R devel - May 2014 - SEXPTYPEs

Dear list,

On a follow up from my previous email, I am now trying to allocate vectors
of length larger than 32-bit in C.
>From the R internals documentation, I read that:
"The sxpinfo header is defined as a 32-bit C structure..."
and
"A SEXPREC is a C structure containing the 32-bit header..."

The question is: does the INTSXP allow vectors larger than 32-bit?


A test example:

//###
int *p_temp;

SEXP root = PROTECT(allocVector(VECSXP, 5));

long long int verylargeinteger;
// something to compute verylargeinteger, > 32-bit

SEXP temp = SET_VECTOR_ELT(root, 0, allocVector(INTSXP, verylargeinteger));
p_temp = INTEGER(temp);
//###

"temp" should be a vector of length > 32-bit, and
"p_temp" should be the
pointer to that vector.

If declaring:
long long int *p_temp;
(but the compiler throws a warning with an incompatible pointer type,
because pointers should be integers of course).

I've looked at all SEXPTYPEs in the R internals, and the only one specific
to integer vectors is INTSXP. Can this be used for vectors of length larger
than 32-bit?

Thank you again, in advance,
Adrian


-- 
Adrian Dusa
University of Bucharest
Romanian Social Data Archive
1, Schitu Magureanu Bd.
050025 Bucharest sector 5
Romania
Tel.:+40 21 3126618 \
        +40 21 3120210 / int.101
Fax: +40 21 3158391

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On 16/05/2014, 4:16 AM, Adrian Du?a wrote:
> Dear list,
>
> On a follow up from my previous email, I am now trying to allocate vectors
> of length larger than 32-bit in C.
>
>>From the R internals documentation, I read that:
> "The sxpinfo header is defined as a 32-bit C structure..."
> and
> "A SEXPREC is a C structure containing the 32-bit header..."
>
> The question is: does the INTSXP allow vectors larger than 32-bit?
>
>
> A test example:
>
> //###
> int *p_temp;
>
> SEXP root = PROTECT(allocVector(VECSXP, 5));
>
> long long int verylargeinteger;
> // something to compute verylargeinteger, > 32-bit
>
> SEXP temp = SET_VECTOR_ELT(root, 0, allocVector(INTSXP, verylargeinteger));
> p_temp = INTEGER(temp);
> //###
>
> "temp" should be a vector of length > 32-bit, and
"p_temp" should be the
> pointer to that vector.
>
> If declaring:
> long long int *p_temp;
> (but the compiler throws a warning with an incompatible pointer type,
> because pointers should be integers of course).
>
> I've looked at all SEXPTYPEs in the R internals, and the only one
specific
> to integer vectors is INTSXP. Can this be used for vectors of length larger
> than 32-bit?
Yes, see the section on "Long Vectors" in chapter 12.

Duncan Murdoch
>
> Thank you again, in advance,
> Adrian
>
>