SLA_XY2XY - Apply Linear Model to an

**ACTION:**- Transform one into another using a linear model of the type
produced by the sla_FITXY routine.
**CALL:**`CALL sla_XY2XY (X1,Y1,COEFFS,X2,Y2)`

**GIVEN:**-

*X1,Y1***D**before transformation *COEFFS***D(6)**transformation coefficients (see note)

**RETURNED:**-

*X2,Y2***D**after transformation

**NOTES:**- 1.
- The model relates two sets of coordinates as follows.
Naming the six elements of COEFFS
*a*,*b*,*c*,*d*,*e*&*f*, the present routine performs the transformation:*x*=_{2}*a*+*bx*+_{1}*cy*_{1}

*y*=_{2}*d*+*ex*+_{1}*fy*_{1} - 2.
- See also sla_FITXY, sla_PXY, sla_INVF, sla_DCMPF.

Starlink User Note 67

P. T. Wallace

12 October 1999

E-mail:ptw@star.rl.ac.uk