HRRRR

Computes the Hadamard product of two real rectangular matrices.

Required Arguments

A — Real NRA by NCA rectangular matrix. (Input)

B — Real NRB by NCB rectangular matrix. (Input)

C — Real NRC by NCC rectangular matrix containing the Hadamard product of A and B. (Output)
If A is not needed, then C can share the same storage locations as A. Similarly, if B is not needed, then C can share the same storage locations as B.

Optional Arguments

NRA — Number of rows of A. (Input)
Default: NRA = SIZE (A,1).

NCA — Number of columns of A. (Input)
Default: NCA = SIZE (A,2).

LDA — Leading dimension of A exactly as specified in the dimension statement of the calling program. (Input)
Default: LDA = SIZE (A,1).

NRB — Number of rows of B. (Input)
NRB must be equal to NRA.
Default: NRB = SIZE (B,1).

NCB — Number of columns of B. (Input)
NCB must be equal to NCA.
Default: NCB = SIZE (B,2).

LDB — Leading dimension of B exactly as specified in the dimension statement of the calling program. (Input)
Default: LDB = SIZE (B,1).

NRC — Number of rows of C. (Input)
NRC must be equal to NRA.
Default: NRC = SIZE (C,1).

NCC — Number of columns of C. (Input)
NCC must be equal to NCA.
Default: NCC = SIZE (C,2).

LDC — Leading dimension of C exactly as specified in the dimension statement of the calling program. (Input)
Default: LDC = SIZE (C,1).

FORTRAN 90 Interface

Generic: CALL HRRRR (A, B, C [, …])

Specific: The specific interface names are S_HRRRR and D_HRRRR.

FORTRAN 77 Interface

Single: CALL HRRRR (NRA, NCA, A, LDA, NRB, NCB, B, LDB, NRC, NCC, C, LDC)

Double: The double precision name is DHRRRR.

Description

The routine HRRRR computes the Hadamard product of two real matrices A and B and returns a real matrix C, where Cij = AijBij.

Example

Compute the Hadamard product of two 4 ×  4 real matrices. The output matrix will be a 4 ×  4 real matrix.

 

 

USE HRRRR_INT

USE WRRRN_INT

 

IMPLICIT NONE

! Declare variables

INTEGER NCA, NCB, NCC, NRA, NRB, NRC

PARAMETER (NCA=4, NCB=4, NCC=4, NRA=4, NRB=4, NRC=4)

!

REAL A(NRA,NCA), B(NRB,NCB), C(NRC,NCC)

! Set values for A

! A = ( -1.0 0.0 -3.0 8.0 )

! ( 2.0 1.0 7.0 2.0 )

! ( 3.0 -2.0 2.0 -6.0 )

! ( 4.0 1.0 -5.0 -8.0 )

!

! Set values for B

! B = ( 2.0 3.0 0.0 -10.0 )

! ( 1.0 -1.0 4.0 2.0 )

! ( -1.0 -2.0 7.0 1.0 )

! ( 2.0 1.0 9.0 0.0 )

!

DATA A/-1.0, 2.0, 3.0, 4.0, 0.0, 1.0, -2.0, 1.0, -3.0, 7.0, 2.0, &

-5.0, 8.0, 2.0, -6.0, -8.0/

DATA B/2.0, 1.0, -1.0, 2.0, 3.0, -1.0, -2.0, 1.0, 0.0, 4.0, 7.0, &

9.0, -10.0, 2.0, 1.0, 0.0/

! Compute Hadamard product of A and B

CALL HRRRR (A, B, C)

! Print results

CALL WRRRN ('C = A (*) B', C)

END

Output

 

C = A (*) B

1 2 3 4

1 -2.00 0.00 0.00 -80.00

2 2.00 -1.00 28.00 4.00

3 -3.00 4.00 14.00 -6.00

4 8.00 1.00 -45.00 0.00