Stream evaluators are different then stream sources or stream decorators. Both stream sources and stream decorators return streams of tuples. Stream evaluators are more like a traditional function that evaluates its parameters and returns an result. That result can be a single value, array, map or other structure.
Stream evaluators can be nested so that the output of an evaluator becomes the input for another evaluator.
Stream evaluators can be called in different contexts. For example a stream evaluator can be called on its own or it can be called within the context of a streaming expression.
abs
The abs
function will return the absolute value of the provided single parameter. The abs
function will fail to execute if the value is non-numeric. If a null value is found then null will be returned as the result.
abs Parameters
-
Field Name | Raw Number | Number Evaluator
abs Syntax
The expressions below show the various ways in which you can use the abs
evaluator. Only one parameter is accepted. Returns a numeric value.
abs(1) // 1, not really a good use case for it
abs(-1) // 1, not really a good use case for it
abs(add(fieldA,fieldB)) // absolute value of fieldA + fieldB
abs(fieldA) // absolute value of fieldA
acos
The acos
function returns the trigonometric arccosine of a number.
acos Parameters
-
Field Name | Raw Number | Number Evaluator
: The value to return the arccosine of.
acos Syntax
acos(100.4) // returns the arccosine of 100.4
acos(fieldA) // returns the arccosine for fieldA.
if(gt(fieldA,fieldB),sin(fieldA),sin(fieldB)) // if fieldA > fieldB then return the arccosine of fieldA, else return the arccosine of fieldB
add
The add
function will take 2 or more numeric values and add them together. The add
function will fail to execute if any of the values are non-numeric. If a null value is found then null will be returned as the result.
add Parameters
-
Field Name | Raw Number | Number Evaluator
-
Field Name | Raw Number | Number Evaluator
-
……
-
Field Name | Raw Number | Number Evaluator
add Syntax
The expressions below show the various ways in which you can use the add
evaluator. The number and order of these parameters do not matter and is not limited except that at least two parameters are required. Returns a numeric value.
add(1,2,3,4) // 1 + 2 + 3 + 4 == 10
add(1,fieldA) // 1 + value of fieldA
add(fieldA,1.4) // value of fieldA + 1.4
add(fieldA,fieldB,fieldC) // value of fieldA + value of fieldB + value of fieldC
add(fieldA,div(fieldA,fieldB)) // value of fieldA + (value of fieldA / value of fieldB)
add(fieldA,if(gt(fieldA,fieldB),fieldA,fieldB)) // if fieldA > fieldB then fieldA + fieldA, else fieldA + fieldB
analyze
The analyze
function analyzes text using a Lucene/Solr analyzer and returns a list of tokens
emitted by the analyzer. The analyze
function can be called on its own or within the
select
and cartesianProduct
streaming expressions.
analyze Parameters
-
Field Name
|Raw Text
: Either the field in a tuple or the raw text to be analyzed. -
Analyzer Field Name
: The field name of the analyzer to use to analyze the text.
analyze Syntax
The expressions below show the various ways in which you can use the analyze
evaluator.
-
Analyze the raw text:
analyze("hello world", analyzerField)
-
Analyze a text field within a
select
expression. This will annotate the tuples with output of the analyzer:select(expr, analyze(textField, analyzerField) as outField)
-
Analyze a text field with a
cartesianProduct
expression. This will stream each token emitted by the analyzer in its own tuple:cartesianProduct(expr, analyze(textField, analyzer) as outField)
and
The and
function will return the logical AND of at least 2 boolean parameters. The function will fail to execute if any parameters are non-boolean or null. Returns a boolean value.
and Parameters
-
Field Name | Raw Boolean | Boolean Evaluator
-
Field Name | Raw Boolean | Boolean Evaluator
-
……
-
Field Name | Raw Boolean | Boolean Evaluator
and Syntax
The expressions below show the various ways in which you can use the and
evaluator. At least two parameters are required, but there is no limit to how many you can use.
and(true,fieldA) // true && fieldA
and(fieldA,fieldB) // fieldA && fieldB
and(or(fieldA,fieldB),fieldC) // (fieldA || fieldB) && fieldC
and(fieldA,fieldB,fieldC,or(fieldD,fieldE),fieldF)
anova
The anova
function calculates the analysis of variance for two or more numeric arrays.
anova Parameters
-
numeric array
… (two or more)
anova Syntax
anova(numericArray1, numericArray2) // calculates ANOVA for two numeric arrays
anova(numericArray1, numericArray2, numericArray2) // calculates ANOVA for three numeric arrays
array
The array
function returns an array of numerics or other objects including other arrays.
array Parameters
-
numeric
|array
…
array Syntax
array(1, 2, 3) // Array of numerics
array(array(1,2,3), array(4,5,6)) // Array of arrays
asin
The asin
function returns the trigonometric arcsine of a number.
asin Parameters
-
Field Name | Raw Number | Number Evaluator
: The value to return the arcsine of.
asin Syntax
asin(100.4) // returns the sine of 100.4
asine(fieldA) // returns the sine for fieldA.
if(gt(fieldA,fieldB),asin(fieldA),asin(fieldB)) // if fieldA > fieldB then return the asine of fieldA, else return the asine of fieldB
atan
The atan
function returns the trigonometric arctangent of a number.
