounds the specified number off to a certain number of decimals and returns it as text, with optional commas. 
Text  a!formatPhoneNumber()  Returns a formatted phone number based on the outputFormat parameter. The countryCode parameter, or any country code provided in the phone number, will verify that the phone number is valid. If the phone number does not match any provided country code, the phone number will be returned as invalid and unformatted. 
Text  initials()  Returns only the uppercase characters from within the given text. 
Text  insertkey()  Returns the provided text, wrapped with the specified delimiters. 
Text  insertkeyval()  Returns the provided keyvalue pairs, wrapped with the specified delimiters. 
Text  insertquestions()  Returns an array of questions with a ==EOQ== at the end, returning a single string that can be parsed with 
Text  a!isPhoneNumber()  Returns true if the phoneNumber parameter contains a valid phone number, otherwise returns false. A phone number is considered valid if its area code is valid, the length is appropriate based upon the value of the countryCode parameter, and the number after the area code is not all zeroes. This function supports countries and area codes for international numbers. 
Text  keyval()  Returns the value(s) associated with the given key(s). 
Text  left()  Returns a specified number of characters from the text, starting from the first character. 
Text  leftb()  Returns a specified number of bytes from the text, starting from the first byte. 
Text  len()  Returns the length in characters of the text. 
Text  lenb()  Returns the length in bytes of the text. 
Text  like()  Tests whether a string of text is like a given pattern. 
Text  lower()  Converts all characters in the text into lowercase (Unicode case folding). 
Text  mid()  Returns a substring from the middle of the specified text. 
Text  midb()  Returns a substring from the middle of the specified text. 
Text  padleft()  Pads text with spaces on the left so that it is a certain length. 
Text  padright()  Pads text with spaces on the right so that it is a certain length. 
Text  proper()  Converts each character in the text into proper case, meaning it will capitalize the first first letter of every word and convert the rest into lowercase. 
Text  replace()  Replaces a piece of the specified text with new text. 
Text  replaceb()  Replaces a piece of the specified text with new text. 
Text  rept()  Concatenates the text to itself a specified number of times and returns the result. 
Text  resource()  Retrieves a string of translated text appropriate for the current user, according to their language preference, by matching a given key with text. 
Text  right()  Returns a specified number of characters from the text, starting from the last character. 
Text  search()  Searches the text for the given, case insensitive substring. Returns the onebased positional index of the first character of the first match. Returns zero if the substring is not found. 
Text  searchb()  Searches the text for a particular substring, returning the positional index of the first byte of the first match. 
Text  soundex()  Returns the soundex code, used to render similar sounding names via phonetic similarities into identical four (4) character codes. 
Text  split()  Splits text into a list of text elements, delimited by the text specified in the separator. 
Text  strip()  Returns the provided text, minus any characters considered printable. Printable characters are the 95 printable ASCII characters plus three special characters: BACKSPACE (0x08), TAB (0x09), and NEWLINE (0x0a). 
Text  stripHtml()  Changes the provided HTML string into a plain text string by converting 
Text  stripwith()  The function returns the provided text, minus any characters on the list of invalid characters. 
Text  substitute()  Substitutes a specific part of a string with another string. 
Text  toHtml()  Converts a string in plain text to the HTML equivalent that displays appropriately in an HTML page, by replacing reserved characters with their escaped counterparts. 
Text  trim()  Removes all unnecessary spaces from the text. 
Text  upper()  Converts all letters in the text into uppercase. 
Text  value()  Converts text representing a number into an actual number or datetime. 
Trigonometry  acos()  Returns the arccosine(s) of the specified number(s) in radians. 
Trigonometry  acosh()  Returns the hyperbolic arccosine(s) of the specified number(s) in radians. 
Trigonometry  asin()  Returns the arcsine(s) of the specified number(s) in radians. 
Trigonometry  asinh()  Returns the hyperbolic arcsine(s) of the specified number(s) in radians. 
Trigonometry  atan()  Returns the arctangent(s) of the specified number(s) in radians. 
Trigonometry  atanh()  Returns the hyperbolic arctangent(s) of the specified number(s) in radians. 
Trigonometry  cos()  Returns the cosine(s) of the specified number(s). 
Trigonometry  cosh()  Returns the hyperbolic cosine(s) of the specified number(s). 
Trigonometry  degrees()  Converts the measure(s) of the specified angle(s) from radians to degrees. 
Trigonometry  radians()  Converts the measure of the specified angle from degrees to radians. 
Trigonometry  sin()  Returns the sine(s) of the specified number(s). 
Trigonometry  sinh()  Returns the hyperbolic sine(s) of the specified number(s). 
Trigonometry  tan()  Returns the tangent(s) of the specified number(s). 
Trigonometry  tanh()  Returns the hyperbolic tangent(s) of the specified number(s). 
Feature  Compatibility  Note 

Portals  Partially compatible  Can be used with Appian Portals if it is connected using an integration and web API. 
Offline Mobile  Incompatible  
SyncTime Custom Record Fields  Incompatible  
RealTime Custom Record Fields  Compatible  Can only be used to create a custom record field that evaluates in real time. It cannot be used anywhere else in your application. 
Process Reports  Incompatible  Cannot be used to configure a process report. 
Process Events  Incompatible  Cannot be used to configure a process event node, such as a start event or timer event. 