What is Double? (C#)
Possible Duplicate:
What is the difference between Decimal, Float and Double in C#?
Today I'm wondering about Double in .Net. I've used it with Int32 the past days and started wondering what the max value is.
The MSDN page for Double.MaxValue says 1.7976931348623157E+308 . I'm pretty sure I'm reading that wrong.
How many bytes does Double take up (in memory)?
What is the actual maximum number (explain the the E+308)?
Is Double.MaxValue bigger than UInt32 ? Bigger than UInt64 ?
And while we are at it, what is the difference between Float and Double ?
Basically,
Double is 64 bit floating point value and float is a 32 bit. So double is able to store twice big value as of float.
http://msdn.microsoft.com/en-us/library/678hzkk9(v=vs.80).aspx http://msdn.microsoft.com/en-us/library/b1e65aza(v=vs.71).aspx
Just read the top lines on the links, you'll get an idea.
About E+308 : though 2^64 is far less that 1e+308 , you must consider that double is not "precise" number, it has only a few significant digits (precision), so it does not need to store all ~308 digits. With this logic behind the double structure, it can contain numbers up to e+308 in 64 bits.
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