atan Parameters
-
Field Name | Raw Number | Number Evaluator
: The value to return the arctangent of.
atan Syntax
atan(100.4) // returns the arctangent of 100.4
atan(fieldA) // returns the arctangent for fieldA.
if(gt(fieldA,fieldB),atan(fieldA),atan(fieldB)) // if fieldA > fieldB then return the arctanget of fieldA, else return the arctangent of fieldB
betaDistribution
The betaDistribution
function returns a beta probability distribution
based on its parameters. This function is part of the
probability distribution framework and is designed to work with the sample
, kolmogorovSmirnov
and cumulativeProbability
functions.
betaDistribution Parameters
-
double
: shape1 -
double
: shape2
betaDistribution Returns
A probability distribution function.
betaDistribution Syntax
betaDistribution(1, 5)
binomialCoefficient
The binomialCoefficient
function returns a Binomial Coefficient, the number of k-element subsets that can
be selected from an n-element set.
binomialCoefficient Parameters
-
integer
: [n] set -
integer
: [k] subset
binomialCoefficient Returns
A long value: The number of k-element subsets that can be selected from an n-element set.
binomialCoefficient Syntax
binomialCoefficient(8, 3) // Returns the number of 3 element subsets from an 8 element set.
binomialDistribution
The binomialDistribution
function returns a binomial probability distribution
based on its parameters. This function is part of the probability distribution framework and is designed to
work with the sample
, probability
and cumulativeProbability
functions.
binomialDistribution Parameters
-
integer
: number of trials -
double
: probability of success
binomialDistribution Returns
A probability distribution function.
binomialDistribution Syntax
binomialDistribution(1000, .5)
canberraDistance
The canberraDistance
function calculates the Canberra distance of two numeric arrays.
canberraDistance Parameters
-
numeric array
-
numeric array
canberraDistance Returns
A numeric.
canberraDistance Syntax
canberraDistance(numericArray1, numuericArray2))
cbrt
The cbrt
function returns the trigonometric cube root of a number.
cbrt Parameters
-
Field Name | Raw Number | Number Evaluator
: The value to return the cube root of.
cbrt Syntax
cbrt(100.4) // returns the square root of 100.4
cbrt(fieldA) // returns the square root for fieldA.
if(gt(fieldA,fieldB),cbrt(fieldA),cbrt(fieldB)) // if fieldA > fieldB then return the cbrt of fieldA, else return the cbrt of fieldB
ceil
The ceil
function rounds a decimal value to the next highest whole number.
ceil Parameters
-
Field Name | Raw Number | Number Evaluator
: The decimal to round up.
ceil Syntax
The expressions below show the various ways in which you can use the ceil
evaluator.
ceil(100.4) // returns 101.
ceil(fieldA) // returns the next highest whole number for fieldA.
if(gt(fieldA,fieldB),ceil(fieldA),ceil(fieldB)) // if fieldA > fieldB then return the ceil of fieldA, else return the ceil of fieldB.
chebyshevDistance
The chebyshevDistance
function calculates the Chebyshev distance of two numeric arrays.
chebyshevDistance Parameters
-
numeric array
-
numeric array
chebyshevDistance Returns
A numeric.
chebyshevDistance Syntax
chebyshevDistance(numericArray1, numuericArray2))
col
The col
function returns a numeric array from a list of Tuples. The col
function is used to create numeric arrays from stream sources.
col Parameters
-
list of Tuples
-
field name
: The field to create the array from.
col Syntax
col(tupleList, fieldName)
constantDistribution
The constantDistribution
function returns a constant probability distribution based on its parameter.
This function is part of the probability distribution framework and is designed to
work with the sample
and cumulativeProbability
functions.
When sampled the constant distribution always returns its constant value.
constantDistribution Parameters
-
double
: constant value
constantDistribution Returns
A probability distribution function.
constantDistribution Syntax
constantDistribution(constantValue)
conv
The conv
function returns the convolution of two numeric arrays.
conv Parameters
-
numeric array
-
numeric array
conv Syntax
conv(numericArray1, numericArray2)
copyOf
The copyOf
function creates a copy of a numeric array.
copyOf Parameters
-
numeric array
-
length
: The length of the copied array. The returned array will be right padded with zeros if the length parameter exceeds the size of the original array.
copyOf Syntax
copyOf(numericArray, length)
copyOfRange
The copyOfRange
function creates a copy of a range of a numeric array.
copyOfRange Parameters
-
numeric array
-
start index
-
end index
copyOfRange Syntax
copyOfRange(numericArray, startIndex, endIndex)
corr
The corr
function returns the Pearson Product Moment Correlation of two numeric arrays.
corr Parameters
-
numeric array
-
numeric array
corr Returns
A double between -1 and 1.
corr Syntax
corr(numericArray1, numericArray2)
cos
The cos
function returns the trigonometric cosine of a number.
cos Parameters
-
Field Name | Raw Number | Number Evaluator
: The value to return the hyperbolic cosine of.
cos Syntax
cos(100.4) // returns the arccosine of 100.4
cos(fieldA) // returns the arccosine for fieldA.
if(gt(fieldA,fieldB),cos(fieldA),cos(fieldB)) // if fieldA > fieldB then return the arccosine of fieldA, else return the cosine of fieldB
cosineSimilarity
The cosineSimilarity
function returns the cosine similarity of two numeric arrays.
