How To Access 3/4 Dimensional Arrays Using Pointers

From: Christopher M. Lusardi (clusardi2k_at_aol.com)
Date: 01/29/04 

Date: 29 Jan 2004 12:12:41 -0800

Hello,

   Can you tell me (with good examples) how to access 3 and 4 dimensional
Fortran arrays using pointers in C/C++? My program uses two languages. I have
arrays defined in Fortran. In C I am given the base address of the Fortran
arrays. How do I get the address of individual elements

EG: The following is the lower half of the addresses of a three dimensional
array.

Fortran declaration
int_tes (3,2,2)

Addresses
int_tes (1,1,1) = 548
int_tes (1,1,2) = 656
int_tes (1,2,1) = 602
int_tes (1,2,2) = 710
int_tes (2,1,1) = 566
int_tes (2,1,2) = 674
int_tes (2,2,1) = 620
int_tes (2,2,2) = 728
int_tes (3,1,1) = 584
int_tes (3,1,2) = 692
int_tes (3,2,1) = 638
int_tes (3,2,2) = 746

548 + 108 = 656 to go from element 1,1,1 to 1,1,2
548 + 18 = 566 to go from element 1,1,1 to 2,1,1
548 + 54 = 602 to go from element 1,1,1 to 1,2,1

The size of an integer is 3 bytes.

(1,,) (2,,) (3,,)
548 656 566 674 584 692
602 710 620 728 638 746

                   Thank you,
                   Christopher Lusardi

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