17 lines
990 B
Fortran
17 lines
990 B
Fortran
SUBROUTINE LAGRAN(X0,X1,X2,Y0,Y1,Y2,X,Y)
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C =========================================
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C
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C ***
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C *** Lagrange interpolation for three points
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C ***
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INCLUDE 'IMPLIC.FOR'
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C
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XL0=(X-X1)*(X-X2)/(X0-X1)/(X0-X2)
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XL1=(X-X0)*(X-X2)/(X1-X0)/(X1-X2)
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XL2=(X-X0)*(X-X1)/(X2-X0)/(X2-X1)
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Y=Y0*XL0+Y1*XL1+Y2*XL2
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RETURN
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END
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