cosineSimilarity Parameters
-
numeric array
-
numeric array
cosineSimilarity Returns
A numeric.
cosineSimilarity Syntax
cosineSimilarity(numericArray, numericArray)
cov
The cov
function returns the covariance of two numeric arrays.
cov Parameters
-
numeric array
-
numeric array
cov Syntax
cov(numericArray, numericArray)
cumulativeProbability
The cumulativeProbability
function returns the cumulative probability of a random variable within a
probability distribution. The cumulative probability is the total probability of
all random variables less then or equal to a random variable.
cumulativeProbability Parameters
-
probability distribution
-
number
: Value to compute the probability for.
cumulativeProbability Returns
A double: the cumulative probability.
cumulativeProbability Syntax
cumulativeProbability(normalDistribution(500, 25), 502) // Returns the cumulative probability of the random sample 502 in a normal distribution with a mean of 500 and standard deviation of 25.
describe
The describe
function returns a tuple containing the descriptive statistics for an array.
describe Parameters
-
numeric array
describe Syntax
describe(numericArray)
distance
The distance
function calculates the Euclidian distance of two numeric arrays.
distance Parameters
-
numeric array
-
numeric array
distance Syntax
distance(numericArray1, numuericArray2))
div
The div
function will take two numeric values and divide them. The function will fail to execute if any of the values are non-numeric or null, or the 2nd value is 0. Returns a numeric value.
div Parameters
-
Field Name | Raw Number | Number Evaluator
-
Field Name | Raw Number | Number Evaluator
div Syntax
The expressions below show the various ways in which you can use the div
evaluator. The first value will be divided by the second and as such the second cannot be 0.
div(1,2) // 1 / 2
div(1,fieldA) // 1 / fieldA
div(fieldA,1.4) // fieldA / 1.4
div(fieldA,add(fieldA,fieldB)) // fieldA / (fieldA + fieldB)
dotProduct
The dotProduct
function returns the dotproduct of a numeric array.
dotProduct Parameters
-
numeric array
dotProduct Returns
A number.
dotProduct Syntax
dotProduct(numericArray)
earthMoversDistance
The earthMoversDistance
function calculates the Earth Movers distance of two numeric arrays.
earthMoversDistance Parameters
-
numeric array
-
numeric array
earthMoversDistance Returns
A numeric.
earthMoversDistance Syntax
earthMoversDistance(numericArray1, numericArray2))
ebeAdd
The ebeAdd
function performs an element-by-element addition of two numeric arrays.
ebeAdd Parameters
-
numeric array
-
numeric array
ebeAdd Returns
A numeric array.
ebeAdd Syntax
ebeAdd(numericArray, numericArray)
ebeDivide
The ebeDivide
function performs an element-by-element division of two numeric arrays.
ebeDivide Parameters
-
numeric array
-
numeric array
ebeDivide Returns
A numeric array.
ebeDivide Syntax
ebeDivide(numericArray, numericArray)
ebeMultiple
The ebeMultiply
function performs an element-by-element multiplication of two numeric arrays.
ebeMultiply Parameters
-
numeric array
-
numeric array
ebeMultiply Returns
A numeric array.
ebeMultiply Syntax
ebeMultiply(numericArray, numericArray)
ebeSubtract
The ebeSubtract
function performs an element-by-element subtraction of two numeric arrays.
ebeSubtract Parameters
-
numeric array
-
numeric array
ebeSubtract Returns
A numeric array.
ebeSubtract Syntax
ebeSubtract(numericArray, numericArray)
empiricalDistribution
The empiricalDistribution
function returns empirical distribution function, a continuous probability distribution function based
on an actual data set. This function is part of the probability distribution framework and is designed to work with the sample
, kolmogorovSmirnov
and cumulativeProbability
functions.
This function is designed to work with continuous data. To build a distribution from
a discrete data set use the enumeratedDistribution
.
empiricalDistribution Parameters
-
numeric array
: empirical observations
empiricalDistribution Returns
A probability distribution function.
empiricalDistribution Syntax
empiricalDistribution(numericArray)
enumeratedDistribution
The enumeratedDistribution
function returns a discrete probability distribution function based
on an actual data set or a pre-defined set of data and probabilities.
This function is part of the probability distribution framework and is designed to
work with the sample
, probability
and cumulativeProbability
functions.
The enumeratedDistribution can be called in two different scenarios:
1) Single array of discrete values. This works like an empirical distribution for discrete data.
2) An array of singleton discrete values and an array of double values representing the probabilities of the discrete values.
