What's the difference, in C and Objective-C, between using Float64 and long?
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4Did you check the documentation? – SLaks May 23 '11 at 16:26
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long is integral (no decimals); Float64 (or double) is floating-point.
SLaks
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Long is an integral format, usually on 64bits, but platform-dependant. Float64 is a floating point format, written on 64its (usually double), but guaranteed to be on 64bits.
Macmade
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Like mention before one is a integer and one is a float. The basic difference is the ability to have a decimal point, which a real/float can have and integer can not have. If all things were equal a float is stored in science notation, while an integer is not. A float would allow for a much much bigger number and has no need for being unsigned. A double is a long float, and long is long integer so they are larger values. Also in ANSI C there is no Float64.
Joe Tyman
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There isn't a "science notation" format for storing binary values. You can't define a word using the same word - the sentence "a long is a long integer" does not make sense. – iheanyi Apr 02 '14 at 15:28
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@iheanyi In binary scientific notation is represented by use of a sign bit in between the second and first byte. The first byte becomes the exponent. Actually a long is short for a long integer. A long integer uses more bytes than an int(which is short for integer). – Joe Tyman Apr 09 '14 at 00:16
