This version is out of date, covering development from v9.0.0 to v9.3.0. It is maintained here only for inbound reference links from elsewhere. It is no longer actively updated.

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 Function   [other Function type actions]

 Item   [operators of similar scope]

 Formatting   [other Formatting operators]




This function makes it easier to format numbers. The function returns the associated Number-type attributes value rounded to N decimal places as Number-type data.. If $MyNumber is 268.3289 then:


…sets $MyNumber to 268.33, whilst:

$SomeNumber = $MyNumber.precision(2); 

…sets $OtherNumber to 268.33. The above examples are the equivalent of the older syntax using format():


Literal numbers, e.g. 3.1415927, can also be worked with:

$MyNumber = 5.1415927.precision(2); is 5.14

The above works but the following syntax may seem less ambiguous by using parentheses to delimit the literal number:

$MyNumber =(5.1415927).precision(2); is 5.14

Since Number.precision() was added, format() has been supplemented by a Number.format(). The latter, in single input version equates to Number.precision(). However that Number.format() outputs a String-type, even if that can be coerced back to a number .

The .precision() function can be used to add trailing zeroes to a decimal. If $MyNumber is 214.40, it will display as 214.4 which can be unhelpful if this actually represents £214.40. $MyNumber.precision(2) will return 214.40 but be careful about under-the-hood number/string coercion such as can happen in contexts like $DisplayExpression.

$MyOtherNumber = $MyNumber.precision(2); gives 214.4

$MyString = $MyNumber.precision(2); gives "214.40"

In a $DisplayExpression:

$MyNumber.precision(2); gives "214.40"

$Name+" : "+$MyNumber.precision(2); gives "214.40"

$Name+ " : " + sum(children,$MyNumber).precision(2); 

It may still be easier to use format() as no extra parentheses are required:

$Name+ " : " + format(sum(children,$MyNumber),2);