This function is designed to work with discrete data. To build a distribution from
a continuous data set use the empiricalDistribution
.
enumeratedDistribution Parameters
-
integer array
: discrete observations or singleton discrete values. -
double array
: (Optional) values representing the probabilities of the singleton discrete values.
enumeratedDistribution Returns
A probability distribution function.
enumeratedDistribution Syntax
enumeratedDistribution(integerArray) // This creates an enumerated distribution from the observations in the numeric array.
enumeratedDistribution(array(1,2,3,4), array(.25,.25,.25,.25)) // This creates an enumerated distribution with four discrete values (1,2,3,4) each with a probability of .25.
eor
The eor
function will return the logical exclusive or of at least two boolean parameters. The function will fail to execute if any parameters are non-boolean or null. Returns a boolean value.
eor Parameters
-
Field Name | Raw Boolean | Boolean Evaluator
-
Field Name | Raw Boolean | Boolean Evaluator
-
……
-
Field Name | Raw Boolean | Boolean Evaluator
eor Syntax
The expressions below show the various ways in which you can use the eor
evaluator. At least two parameters are required, but there is no limit to how many you can use.
eor(true,fieldA) // true iff fieldA is false
eor(fieldA,fieldB) // true iff either fieldA or fieldB is true but not both
eor(eq(fieldA,fieldB),eq(fieldC,fieldD)) // true iff either fieldA == fieldB or fieldC == fieldD but not both
eq
The eq
function will return whether all the parameters are equal, as per Java’s standard equals(…)
function. The function accepts parameters of any type, but will fail to execute if all the parameters are not of the same type. That is, all are Boolean, all are String, or all are Numeric. If any any parameters are null and there is at least one parameter that is not null then false will be returned. Returns a boolean value.
eq Parameters
-
Field Name | Raw Value | Evaluator
-
Field Name | Raw Value | Evaluator
-
……
-
Field Name | Raw Value | Evaluator
eq Syntax
The expressions below show the various ways in which you can use the eq
evaluator.
eq(1,2) // 1 == 2
eq(1,fieldA) // 1 == fieldA
eq(fieldA,val(foo)) fieldA == "foo"
eq(add(fieldA,fieldB),6) // fieldA + fieldB == 6
expMovingAge
The expMovingAverage
function computes an exponential moving average for a numeric array.
expMovingAge Parameters
-
numeric array
: The array to compute the exponential moving average from. -
integer
: window size
expMovingAvg Returns
A numeric array. The first element of the returned array will start from the windowSize-1 index of the original array.
expMovingAvg Syntax
expMovingAvg(numericArray, 5) //Computes an exponential moving average with a window size of 5.
factorial
The factorial
function returns the factorial of its parameter.
factorial Parameters
-
integer
: The value to compute the factorial for. The largest supported value of this parameter is 170.
factorial Returns
A double.
factorial Syntax
factorial(100) //Computes the factorial of 100
finddelay
The finddelay
function performs a cross-correlation between two numeric arrays and returns the delay.
finddelay Parameters
-
numeric array
-
numeric array
finddelay Syntax
finddelay(numericArray1, numericArray2)
floor
The floor
function rounds a decimal value to the next lowest whole number.
floor Parameters
-
Field Name | Raw Number | Number Evaluator
: The decimal to round down.
floor Syntax
The expressions below show the various ways in which you can use the floor
evaluator.
floor(100.4) // returns 100.
ceil(fieldA) // returns the next lowestt whole number for fieldA.
if(gt(fieldA,fieldB),floor(fieldA),floor(fieldB)) // if fieldA > fieldB then return the floor of fieldA, else return the floor of fieldB.
freqTable
The freqTable
function returns a frequency distribution from
an array of discrete values.
This function is designed to work with discrete values. To work with continuous data
use the hist
function.
freqTable Parameters
-
integer array
: The values to build the frequency distribution from.
freqTable Returns
A list of tuples containing the frequency information for each discrete value.
freqTable Syntax
freqTable(integerArray)
gammaDistribution
The gammaDistribution
function returns a gamma probability distribution based on its parameters. This function is part of the
probability distribution framework and is designed to work with the sample
, kolmogorovSmirnov
and cumulativeProbability
functions.
gammaDistribution Parameters
-
double
: shape -
double
: scale
gammaDistribution Returns
A probability distribution function,
gammaDistribution Syntax
gammaDistribution(1, 10)
gt
The gt
function will return whether the first parameter is greater than the second parameter. The function accepts numeric or string parameters, but will fail to execute if all the parameters are not of the same type. That is, all are String or all are Numeric. If any any parameters are null then an error will be raised. Returns a boolean value.
gt Parameters
-
Field Name | Raw Value | Evaluator
-
Field Name | Raw Value | Evaluator
gt Syntax
The expressions below show the various ways in which you can use the gt
evaluator.
gt(1,2) // 1 > 2
gt(1,fieldA) // 1 > fieldA
gt(fieldA,val(foo)) // fieldA > "foo"
gt(add(fieldA,fieldB),6) // fieldA + fieldB > 6
gteq
The gteq
function will return whether the first parameter is greater than or equal to the second parameter. The function accepts numeric and string parameters, but will fail to execute if all the parameters are not of the same type. That is, all are String or all are Numeric. If any any parameters are null then an error will be raised. Returns a boolean value.
gteq Parameters
-
Field Name | Raw Value | Evaluator
-
Field Name | Raw Value | Evaluator
gteq Syntax
The expressions below show the various ways in which you can use the gteq
evaluator.
gteq(1,2) // 1 >= 2
gteq(1,fieldA) // 1 >= fieldA
gteq(fieldA,val(foo)) fieldA >= "foo"
gteq(add(fieldA,fieldB),6) // fieldA + fieldB >= 6
hist
The hist
function creates a histogram from a numeric array. The hist function is designed
to work with continuous variables.
hist Parameters
-
numeric array
-
bins
: The number of bins in the histogram. Each returned tuple contains summary statistics for the observations that were within the bin.
