stDevP()
returns the standard deviation for the given value over a group. It uses a standard two-pass method, with N as the denominator, and should be used when calculating the standard deviation for an entire population. When the standard variation of only a sample of the population is being calculated, stDev should be used.
Syntax: stDevP(expression)
Returns: A Float
Arguments
Name | Description |
expression | A numeric expression. |
Example
MATCH (n:Person)
RETURN stDevP(n.age)
The population standard deviation of the values in the property age for all nodes of the type ‘Person’ is returned.
Considerations
- All null values are excluded from the calculation.
stDevP(null)
returns0
.
Example
UNWIND [8, 9, 10, 11, 12, 15] AS val
RETURN stDevP(val)
Returns the following Result
stDevP(val) |
2.266911751455907 |