My text book doesn't go into much detail on floats and doubles. I know what a float is. I've read some wiki's on doubles but I'm still a bit confused, and have a couple related questions, that are not in my textbook.
1. What is the difference between a float and a double? What are the advantages/disadvantages of using either.
2. what is the difference between using %lf and %f ?
Thanks
> 1. What is the difference between a float and a double? What are the advantages/disadvantages of using either.
Doubles have more digits of precision, and a larger range of exponents.
Short answer, you can store larger numbers with more accuracy.
> 2. what is the difference between using %lf and %f ?
You have to use the right one when using scanf to read floats or doubles.
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The difference is the precision, a double has a larger mantissa (actually larger than double the size). In a float it's 23 bits and in a double it's 52 bits. The range is a bit larger than that since the signed bit is not part of the mantissa and it's normalized as well.
The format specifiers are dedicated to the each type, so %f is for float and %lf is for doubles.
Double precision floating-point format - Wikipedia, the free encyclopedia
The difference has to do with precision. Read What every computer scientist should know about floating point arithmetic. Specifically look for the section entitled "Precision".Originally Posted by Bobaflex
For printf nothing. For scanf and family it specifies whether or not you are reading in a double "%lf" or a float "%f".
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