SigmaXX Command
From GeoGebra Manual
- SigmaXX( <List of Points> )
- Calculates the sum of squares of the x-coordinates of the given points.
- Example: Let
list1 = {(-3, 4), (-1, 4), (-2, 3), (1, 3), (2, 2), (1, 5)}
be a list of points.SigmaXX(list1)
yields the value 20.
- SigmaXX( <List of Raw Data> )
- Calculates the sum of squares of the given numbers.
- Example: In order to work out the variance of a list you may use
SigmaXX(list) / Length(list) - Mean(list)^2
.
- SigmaXX( <List of Numbers>, <List of Frequencies> )
- Calculates the weighted sum of squares of the given numbers.
- Example: Let
list1 = {3, 2, 4, 3, 3, 2, 1, 1, 2, 3, 3, 4, 5, 3, 2, 1, 1, 2, 3}
be a list of numbers.Unique(list1)
yields list2 = {1, 2, 3, 4, 5} andFrequency(list1)
yields list3 = {4, 5, 7, 2, 1}. CommandSigmaXX(list2, list3)
yields the value 144.