Initialize Sine Odd-Wave Transform

Calling Sequence

CALL SINTI	(N, RWSAVE)
CALL DSINTI	(N, DWSAVE)
CALL VSINTI	(N, WSAVE)
CALL VDSINTI	(N, WSAVE)
void sinti	(int n, float *rwsave)
void dsinti	(int n, double *dwsave)
void vsinti	(int n, float *rwsave)
void vdsinti	(int n, double *dwsave)

Arguments

N	Length of the sequence to be transformed. N 0.
xWSAVE	On entry, an array with a dimension of at least (3 × N + 15). Different xWSAVE arrays are required for different values of N. This initialization does not have to be repeated between calls to xSINT as long as N and xWSAVE remain unchanged, thus subsequent transforms can be obtained faster than the first.

Sample Program

PROGRAM TEST

IMPLICIT NONE

C

INTEGER N

PARAMETER (N = 9)

C

INTEGER I

REAL PI, WSAVE(3 * N + 15), X(N)

C

EXTERNAL SINT, SINTI

INTRINSIC ACOS, SIN

C

C Initialize the array X to an odd sequence, that is, it

C can be expanded in terms of a trigonometric series that

C contains only sine terms.

C

PI = ACOS (-1.0)

DO 100, I=1, N

X(I) = SIN ( I * 2.0 * PI / (N + 1.0))

100 CONTINUE

C

PRINT 1000

PRINT 1010, (X(I), I = 1, N)

CALL SINTI (N, WSAVE)

CALL SINT (N, X, WSAVE)

PRINT 1020

PRINT 1010, (X(I), I = 1, N)

CALL SINT (N, X, WSAVE)

PRINT 1030

PRINT 1010, (X(I), I = 1, N)

C

1000 FORMAT (1X, 'Original Sequence: ')

1010 FORMAT (1X, 100(F7.3, 1X))

1020 FORMAT (1X, 'Transformed Sequence: ')

1030 FORMAT (1X, 'Recovered Sequence: ')

C

END

Sample Output

Original Sequence:
0.588 0.951 0.951 0.588 0.000 -0.588 -0.951 -0.951 -0.588
Transformed Sequence:
0.000 10.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
Recovered Sequence:
11.756 19.021 19.021 11.756 0.000 -11.756 -19.021 -19.021 -11.756