Apple Numbers '08 - Manual (Page 217)

Chapter 12 Dictionary of Functions 217
CORREL
The CORREL function calculates the correlation between two data sets based on linear
regression analysis.
CORREL(y-range, x-range)
 y-range: A range of cells containing the dependent variable (y).
 x-range: A range of cells containing the independent variable (x).
COS
The COS function calculates the cosine of an angle expressed in radians.
COS(radian-angle)
 radian-angle: A number representing an angle in radians.
Notes
To work with angles in radians, use the RADIANS function to convert the degrees to
radians. See the second example below.
To express radians as a multiple of pi, use the PI function. See the third and fourth
examples below.
Examples
Given the following table:
CORREL(D2:D7, E2:E7) returns 1.
CORREL(B2:B7, A2:A7) returns 0.977265.
Examples
COS(1) returns 0.540302306, the cosine of 1 radian (approximately 57.3 degrees).
COS(RADIANS(60)) returns 0.5, the cosine of 60 degrees.
COS(PI()/3) returns 0.5, pi/3 radians (60 degrees).
COS(PI()) returns -1, the cosine of pi radians (180 degrees).