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# How many bytes is float?

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?

sizeof(float)

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Usually 32 bits (4 bytes).

When in doubt, check sizeof(float).

Kami no Itte ga ore ni zettai naru!

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It dependends on the precision.

It can be 16-bit (float) or 32-bit (double). Anyone correct me if i''m wrong.

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quote:
Original post by Blue Phoenix
It dependends on the precision.

It can be 16-bit (float) or 32-bit (double). Anyone correct me if i''m wrong.

As others have said, the only definitive answer is sizeof(float). But I believe that it''s often 32-bit for float, and 64-bit for double.

John B

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sizeof() only gives you the size of the object in terms of char, sizeof(char) is always one. You should check
std::numeric_limits<char>::digits
to work out the number of bits in a char

[edited by - Jingo on February 15, 2004 9:58:28 AM]

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DUDE! You have 6 questions shown on the page of this forum RIGHT NOW, and 4/6 could have been easily answered by a forum search, or by using Google Groups! And 1 of the remaining two was a problem whose solution you found yourself (one has to wonder if you had really tried enough before posting).

The sum of the views for those 6 questions is 448! That''s a lot of time spent on reading trivial questions.

Cédric

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quote:
Original post by Cedric
DUDE! You have 6 questions shown on the page of this forum RIGHT NOW, and 4/6 could have been easily answered by a forum search, or by using Google Groups! And 1 of the remaining two was a problem whose solution you found yourself (one has to wonder if you had really tried enough before posting).

The sum of the views for those 6 questions is 448! That''s a lot of time spent on reading trivial questions.

Cédric

You sound like me.

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quote:
Original post by The C modest god
?

Do we have twenty questions to guess which language and platform you''re using?

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Be careful all: in java, a char is 2 bytes.

Java of course has a "byte" keyword to represent the 8 bit entity. Java focuses on (unicode, etc) 16 bit versions of characters, "chars"...

But yes, in C/C++, a byte is 8 bits wide.

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quote:
Original post by superdeveloper
But yes, in C/C++, a byte is 8 bits wide.

No, the number of bits in a C++ byte is undefined.

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quote:
Original post by Jingo
No, the number of bits in a C++ byte is undefined.
You mean the number of bits in a C++ char? Because byte is defined to be 8 bits, much like nibble is defined as 4 bits, independ of the platform or the language.

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quote:

You mean the number of bits in a C++ char? Because byte is defined to be 8 bits, much like nibble is defined as 4 bits, independ of the platform or the language.

In C++ a char is defined to be one byte. A byte is not neccessarily 8-bits, although for all intents and purposes you are probably safe assuming that nowadays. Likewise, a nybble is defined to be half a byte, not neccessarily four bits.

In any case, I think we''re all agreed that the answer to the OP is sizeof(float), at least in C++.

(I don''t really know if there is an "official" definations for byte, nybble, et cetera, so I''m basically going off of foldoc.org''s entries for the same).