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Aggregate Functions
Average
Takes an average value of the arguments
average(arg)
mean(arg)
Examples
average(${val})
${val} = [10, 20, 30, 40]
> 25
mean(${val})
${val} = [10, 20, 30, 40]
> 25
Count
Counts the number of records that are passed through it. Doesn’t take any notice of the values of any fields.
count()
Examples
Supplying 3 values...
count()
> 3
Count Groups
This is used to count the number of unique values where there are multiple group levels. For Example, a data set grouped as follows
- Group by Name
- Group by Type
A groupCount could be used to count the number of distinct values of ’type’ for each value of ’name'
Count Unique
This is used to count the number of unique values passed to the function where grouping is used to aggregate values in other columns. For Example, a data set grouped as follows
- Group by Name
- Group by Type
countUnique() could be used to count the number of distinct values of ’type’ for each value of ’name'
Examples
countUnique(${val})
${val} = ['bill', 'bob', 'fred', 'bill']
> 3
Joining
Concatenates all values together into a single string. If a delimter is supplied then the delimiter is placed bewteen each concatenated string. If a limit is supplied then it will only concatenate up to limit values.
joining(values)
joining(values, delimiter)
joining(values, delimiter, limit)
Examples
joining(${val}, ', ')
${val} = ['bill', 'bob', 'fred', 'bill']
> 'bill, bob, fred, bill'
Max
Determines the maximum value given in the args
max(arg)
Examples
max(${val})
${val} = [100, 30, 45, 109]
> 109
# They can be nested
max(max(${val}), 40, 67, 89)
${val} = [20, 1002]
> 1002
Min
Determines the minimum value given in the args
min(arg)
Examples
min(${val})
${val} = [100, 30, 45, 109]
> 30
They can be nested
min(max(${val}), 40, 67, 89)
${val} = [20, 1002]
> 20
Standard Deviation
Calculate the standard deviation for a set of input values.
stDev(arg)
Examples
round(stDev(${val}))
${val} = [600, 470, 170, 430, 300]
> 147
Sum
Sums all the arguments together
sum(arg)
Examples
sum(${val})
${val} = [89, 12, 3, 45]
> 149
Variance
Calculate the variance of a set of input values.
variance(arg)
Examples
variance(${val})
${val} = [600, 470, 170, 430, 300]
> 21704