Integer overflow for looping over large vector in C? -



Integer overflow for looping over large vector in C? -

we can utilize loop iterate on vector in c, example:

int len = length(x); (int i=0; i<len; i++) { double val = real(x)[i]; }

this seems work fine, don' understand why. according wikipedia default int type ranges −32767 +32767. why still work vectors longer that?

does r somehow override int long int? there maximum length of vector code support?

you misreading wikipedia. here more finish quote (emphasis mine):

at least in [−32767,+32767] range

on modern platforms (at to the lowest degree powerful plenty run r), int @ to the lowest degree 32 bits wide, gives range of [−2147483647,+2147483647] or more.

additionally, r's ?integer has next say:

note current implementations of r utilize 32-bit integers integer vectors, range of representable integers restricted +/-2*10^9: doubles can hold much larger integers exactly.

finally, ?.machine say:

integer.max - largest integer can represented. 2147483647.

c

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