hist Syntax
hist(numericArray, bins)
hsin
The hsin
function returns the trigonometric hyperbolic sine of a number.
hsin Parameters
-
Field Name | Raw Number | Number Evaluator
: The value to return the hyperbolic sine of.
hsin Syntax
hsin(100.4) // returns the hsine of 100.4
hsin(fieldA) // returns the hsine for fieldA.
if(gt(fieldA,fieldB),sin(fieldA),sin(fieldB)) // if fieldA > fieldB then return the hsine of fieldA, else return the hsine of fieldB
if
The if
function works like a standard conditional if/then statement. If the first parameter is true, then the second parameter will be returned, else the third parameter will be returned. The function accepts a boolean as the first parameter and anything as the second and third parameters. An error will occur if the first parameter is not a boolean or is null.
if Parameters
-
Field Name | Raw Value | Boolean Evaluator
-
Field Name | Raw Value | Evaluator
-
Field Name | Raw Value | Evaluator
if Syntax
The expressions below show the various ways in which you can use the if
evaluator.
if(fieldA,fieldB,fieldC) // if fieldA is true then fieldB else fieldC
if(gt(fieldA,5), fieldA, 5) // if fieldA > 5 then fieldA else 5
if(eq(fieldB,null), null, div(fieldA,fieldB)) // if fieldB is null then null else fieldA / fieldB
kendallsCorr
The kendallsCorr
function returns the Kendall’s Tau-b Rank Correlation of two numeric arrays.
kendallsCorr Parameters
-
numeric array
-
numeric array
kendalsCorr Returns
A double between -1 and 1.
kendalsCorr Syntax
kendallsCorr(numericArray1, numericArray2)
length
The length
function returns the length of a numeric array.
length Parameters
-
numeric array
length Syntax
length(numericArray)
log
The log
function will return the natural log of the provided single parameter. The log
function will fail to execute if the value is non-numeric. If a null value is found, then null will be returned as the result.
log Parameters
-
Field Name | Raw Number | Number Evaluator
log Syntax
The expressions below show the various ways in which you can use the log
evaluator. Only one parameter is accepted. Returns a numeric value.
log(100)
log(add(fieldA,fieldB))
log(fieldA)
logNormalDistribution
The logNormalDistribution
function returns a log normal probability distribution based on its parameters. This function is part of the probability distribution framework and is designed to
work with the sample
, kolmogorovSmirnov
and cumulativeProbability
functions.
logNormalDistribution Parameters
-
double
: shape -
double
: scale
logNormalDistribution Returns
A probability distribution function.
logNormalDistribution Syntax
logNormalDistribution(.3, .0)
kolmogorovSmirnov
The kolmogorovSmirnov
function performs a Kolmogorov Smirnov test,
between a reference continuous probability distribution and a sample set.
The supported distribution functions are: empiricalDistribution
, normalDistribution
, logNormalDistribution
, weibullDistribution
, gammaDistribution
, and betaDistribution
.
kolmogorovSmirnov Parameters
-
continuous probability distribution
: Reference distribution -
numeric array
: sample set
kolmogorovSmirnov Returns
result tuple : A tuple containing the p-value and d-statistic for the test result.
kolmogorovSmirnov Syntax
kolmogorovSmirnov(normalDistribution(10, 2), sampleSet)
lt
The lt
function will return whether the first parameter is less than the second parameter. The function accepts numeric or string parameters, but will fail to execute if all the parameters are not of the same type. That is, all are String or all are Numeric. If any any parameters are null then an error will be raised. Returns a boolean value.
lt Parameters
-
Field Name | Raw Value | Evaluator
-
Field Name | Raw Value | Evaluator
lt Syntax
The expressions below show the various ways in which you can use the lt
evaluator.
lt(1,2) // 1 < 2
lt(1,fieldA) // 1 < fieldA
lt(fieldA,val(foo)) fieldA < "foo"
lt(add(fieldA,fieldB),6) // fieldA + fieldB < 6
lteq
The lteq
function will return whether the first parameter is less than or equal to the second parameter. The function accepts numeric and string parameters, but will fail to execute if all the parameters are not of the same type. That is, all are String or all are Numeric. If any any parameters are null then an error will be raised. Returns a boolean value.
lteq Parameters
-
Field Name | Raw Value | Evaluator
-
Field Name | Raw Value | Evaluator
lteq Syntax
The expressions below show the various ways in which you can use the lteq
evaluator.
lteq(1,2) // 1 <= 2
lteq(1,fieldA) // 1 <= fieldA
lteq(fieldA,val(foo)) fieldA <= "foo"
lteq(add(fieldA,fieldB),6) // fieldA + fieldB <= 6
manhattanDistance
The manhattanDistance
function calculates the Manhattan distance of two numeric arrays.
manhattanDistance Parameters
-
numeric array
-
numeric array
manhattanDistance Returns
A numeric.
manhattanDistance Syntax
manhattanDistance(numericArray1, numuericArray2))
meanDifference
The meanDifference
function calculates the mean of the differences following the element-by-element subtraction between two numeric arrays.
meanDifference Parameters
-
numeric array
-
numeric array
meanDifference Returns
A numeric.
