C CNP 10
C ..................................................................CNP 20
C CNP 30
C SUBROUTINE CNP CNP 40
C CNP 50
C PURPOSE CNP 60
C COMPUTE THE VALUES OF THE CHEBYSHEV POLYNOMIALS T(N,X) CNP 70
C FOR ARGUMENT VALUE X AND ORDERS 0 UP TO N. CNP 80
C CNP 90
C USAGE CNP 100
C CALL CNP(Y,X,N) CNP 110
C CNP 120
C DESCRIPTION OF PARAMETERS CNP 130
C Y - RESULT VECTOR OF DIMENSION N+1 CONTAINING THE VALUESCNP 140
C OF CHEBYSHEV POLYNOMIALS OF ORDER 0 UP TO N CNP 150
C FOR GIVEN ARGUMENT X. CNP 160
C Y - RESULT VALUE CNP 170
C VALUES ARE ORDERED FROM LOW TO HIGH ORDER CNP 180
C X - ARGUMENT OF CHEBYSHEV POLYNOMIAL CNP 190
C N - ORDER OF CHEBYSHEV POLYNOMIAL CNP 200
C CNP 210
C REMARKS CNP 220
C N LESS THAN 0 IS TREATED AS IF N WERE 0 CNP 230
C CNP 240
C SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED CNP 250
C NONE CNP 260
C CNP 270
C METHOD CNP 280
C EVALUATION IS BASED ON THE RECURRENCE EQUATION FOR CNP 290
C CHEBYSHEV POLYNOMIALS T(N,X) CNP 300
C T(N+1,X)=2*X*T(N,X)-T(N-1,X), CNP 310
C WHERE THE FIRST TERM IN BRACKETS IS THE ORDER, CNP 320
C THE SECOND IS THE ARGUMENT. CNP 330
C STARTING VALUES ARE T(0,X)=1, T(1,X)=X. CNP 340
C CNP 350
C ..................................................................CNP 360
C CNP 370
SUBROUTINE CNP(Y,X,N) CNP 380
C CNP 390
DIMENSION Y(1) CNP 400
Y(1)=1. CNP 410
IF(N)1,1,2 CNP 420
1 RETURN CNP 430
C CNP 440
2 Y(2)=X CNP 450
IF(N-1)1,1,3 CNP 460
C CNP 470
C INITIALIZATION CNP 480
3 F=X+X CNP 490
C CNP 500
DO 4 I=2,N CNP 510
4 Y(I+1)=F*Y(I)-Y(I-1) CNP 520
RETURN CNP 530
END CNP 540