slaXy2xy -

SYNOPSYS

PARAMETERS

double xc1

double yc1

double *coeffs

double *xc2

double *yc2

DESCRIPTION

  Transform one [x,y] into another using a linear model of the type
  produced by the slaFitxy routine.

Given

     xc1      double        x-coordinate
     yc1      double        y-coordinate

Returned

     coeffs   double[6]     transformation coefficients (see note)
     *xc2     double        x-coordinate
     *yc2     double        y-coordinate

  The model relates two sets of [x,y] coordinates as follows.

Naming the elements of coeffs

     coeffs[0] = a
     coeffs[1] = b
     coeffs[2] = c
     coeffs[3] = d
     coeffs[4] = e
     coeffs[5] = f

the present routine performs the transformation

     xc2 = a + b*xc1 + c*yc1
     yc2 = d + e*xc1 + f*yc1

  See also slaFitxy, slaPxy, slaInvf, slaDcmpf.

  P.T.Wallace   Starlink   22 December 1993

SEE ALSO

• slalib.3