meanDifference Syntax
meanDifference(numericArray, numericArray)
mod
The mod
function returns the remainder (modulo) of the first parameter divided by the second parameter.
mod Parameters
-
Field Name | Raw Number | Number Evaluator
: Parameter 1 -
Field Name | Raw Number | Number Evaluator
: Parameter 2
mod Syntax
The expressions below show the various ways in which you can use the mod
evaluator.
mod(100,3) // returns the remainder of 100 / 3 .
mod(100,fieldA) // returns the remainder of 100 divided by the value of fieldA.
mod(fieldA,1.4) // returns the remainder of fieldA divided by 1.4.
if(gt(fieldA,fieldB),mod(fieldA,fieldB),mod(fieldB,fieldA)) // if fieldA > fieldB then return the remainder of fieldA/fieldB, else return the remainder of fieldB/fieldA.
monteCarlo
The monteCarlo
function performs a Monte Carlo simulation (https://en.wikipedia.org/wiki/Monte_Carlo_method)
based on its parameters. The monteCarlo function runs another function a specified number of times and returns the results.
The function being run typically has one or more variables that are drawn from probability
distributions on each run. The sample
function is used in the function to draw the samples.
The simulation’s result array can then be treated as an empirical distribution to understand the probabilities of the simulation results.
monteCarlo Parameters
-
numeric function
: The function being run by the simulation, which must return a numeric value. -
integer
: The number of times to run the function.
monteCarlo Returns
A numeric array: The results of simulation runs.
monteCarlo Syntax
let(a=uniformIntegerDistribution(1, 6),
b=uniformIntegerDistribution(1, 6),
c=monteCarlo(add(sample(a), sample(b)), 1000))
In the expression above the monteCarlo
function is running the function add(sample(a), sample(b))
1000 times and returning the result. Each time the function is run samples are drawn from the
probability distributions stored in variables a
and b
.
movingAvg
The movingAvg
function calculates a moving average over an array of numbers.
movingAvg Parameters
-
numeric array
-
window size
movingAvg Returns
A numeric array. The first element of the returned array will start from the windowSize-1 index of the original array.
movingAvg Syntax
movingAverage(numericArray, 30)
movingMedian
The movingMedian
function calculates a moving median over an array of numbers.
movingMedian Parameters
-
numeric array
-
window size
movingMedian Returns
A numeric array. The first element of the returned array will start from the windowSize-1 index of the original array.
movingMedian Syntax
movingMedian(numericArray, 30)
mult
The mult
function will take two or more numeric values and multiply them together. The mult
function will fail to execute if any of the values are non-numeric. If a null value is found then null will be returned as the result.
mult Parameters
-
Field Name | Raw Number | Number Evaluator
-
Field Name | Raw Number | Number Evaluator
-
……
-
Field Name | Raw Number | Number Evaluator
mult Syntax
The expressions below show the various ways in which you can use the mult
evaluator. The number and order of these parameters do not matter and is not limited except that at least two parameters are required. Returns a numeric value.
mult(1,2,3,4) // 1 * 2 * 3 * 4
mult(1,fieldA) // 1 * value of fieldA
mult(fieldA,1.4) // value of fieldA * 1.4
mult(fieldA,fieldB,fieldC) // value of fieldA * value of fieldB * value of fieldC
mult(fieldA,div(fieldA,fieldB)) // value of fieldA * (value of fieldA / value of fieldB)
mult(fieldA,if(gt(fieldA,fieldB),fieldA,fieldB)) // if fieldA > fieldB then fieldA * fieldA, else fieldA * fieldB
normalDistribution
The normalDistribution
function returns a normal probability distribution
based on its parameters. This function is part of the probability distribution framework and is designed to
work with the sample
, kolmogorovSmirnov
and cumulativeProbability
functions.
normalDistribution Parameters
-
double
: mean -
double
: standard deviation
normalDistribution Returns
A probability distribution function.
normalDistribution Syntax
normalDistribution(mean, stddev)
normalize
The normalize
function normalizes a numeric array so that values within the array
have a mean of 0 and standard deviation of 1.
normalize Parameters
-
numeric array
normalize Syntax
normalize(numericArray)
not
The not
function will return the logical NOT of a single boolean parameter. The function will fail to execute if the parameter is non-boolean or null. Returns a boolean value.
not Parameters
-
Field Name | Raw Boolean | Boolean Evaluator
not Syntax
The expressions below show the various ways in which you can use the not
evaluator. Only one parameter is allowed.
not(true) // false
not(fieldA) // true if fieldA is false else false
not(eq(fieldA,fieldB)) // true if fieldA != fieldB
or
The or
function will return the logical OR of at least 2 boolean parameters. The function will fail to execute if any parameters are non-boolean or null. Returns a boolean value.
or Parameters
-
Field Name | Raw Boolean | Boolean Evaluator
-
Field Name | Raw Boolean | Boolean Evaluator
-
……
-
Field Name | Raw Boolean | Boolean Evaluator
or Syntax
The expressions below show the various ways in which you can use the or
evaluator. At least two parameters are required, but there is no limit to how many you can use.
