SUB mathlinfit (n%, x!(), y!(), m!, b!)

'****************************************************************************
'This subroutine does a least squares linear fit to the (x,y) data points.
'It returns the slope and intercept of the line.
'
'Input:
' n%, the number of (x,y) points
' x!(1 to n%), the x values
' y!(1 to n%), the y values
'
'Output:
' m!, the fitted line's slope
' b!, the fitted line's intercept
'
'Zachary Wolf
'5/12/94
'****************************************************************************

'Compute various sums
Sxy! = 0!
Sxx! = 0!
Sx! = 0!
Sy! = 0!
FOR i% = 1 TO n%
 Sxy! = Sxy! + x!(i%) * y!(i%)
 Sxx! = Sxx! + x!(i%) * x!(i%)
 Sx! = Sx! + x!(i%)
 Sy! = Sy! + y!(i%)
NEXT i%

'Compute the determinant
D! = n% * Sxx! - Sx! * Sx!

'Compute the slope and intercept
m! = (Sxy! * n% - Sx! * Sy!) / D!
b! = (Sxx! * Sy! - Sxy! * Sx!) / D!

END SUB