The Wikipedia page on it is a good place to start.
To sum up:
floatis represented in 32 bits, with 1 sign bit, 8 bits of exponent, and 23 bits of the significand (or what follows from a scientific-notation number: 2.33728*1012; 33728 is the significand).doubleis represented in 64 bits, with 1 sign bit, 11 bits of exponent, and 52 bits of significand.
By default, Java uses double to represent its floating-point numerals (so a literal 3.14 is typed double). It's also the data type that will give you a much larger number range, so I would strongly encourage its use over float.
There may be certain libraries that actually force your usage of float, but in general - unless you can guarantee that your result will be small enough to fit in float's prescribed range, then it's best to opt with double.
If you require accuracy - for instance, you can't have a decimal value that is inaccurate (like 1/10 + 2/10), or you're doing anything with currency (for example, representing $10.33 in the system), then use a BigDecimal, which can support an arbitrary amount of precision and handle situations like that elegantly.
ELI5:Java. Could someone explain what the data type 'float' is and how/why it should be used? Thanks
When should I use double and when should I use float for Java?
[New CS Student]Trouble differentiating between floats and doubles--why is 23.5 considered a double?
The Wikipedia page on it is a good place to start.
To sum up:
floatis represented in 32 bits, with 1 sign bit, 8 bits of exponent, and 23 bits of the significand (or what follows from a scientific-notation number: 2.33728*1012; 33728 is the significand).doubleis represented in 64 bits, with 1 sign bit, 11 bits of exponent, and 52 bits of significand.
By default, Java uses double to represent its floating-point numerals (so a literal 3.14 is typed double). It's also the data type that will give you a much larger number range, so I would strongly encourage its use over float.
There may be certain libraries that actually force your usage of float, but in general - unless you can guarantee that your result will be small enough to fit in float's prescribed range, then it's best to opt with double.
If you require accuracy - for instance, you can't have a decimal value that is inaccurate (like 1/10 + 2/10), or you're doing anything with currency (for example, representing $10.33 in the system), then use a BigDecimal, which can support an arbitrary amount of precision and handle situations like that elegantly.
A float gives you approx. 6-7 decimal digits precision while a double gives you approx. 15-16. Also the range of numbers is larger for double.
A double needs 8 bytes of storage space while a float needs just 4 bytes.
I'm in the throws of trying to learn Java and am very much a beginner. So, I apologise if this is a daft question. tbh it would probably help if you could explain like I'm a five year old who is very slow on the uptake.
I am learning Java, and am confuse on when to choose double or float for my real numbers or int. It feels like, it doesn’t matter because from my limited experience (with Java) both of them deliver the same results, but I don’t want to go further down the learning curve with Java and have a bad habit of using either messing up my code, and not having a clue as to why. So, when should you use float and double?