# Operators Operator expressions are similar to functions that take arguments. | abs | `$abs` | Returns the absolute value of a number | | ---------------- | ------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | acos | `$acos` | Returns a numeric value between 0 and π radians for x between -1 and 1 | | acosh | `$acosh` | Returns the inverse hyperbolic cosine of a number | | acl | `$acl` | Not applicable | | add | `$add` | Adds two or more array properties or expressions. In addition to numbers, a single Date value may be included in the array. | | and | `$and` | Evaluates to **true** if all conditions in the passed in array evaluate to true | | asin | `$asin` | Returns the arcsine (in radians) of a number | | asinh | `$asinh` | Returns the hyperbolic arcsine of a number | | atan | `$atan` | Returns the arctangent (in radians) of a number | | atan2 | `$atan2` | Returns the angle in the plane (in radians) between the positive x-axis and the ray from (0,0) to the point (x,y) | | atanh | `$atanh` | Returns the hyperbolic arctangent of a number | | ceil | `$ceil` | Always rounds a number up to the next largest integer | | convert | `$convert` | Not applicable | | cos | `$cos` | Returns the cosine of the specified angle, which must be specified in radians | | dateFromParts | `$dateFromParts` | Returns a date from the specified parts (year, month, and day values) | | dateFromString | `$dateFromString` | Converts a date object to a string in a specified format, and expects an array of \[date\_expression] | | dateToParts | `$dateToParts` | Returns a document that contains the constituent parts of a given Date value as individual properties | | dateToString | `$dateToString` | Converts a date object to a string according to a user-specified format | | dayOfMonth | `$dayOfMonth` | Returns the day of the month for a date as a number between 1 and 31 | | dayOfWeek | `$dayOfWeek` | Returns the day of the week for a date as a number between 1 (Sunday) and 7 (Saturday) | | dayofYear | `$dayofYear` | Returns the day of the year for a date as a number between 1 and 366 | | degreestoRadians | `$degreestoRadians` | Converts an input value measured in degrees to radians | | divide | `$divide` | Divides one number by another and returns the result | | exp | `$exp` | Takes the e^n of a number | | floor | `$floor` | Returns the largest integer less than or equal to the specified number | | hour | `$hour` | Returns the hour portion of a date as a number between 0 and 23 | | isoDayOfWeek | `$isoDayOfWeek` | Returns the weekday number in ISO 8601 format, ranging from 1 (Monday) to 7 (Sunday) | | isoWeek | `$isoWeek` | Returns the week number in ISO 8601 format, ranging from 1 to 53 | | isoWeekYear | `$isoWeekYear` | Returns the year number in ISO 8601 format | | log | `$log` | Takes the log of the first number in the second number's base | | log10 | `$log10` | Calculates the log base 10 of a number and returns the result as a double | | let | `$let` |

Binds variables for use in the specified expression, and returns the result of the expression

View let for more information on how the let variable is used in mongodb operations.

| | ltrim | `$ltrim` | Removes whitespace characters, including null, or the specified characters from the beginning of a string | | mergeObjects | `$mergeObjects` | Combines multiple documents into a single document | | milliseconds | `$milliseconds` | Returns the millisecond portion of a date as an integer between 0 and 999 | | minute | `$minute` | Returns the minute portion of a date as a number between 0 and 59 | | moment | `$moment` |

Used as a wrapper for the moment.js library to parse, validate, manipulate, and display dates and times in JavaScript

Example to determine the difference between two dates:

$moment: \[date, { 'diff': \[date2, 'days'] }]

| | month | `$month` | Returns the month of a date as a number between 1 and 12 | | multiply | `$multiply` | Multiplies the value of a field by a number | | omit | `$omit` | Not applicable | | or | `$or` | Performs a logical OR operation on an array of two or more and selects the documents that satisfy at least one of the arguments | | pathTo | $pathTo |

Sets a path and creates deep objects

Example:
$pathTo: \[{ $literal: {} }, 'configuration.reporting.enabled', true]

| | pick | `$pick` | Not applicable | | radiansToDegrees | `$radiansToDegrees` | Converts an input value measured in radians to degrees | | regexFind | `$regexFind` | Provides regular expression (regex) pattern matching capability in aggregation expressions | | regexFindAll | `$regexFindAll` | Provides regex pattern matching capability in aggregation expressions. The operator returns an array of documents that contains information on each match. | | regexMatch | `$regexMatch` | Performs regex pattern matching and returns | | replaceAll | `$replaceAll` | Replaces all instances of a search string in an input string with a replacement string | | replaceOne | `$replaceOne` | Replaces the first instance of a search string in an input string with a replacement string | | rtrim | `$rtrim` | Removes whitespace characters, including null, or the specified characters from the end of a string | | second | `$second` | Returns the second portion of a date as a number between 0 and 59, but can be 60 to account for leap seconds | | sin | `$sin` | Returns the sine of a value that is measured in radians | | split | `$split` | Divides a string into an array of substrings based on a delimiter | | sqrt | `$sqrt` | Calculates the square root of a positive number and returns the result as a double | | stdDevPop | `$stdDevPop` | Calculates the population standard deviation of the input values | | stdDevSamp | `$stdDevSamp` | Calculates the sample standard deviation of the input values | | strcasecmp | `$strcasecmp` | Performs a case-insensitive comparison of two strings | | strLenBytes | `$strLenBytes` | Returns the number of UTF-8 encoded bytes in the specified string | | strLenCP | `$strLenCP` | Returns the number of UTF-8 code points in the specified string | | substr | `$substr` | Returns the number of UTF-8 encoded bytes in the specified string | | substrBytes | `$substrBytes` | Returns the substring of a string | | substrCP | `$substrCP` | Returns the substring of a string | | tan | `$tan` | Returns the tangent of a value that is measured in radians | | toDate | `$toDate` | Converts a value to date | | toLower | `$toLower` | Converts a string to lowercase, returning the result | | toUpper | `$toUpper` | Converts a string to uppercase, returning the result | | trim | `$trim` | Removes whitespace characters, including null, or the specified characters from the beginning and end of a string | | week | `$week` | Returns the week of the year for a date as a number between 0 and 53 | | year | `$year` | Returns the year portion of a date | --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.medable.com/cortex-api/expressions/operators.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.