Re: how to pass a 1 dimension array pointer to a function taking a 2 dimensinoal array pointer?

Instead of using an array of pointers to a vector, use a pointer to an array
of vectors:

typedef float (*X)[3];

*or* :

F (reinterpret_cast<float (*)[3]> (zz));

--
Sylvain Lafontaine, ing.
MVP - Technologies Virtual-PC
E-mail: sylvain aei ca (fill the blanks, no spam please)


"JD" <jdt_young@xxxxxxxxx> wrote in message
news:eSiakhYcHHA.3484@xxxxxxxxxxxxxxxxxxxxxxx
Hi,

I have a very old library with a file prototype shown as below:

void F(float x[][3])

I want to pass a one dimension array as shown below:

float *z;
...
typedef float X[][3];
F(reinterpret_cast<X>(zz));

But the compiler complains that "cannot convert from 'float *' to 'float
[][3]'". Is there any other way to achieve the purpose? I just don't
want to copy my 1 dimension array to a 2 dimension array before calling F.
That requires lots of computational time.

The library is so old that it still used multiple dimensional structures.

Thanks for any help.

JD


.

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