How do I pack to integer values in a double ?

Astricks

How do I pack two integer values in a double ? i.e int x=1000; int y=2000; double z; now I want the first four bytes to be occupied by x and the next 4 by y in Z How do I do that? any shift operators would help? please tell me how do I pack & unpack it?

toxcct

what about using union ?

union U {
double _d;
int _i[2];
};

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Astricks

Thank you for your reply sir, But I do not want an union :(. The matter is, You have a function like this. Imagine you cannot change it's params. It's built by someone and it's used in numerous instances. void testDouble(double d) { cout< Now you say , testDouble(2143250); it prints 2143250. Now I want to send two integer values to this function for other reason. I have two numbres, 1000, 2000. these are ints so takes only 4 bytes. `double 00000000000000000000.....64 now 0000000..32 | 0000.......32 is my idea.` But how do I do that? So that in the function, I can do like, void testDouble(double d) { cout<<(HIGHER32)d; cout<<(LOWER32)d; } get me now?

toxcct

wait, you want to merge 2 ints into a double, or split a double into 2 ints ? BTW be careful, sizeof(int) == 4 only on 32 bits plateforms !

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Astricks

Yes exactly, but I'm happy that sizeof(int) is 4 :) that enough to keep a 4 bytes data :laugh:

toxcct wrote:

you want to merge 2 ints into a double, or split a double into 2 ints ?

Yes. I want this. May be you can try with shift operators :rolleyes:

Chris Losinger

int main(int argc, char* argv[])
{
__int32 i[2];
i[0] = 1000;
i[1] = 2000;

double d = 0;
d = \*(double\*)&i\[0\];

printf("%f\\n", d);

\_\_int32 \*o;
o = (\_\_int32\*)&d;
printf("%d %d\\n", o\[0\], o\[1\]);

return 0;

}

of course, anyone doing something like this would end up in the Daily WTF, for sure.

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David Crow

Is this what you are after:

   int             int

/-+-+-+-+-+-+-+-|-+-+-+-+-+-+-+-\
| | | | | | | | | | | | | | | | |
\-+-+-+-+-+-+-+-|-+-+-+-+-+-+-+-/
double

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"Judge not by the eye but by the heart." - Native American Proverb

toxcct

lol, David, are you moking at newbies ? :rolleyes:

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Astricks

I'll test this & tell you. Thanks. BRB

David Crow

Moking? Do you mean mocking? No, I was just trying to clarify what the intent was by using a visual.

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Astricks

Yes David.

toxcct

DavidCrow wrote:

Moking? Do you mean mocking?

indeed i was. but that's true also that pictures are more clear than words sometimes...

TOXCCT >>> GEII power

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Astricks

Chris, that worked thanks. Now I'm happy I have a way. But if you can still get me a way that will never take part in WTFs that'd be excellent.