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*DECK DETPAR
SUBROUTINE DETPAR(X1,X2,X3,Y1,Y2,Y3,AS,BS,CS)
*
*----------------------------------------------------------------------
*Purpose:
* Routine calculating the parabolic coefficients needed for
* a parabolic interpolation Y = AS*X*X + BS*X + CS
*
*Author(s):
* M. Beaudet
*
*Parameters:
* X1
* X2
* X3
* Y1
* Y2
* Y3
* AS
* BS
* CS
*
*----------------------------------------------------------------------
*
ANUM = Y1*(X2-X3)+Y3*(X1-X2)+Y2*(X3-X1)
ADEN = (X1-X2)*(X1-X3)*(X2-X3)
AS = ANUM/ADEN
BS = (Y2-Y3-AS*(X2*X2-X3*X3))/(X2-X3)
CS = Y1-BS*X1-AS*X1*X1
RETURN
END
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