Functions Reference

24 FileMaker Functions Reference
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 the sample 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 1::field A,
table 2::field B,...). You can name a different table for each field (table
1::field A;table 2::field B...).
Examples
A portal displays the related values 5, 6, 7, and 8 in a field called Scores.
StDev(table::Scores) returns 1.29099444....
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.
StDev(Field4) results in an error because standard deviation of a single number is not
defined.
StDev(Field1;Field2;Field3) returns 2.64575131..., 3.05505046...,
2.12132034..., 2.82842712... for a repeating field.
Note When a referenced field is a repeating field, the StDev function returns the standard
deviation in the first repetition fields, then the standard deviation in the second repetition
fields, and so on.
StDev
x
1
2
x
2
2
… x
n
2
+++
n1–
------------------------------------------
x
1
x
2
… x
n
+++()
2
nn 1–()
-------------------------------------------------–=