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Aggregate Functions
Aggregate functions require that the dashboard columns without aggregate functions have a grouping level applied. The aggregate function will then be evaluated against the values in the group.
Average
Takes an average value of the arguments
average(arg)
mean(arg)
Examples
average(${val})
${val} = [10, 20, 30, 40]
> 25
mean(${val})
${val} = [10, 20, 30, 40]
> 25
Count
Counts the number of records that are passed through it. Doesn’t take any notice of the values of any fields.
count()
Example
Supplying 3 values...
count()
> 3
Count Groups
This is used to count the number of unique values where there are multiple group levels. For Example, a data set grouped as follows
- Group by Name
- Group by Type
A groupCount could be used to count the number of distinct values of ’type’ for each value of ’name'
Count Unique
This is used to count the number of unique values passed to the function where grouping is used to aggregate values in other columns. For Example, a data set grouped as follows
- Group by Name
- Group by Type
countUnique()
could be used to count the number of distinct values of ’type’ for each value of ’name'
Example
countUnique(${val})
${val} = ['bill', 'bob', 'fred', 'bill']
> 3
Distinct
Concatenates all distinct (unique) values together into a single string.
Works in the same way as joining()
except that it discards duplicate values.
Values are concatenated in the order that they are given to the function.
If a delimiter is supplied then the delimiter is placed between each concatenated string.
If a limit is supplied then it will only concatenate up to limit values.
distinct(values)
distinct(values, delimiter)
distinct(values, delimiter, limit)
Examples
distinct(${val}, ', ')
${val} = ['bill', 'bill', 'bob', 'fred', 'bill']
> 'bill, bob, fred'
distinct(${val}, '|', 2)
${val} = ['bill', 'bill', 'bob', 'fred', 'bill']
> 'bill|bob'
See Also
Selection Functions that work in a similar way to distinct()
.
Joining
Concatenates all values together into a single string.
Works in the same way as distinct()
except that duplicate values are included.
Values are concatenated in the order that they are given to the function.
If a delimiter is supplied then the delimiter is placed between each concatenated string.
If a limit is supplied then it will only concatenate up to limit values.
joining(values)
joining(values, delimiter)
joining(values, delimiter, limit)
Example
joining(${val}, ', ')
${val} = ['bill', 'bob', 'fred', 'bill']
> 'bill, bob, fred, bill'
See Also
Selection Functions that work in a similar way to joining()
.
Max
Determines the maximum value given in the args.
max(arg)
Examples
max(${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