vector string

aaabhish · 11-14-2007, 05:32 AM

hi,

i have a doubt in vector strings what are these vector strings.
and if this is a vector how to find the dimention of these vector or what
is the dimention of this vector.

and how to do vector string things in c language.

keratos · 11-14-2007, 06:04 AM

Dont really understand your English.

Taking a wild guess, are you interesting in 'C' programming constructs?

In particular, vector arrays?

http://www.cppreference.com/cppvector/index.html

osor · 11-14-2007, 01:49 PM

Linked to above is not a C but a C++ vector reference. There really is no C-language vector (there are “arrays” which are contiguous memory areas holding a series of objects of a single type). Up until recently (C99), an array’s length was always determined at compile-time. Now an array’s length may be variable. Still, arrays are much different from vectors (for example, you can’t “grow” or “shrink” arrays).

You can implement your own vector functions in C using the memory allocation functions such as malloc(), calloc(), and realloc(). They will probably not be as type-generic as the C++ template-based stl vectors though (unless you are really creative with your preprocessing).

aaabhish · 11-15-2007, 12:15 PM

thanx osor,
but how will i implement vector function using memory functions melloc, calloc and realloc.
as there mast be some dimention of vectors so here in this case what will be the dimention
of vector after implementing it from malloc like functions.

and yes i m interested in c programming constructs.

rsashok · 11-15-2007, 01:03 PM

How about thit as a template:

Code:

typedef struct
{
   uint32_t   size;
   uint8_t    *data;
} vector_t;

vector_t *create_vector(uint32_t size)
{
   vector_t   *new_vector = NULL;
   
   if ((new_vector = calloc(1, sizeof(vector_t)) != NULL)
   {
       if((new_vector->data = calloc(1, size)) != NULL)
           new_vector->size = size;
   }
   return(new_vector);
}

uint32_t add_vector(vector_t *first, verctor_t *second, vector_t *result)
{
    uint32_t   i, retv;

    if ((first->size == second->size) && (result->size <= first->size))
    {
        for(i = 0; i < first->size; i++)
           result->data[i] = first->data[i] + second->data[i];
        
        retv = !0;
    }
    else
    {
         retv = 0;
    }
   return retv;
}

Go ahead and add whatever you want, tailor to your own needs - only you know what you want.

aaabhish · 11-17-2007, 10:24 AM

what are this uint32_t and uint_8.

Nylex · 11-17-2007, 10:40 AM

Typedefs for 32-bit and 8-bit unsigned integers, I'd imagine.

rsashok · 11-17-2007, 11:16 AM

If you are working on 32-bit computer (and most likely you are then):

Code:

typedef unsigned long uint32_t
typedef unisgned char uint8_t

and so on for the rest of them signed and unsigned. It will make your code more portable, and what is even more important more readable.

keratos · 11-18-2007, 02:12 PM

There are 'C' modules that can be added, to service vector types or quite simply, arrays of arrays (variable length) for that is what a vector is anyway!