One more question: The original C source code uses gotos. Does a "return" statement in C mean just leave the routine, or does it also return back to the next statement after the goto? I would assume that it does not continue after a goto statement, but this code is so convoluted I can't be sure what it intended to do just by looking at the code.
Phil. ----- Original Message ----- From: "Terry" <[EMAIL PROTECTED]> To: "NZ Borland Developers Group - Delphi List" <[EMAIL PROTECTED]> Sent: Monday, April 19, 2004 12:18 PM Subject: Re: [DUG] Converting some code from C > Pointers and arrays are essentially equivalent in c. And pointer > arithmatic works like array indexation, so ... > > *(snorm+n) = *(snorm+n-1)*(float)(2*n-1)/(float)n; > > and > > snorm[n] = *(snorm+n-1)*(float)(2*n-1)/(float)n; > > and > > snorm[n] = snorm[n-1]*(float)(2*n-1)/(float)n; > > are all equivalent statements. > > A reason you may wish to use the pure pointer form is where you don't > want to pass an array and index offset into a function, you can just > point to an element. And p++ will increment the pointer to the next > array element (probably the reason p is used rather than snorm directly). > > Terry > > > Phil Middlemiss wrote: > > > > >I'm converting some code from some ugly C. The code defines one particular > >array, and a constant like this: > > > >static float snorm[169]; > >static float *p = snorm; > > > >and then later has an assignment: > > > >*snorm = 1.0; > > > >and then again later (n is an integer iterator): > > > >*(snorm+n) = *(snorm+n-1)*(float)(2*n-1)/(float)n; > > > >The question is this: It looks like the code is simply assigning values to > >an array, so why bother with the pointers? Elsewhere the code uses arrays > >normally (ie. indexing them with the square brackets) so that makes me think > >maybe this is doing something other than just putting values into the array. > >Also, I'm assuming that the "p" variable is just a pointer into snorm? > > > >Can anyone make this clear for me? > > > >Cheers, > >Phil. > > > >_______________________________________________ > >Delphi mailing list > >[EMAIL PROTECTED] > >http://ns3.123.co.nz/mailman/listinfo/delphi > > > > > > > > _______________________________________________ > Delphi mailing list > [EMAIL PROTECTED] > http://ns3.123.co.nz/mailman/listinfo/delphi > _______________________________________________ Delphi mailing list [EMAIL PROTECTED] http://ns3.123.co.nz/mailman/listinfo/delphi
