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description
Integers and floats to rule the world!

Numbers

There are two basic kinds of numbers in CFML: integers (whole numbers) and floats (have a decimal point). Internally, each CFML engine treats them uniquely and backs up each numerical value as a Java class: java.lang.Double or java.lang.Integer.

TypeSize (bits)Min ValueMax Value
Integer32-2,147,483,648 (-231)2,147,483,647 (231 - 1)
TypeSize (bits)Significant BitsExponent BitsDecimal Digits
Double64531115-16

{% hint style="danger" %} Lucee stores all numerical values as Doubles {% endhint %}

{% hint style="danger" %} Adobe stores integers as Integer and floats as Doubles {% endhint %}

{% hint style="success" %} Tip: If you are dealing with currency or tracking precision, please read about precisionEvaluate() to represent big numbers and precision results: https://cfdocs.org/precisionevaluate {% endhint %}

a = 1;
b = 50.1;
writeOutput( a * b );

Also, note that CFML will do the auto-casting for you when converting between integers and doubles.

Numeric Type

Once we start looking at functions/closures and lambdas, you will see that you can also type the incoming arguments and results of functions. You also won't need to type it with integer or float, just as numeric:

numeric function add( numeric a, numeric b ){
    return a + b;
}

Operators & Functions

CFML offers tons of mathematical operators and functions: https://cfdocs.org/math%2Dfunctions

abs aCos arrayAvg
arraySum aSin atn
bitAnd bitMaskClear bitMaskRead
bitMaskSet bitNot bitOr
bitSHLN bitSHRN bitXor
ceiling cos decrementValue
expt fix floor
formatBaseN incrementValue inputBaseN
int log log10
max min pi
precisionEvaluate rand randomize
randRange round sgn
sin sqr tan

Casting/Parsing

CFML also has a toNumeric() function that you can use to cast a value to a number using different radixes. 

toNumeric( "29.5" )
toNumeric( "FF0011", "hex" )
toNumeric( "1010", "bin" )

The parseNumber() is also used to convert a string number into a numeral system (https://cfdocs.org/parsenumber)

{% hint style="info" %} In a positional numeral system, the radix or base is the number of unique digits, including the digit zero, used to represent numbers. For example, for the decimal system (the most common system in use today) the radix is ten, because it uses the ten digits from 0 through 9. {% endhint %}

Is it a number?

CFML provides the isNumeric() function to determine if the passed value can be converted to a numeric value. 

isNumeric( 23 ) // yes
isNumeric( "twenty" ) // no
isNumeric( 5e2 ) // yes

Repeating Instructions

Number variables can be used to repeat instructions. Like in many other languages, CFML supports the for, while and loop constructs:

for( var i = 0; i <= 10; i++ ){
    writeOutput( "Showing day " & i );
}

i =1;
while( i <= 10 ){
    writeOutput( "Showing day " & i++ );
}

{% hint style="info" %} Please note that the syntax varies from tag to script, so refer to the docs for subtle differences. Please also note that you can iterate over structures, arrays, queries, and objects in CFML; we will see this in later sections.

See https://cfdocs.org/cfloop, https://cfdocs.org/cfwhile for more information {% endhint %}