Path: utzoo!utgpu!utstat!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!pasteur!ames!elroy!hacgate!ashtate!dbase!awd
From: awd@dbase.UUCP (Alastair Dallas)
Newsgroups: comp.lang.c
Subject: Re: C
Summary: Malloc and pointers
Message-ID: <27@dbase.UUCP>
Date: 7 Mar 89 02:17:42 GMT
References: <1256@dukeac.UUCP> <9743@smoke.BRL.MIL> <9501@bloom-beacon.MIT.EDU> <1989Feb28.170504.17123@utzoo.uucp>
Organization: Ashton Tate Devlopment Center Glendale, Calif.
Lines: 30

In article <1989Feb28.170504.17123@utzoo.uucp>, henry@utzoo.uucp (Henry Spencer) writes:
> In article <9501@bloom-beacon.MIT.EDU> yphotons@athena.mit.edu (Sun Warrior) writes:
> >I would like to know how to set an array (float) to a certain size...
> >... I would first like to be able to type in the size and
> >then set the array...
> 
> You can't.  With certain (unhelpful) exceptions, the dimensions of C arrays
> must be constants.  You can get much the same effect using malloc() and
> pointers, although it is more complicated.

It's not very complicated at all:

	float *p;
	int i;
	int n;

	printf("Enter the size of the array:");
	scanf("%d", &n);
	p = (float *) calloc(n, sizeof(float));
	
	for (i=0; i<n; i++)
		p[i] = 0.0;

	...

	free(p);

What's the big deal?

/alastair/