or(true,fieldA) // true || fieldA
or(fieldA,fieldB) // fieldA || fieldB
or(and(fieldA,fieldB),fieldC) // (fieldA && fieldB) || fieldC
or(fieldA,fieldB,fieldC,and(fieldD,fieldE),fieldF)
poissonDistribution
The poissonDistribution
function returns a poisson probability distribution
based on its parameter. This function is part of the probability distribution framework and is designed to
work with the sample
, probability
and cumulativeProbability
functions.
poissonDistribution Parameters
-
double
: mean
poissonDistribution Returns
A probability distribution function.
poissonDistribution Syntax
poissonDistribution(mean)
polyFit
The polyFit
function performs polynomial curve fitting.
polyFit Parameters
-
numeric array
: (Optional) x values. If omitted a sequence will be created for the x values. -
numeric array
: y values -
integer
: (Optional) polynomial degree. Defaults to 3.
polyFit Returns
A numeric array: curve that was fit to the data points.
polyFit Syntax
polyFit(yValues) // This creates the xValues automatically and fits a curve through the data points using the default 3 degree polynomial.
polyFit(yValues, 5) // This creates the xValues automatically and fits a curve through the data points using a 5 degree polynomial.
polyFit(xValues, yValues, 5) // This will fit a curve through the data points using a 5 degree polynomial.
polyfitDerivative
The polyfitDerivative
function returns the derivative of the curve created by the polynomial curve fitter.
polyfitDerivative Parameters
-
numeric array
: (Optional) x values. If omitted a sequence will be created for the x values. -
numeric array
: y values -
integer
: (Optional) polynomial degree. Defaults to 3.
polyfitDerivative Returns
A numeric array: The curve for the derivative created by the polynomial curve fitter.
polyfitDerivative Syntax
polyfitDerivative(yValues) // This creates the xValues automatically and returns the polyfit derivative
polyfitDerivative(yValues, 5) // This creates the xValues automatically and fits a curve through the data points using a 5 degree polynomial and returns the polyfit derivative.
polyfitDerivative(xValues, yValues, 5) // This will fit a curve through the data points using a 5 degree polynomial and returns the polyfit derivative.
pow
The pow
function returns the value of its first parameter raised to the power of its second parameter.
pow Parameters
-
Field Name | Raw Number | Number Evaluator
: Parameter 1 -
Field Name | Raw Number | Number Evaluator
: Parameter 2
pow Syntax
The expressions below show the various ways in which you can use the pow
evaluator.
pow(2,3) // returns 2 raised to the 3rd power.
pow(4,fieldA) // returns 4 raised by the value of fieldA.
pow(fieldA,1.4) // returns the value of fieldA raised by 1.4.
if(gt(fieldA,fieldB),pow(fieldA,fieldB),pow(fieldB,fieldA)) // if fieldA > fieldB then raise fieldA by fieldB, else raise fieldB by fieldA.
predict
The predict
function predicts the value of an dependent variable based on
the output of the regress function.
predict Parameters
-
regress output
-
numeric predictor
predict Syntax
predict(regressOutput, predictor)
primes
The primes
function returns an array of prime numbers starting from a specified number.
primes Parameters
-
integer
: The number of primes to return in the list -
integer
: The starting point for returning the primes
primes Returns
A numeric array.
primes Syntax
primes(100, 2000) // returns 100 primes starting from 2000
probability
The probability
function returns the probability of a random variable within a discrete probability distribution.
probability Parameters
-
discrete probability distribution
: poissonDistribution | binomialDistribution | uniformDistribution | enumeratedDistribution -
integer
: Value of the random variable to compute the probability for.
probability Returns
A double: the probability.
probability Syntax
probability(poissonDistribution(10), 7) // Returns the probability of a random sample of 7 in a poisson distribution with a mean of 10.
rank
The rank
performs a rank transformation on a numeric array.
rank Parameters
-
numeric array
rank Syntax
rank(numericArray)
raw
The raw
function will return whatever raw value is the parameter. This is useful for cases where you want to use a string as part of another evaluator.
raw Parameters
-
Raw Value
raw Syntax
The expressions below show the various ways in which you can use the raw
evaluator. Whatever is inside will be returned as-is. Internal evaluators are considered strings and are not evaluated.
raw(foo) // "foo"
raw(count(*)) // "count(*)"
raw(45) // 45
raw(true) // "true" (note: this returns the string "true" and not the boolean true)
eq(raw(fieldA), fieldA) // true if the value of fieldA equals the string "fieldA"
regress
residuals
The residuals
function takes three parameters: a simple regression model, an array of predictor values
and an array of actual values. The residuals function applies the simple regression model to the
array of predictor values and computes a predictions array. The predicted values array is then
subtracted from the actual value array to compute the residuals array.
residuals Parameters
-
regress output
-
numeric array
: The array of predictor values -
numeric array
: The array of actual values
residuals Returns
A numeric array of residuals.
residuals Syntax
residuals(regressOutput, numericArray, numericArray)
rev
The rev
function reverses the order of a numeric array.
rev Parameters
-
numeric array
rev Syntax
rev(numericArray)
round
The round
function returns the closest whole number to the argument.
round Parameters
-
Field Name | Raw Number | Number Evaluator
: The value to return the square root of.
round Syntax
round(100.4)
round(fieldA)
if(gt(fieldA,fieldB),sqrt(fieldA),sqrt(fieldB)) // if fieldA > fieldB then return the round of fieldA, else return the round of fieldB
sample
The sample
function can be used to draw random samples from a probability distribution.
