Functions Reference

Chapter 2
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Aggregate functions 25
StDevP
Format
StDevP(field{;field... })
Parameter
field - any related field, repeating field, or set of non-repeating fields; or an expression
that returns a field, repeating field, or set of non-repeating fields.
Parameters in curly braces { } are optional.
Data type returned
number
Description
Returns the standard deviation of a population represented by a series of non-blank
values in:
• a repeating field (repeatingField).
• a field in matching related records specified by (table::field), whether or not
these records appear in a portal.
• several non-repeating fields in a record (field1;field2;field3...).
• corresponding repetitions of repeating fields in a record
(repeatingField1;repeatingField2;repeatingField3), if the result is
returned in a repeating field with at least the same number of repeats.
• several fields in the first matching record specified by
(table::field1;table::field2;...). You can include fields from different
tables (table 1::field A;table 2::field B...).
Examples
A portal displays the related values 5, 6, 7, and 8 in the field Scores.
StDevP(table::Scores) returns 1.11803398....
In the following examples:
• Field1 contains two repetitions with values of 1 and 2.
• Field2 contains four repetitions with values of 5, 6, 7, and 8.
• Field3 contains four repetitions with values of 6, 0, 4, and 4.
• Field4 contains one repetition with a value of 3.
StDevP(Field4) results in an error because the population standard deviation of a
single number is not defined.
StDevP
x
1
2
x
2
2
… x
n
2
+++
n
------------------------------------------
x
1
x
2
… x
n
+++
n
-----------------------------------------
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