decimal | A high-performance , arbitrary-precision , floating-point | Math library

If you don't want to add a IsNull-function in you SQL (as Nathan_Sav suggested as a comment): There is a IsNull-function in VBA. With that, you can create a simple function that returns for example an empty string (or a 0 or whatever you prefer):

First of all: a Rat with a denominator of 0 is a perfectly legal Rational value. So creating a Rat with a 0 denominator will not throw an exception on creation.

I see two issues really:

• how do you represent a Rat with a denominator of 0 as a string?
• how do you want your program to react to such a Rat?

When you represent a Rats as a string, there is a good chance you will lose precision:

All basic integer types in Java are signed. To be exact, byte, short, int and long are signed big endian two complement integers. That means that they run from - 2^n-1 to 2^n-1 - 1 where n is the number of bits - 8 for a byte (Byte.SIZE in Java), and therefore the range is from -128 to 127.

The number you are using is always an integer; number literals always are. However, the integer is actually the value 0x000000FF in hexadecimals. That cannot be stored as it is higher than 127. You can however do an explicit conversion; your value does consist of 8 bits after all.

The kind of rounding you're asking for isn't a common operation.

In terms of common operations you have two cases (ignoring sign since all your examples are positive):

1. If the value is less than 1, round to significant figures (eg per the link in @quamrana's comment on the question).
2. Else (ie the value is at least 1), round to decimal places in the usual way.

Your final code would reasonably be a function with a simple if-else:

Your implementation should be safe - in theory, all numbers between 0 and MAX_SAFE_INTEGER should have a possibility of appearing, if the engine implementing Math.random uses a completely unbiased algorithm.

But an absolutely unbiased algorithm is not guaranteed by the specification - the numbers chosen are meant to be psuedo random, not truly, completely random. ^{(does such a thing even exist? it's debatable...)} Modern versions V8 and some other implementations use an algorithm with a period on the order of 2 ** 128, larger than MAX_SAFE_INTEGER (2 ** 53 - 1) - but it'd be completely plausible for other implementations (especially older ones) to have a much smaller period, resulting in certain integers within the range being picked much more often than others.

If this is important for your script (which is pretty unlikely in most situations, I'd think), you might consider using a higher-quality random generatior than Math.random - but it's almost certainly not worth worrying about.

The best way to do this is to use custom casts :

https://laravel.com/docs/8.x/eloquent-mutators#castables

So for example

create a ReadableNumber class :

That's not a hexadecimal, it's the scientific notation as evaluated by the toString() method:

Returns the string representation of this BigDecimal, using scientific notation if an exponent is needed.

The E letter denotes the exponent of the number.

In general if you want to format a decimal number, you can use java.text.DecimalFormat.