sample Parameters
-
probability distribution
: The distribution to sample. -
integer
: (Optional) Sample size. Defaults to 1.
sample Returns
Either a single numeric random sample, or a numeric array depending on the sample size parameter.
sample Syntax
sample(poissonDistribution(5)) // Returns a single random sample from a poissonDistribution with mean of 5.
sample(poissonDistribution(5), 1000) // Returns 1000 random samples from poissonDistribution with a mean of 5.
scale
The scale
function multiplies all the elements of an array by a number.
scale Parameters
-
number
-
numeric array
scale Syntax
scale(number, numericArray)
sequence
The sequence
function returns an array of numbers based on its parameters.
sequence Parameters
-
length
-
start
-
stride
sequence Syntax
sequence(100, 0, 1) // Returns a sequence of length 100, starting from 0 with a stride of 1.
sin
The sin
function returns the trigonometric sine of a number.
sin Parameters
-
Field Name | Raw Number | Number Evaluator
: The value to return the sine of.
sin Syntax
sin(100.4) // returns the sine of 100.4
sine(fieldA) // returns the sine for fieldA.
if(gt(fieldA,fieldB),sin(fieldA),sin(fieldB)) // if fieldA > fieldB then return the sine of fieldA, else return the sine of fieldB
spearmansCorr
The spearmansCorr
function returns the Spearmans Rank Correlation of two numeric arrays.
spearmansCorr Parameters
-
numeric array
-
numeric array
spearmansCorr Returns
A double between -1 and 1.
spearmansCorr Syntax
spearmansCorr(numericArray1, numericArray2)
sqrt
The sqrt
function returns the trigonometric square root of a number.
sqrt Parameters
-
Field Name | Raw Number | Number Evaluator
: The value to return the square root of.
sqrt Syntax
sqrt(100.4) // returns the square root of 100.4
sqrt(fieldA) // returns the square root for fieldA.
if(gt(fieldA,fieldB),sqrt(fieldA),sqrt(fieldB)) // if fieldA > fieldB then return the sqrt of fieldA, else return the sqrt of fieldB
sub
The sub
function will take 2 or more numeric values and subtract them, from left to right. The sub
function will fail to execute if any of the values are non-numeric. If a null value is found then null
will be returned as the result.
sub Parameters
-
Field Name | Raw Number | Number Evaluator
-
Field Name | Raw Number | Number Evaluator
-
……
-
Field Name | Raw Number | Number Evaluator
sub Syntax
The expressions below show the various ways in which you can use the sub
evaluator. The number of these parameters does not matter and is not limited except that at least two parameters are required. Returns a numeric value.
sub(1,2,3,4) // 1 - 2 - 3 - 4
sub(1,fieldA) // 1 - value of fieldA
sub(fieldA,1.4) // value of fieldA - 1.4
sub(fieldA,fieldB,fieldC) // value of fieldA - value of fieldB - value of fieldC
sub(fieldA,div(fieldA,fieldB)) // value of fieldA - (value of fieldA / value of fieldB)
if(gt(fieldA,fieldB),sub(fieldA,fieldB),sub(fieldB,fieldA)) // if fieldA > fieldB then fieldA - fieldB, else fieldB - field
sumDifference
The sumDifference
function calculates the sum of the differences following an element-by-element subtraction between two numeric arrays.
sumDifference Parameters
-
numeric array
-
numeric array
sumDifference Returns
A numeric.
sumDifference Syntax
sumDifference(numericArray, numericArray)
uniformDistribution
The uniformDistribution
function returns a continuous uniform probability distribution
based on its parameters. See the uniformIntegerDistribution
to work with discrete uniform distributions. This function is part of the
probability distribution framework and is designed to work with the sample
and cumulativeProbability
functions.
uniforDistribution Parameters
-
double
: start -
double
: end
uniformDistribution Returns
A probability distribution function.
uniformDistribution Syntax
uniformDistribution(0.0, 100.0)
uniformIntegerDistribution
The uniformIntegerDistribution
function returns a discrete uniform probability distribution
based on its parameters. See the uniformDistribution
to work with continuous uniform distributions. This function is part of the
probability distribution framework and is designed to work with the sample
, probability
and cumulativeProbability
functions.
uniformIntegerDistribution Parameters
-
integer
: start -
integer
: end
uniformIntegerDistribution Returns
A probability distribution function.
uniformIntegerDistribution Syntax
uniformDistribution(1, 6)
weibullDistribution
The weibullDistribution
function returns a Weibull probability distribution
based on its parameters. This function is part of the
probability distribution framework and is designed to work with the sample
, kolmogorovSmirnov
and cumulativeProbability
functions.
weibullDistribution Parameters
-
double
: shape -
double
: scale
weibullDistribution Returns
A probability distribution function.
weibullDistribution Syntax
weibullDistribution(.5, 10)
zipFDistribution
The zipFDistribution
function returns a ZipF distribution
based on its parameters. This function is part of the
probability distribution framework and is designed to work with the sample
,
probability
and cumulativeProbability
functions.
zipFDistribution Parameters
-
integer
: size -
double
: exponent
zipFDistribution Returns
A probability distribution function.
zipFDistribution Syntax
zipFDistribution(5000, 1.0)
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