number

Number utilities.

Table of Contents #

abbreviate(val[, nDecimalDigits, dictionary]):String #

Abbreviate number to thousands (K), millions (M) or billions (B).

The default value for nDecimalDigits is 1.

Example

abbreviate(123456);     // "123.5K"
abbreviate(12345678);   // "12.3M"
abbreviate(1234567890); // "1.2B"

You can set the amount of decimal digits (default is 1):

abbreviate(543);    // "0.5K"
abbreviate(543, 1); // "0.5K"
abbreviate(543, 2); // "0.54K"
abbreviate(543, 3); // "0.543K"

You can customize the abbreviation by passing a custom "dictionary":

var _ptbrDict = {
    thousands : ' mil',
    millions : ' Mi',
    billions : ' Bi'
};
function customAbbr(val) {
    return abbreviate(val, 1, _ptbrDict);
}

customAbbr(123456); // "123.5 mil"
customAbbr(12345678); // "12.3 Mi"
customAbbr(1234567890); // "1.2 Bi"

currencyFormat(val[, nDecimalDigits, decimalSeparator, thousandsSeparator]):String #

Format a number as currency.

Example:

currencyFormat(1000);              // "1,000.00"
currencyFormat(1000, 1);           // "1,000.0"
currencyFormat(1000, 2, ',', '.'); // "1.000,00"

You can also create a new instance that will have different defaults.

var cur = currencyFormat.create(0, ',', '.');
cur(1000);    // "1.000"
cur(1000, 1); // "1.000,0"
cur(1000, 2); // "1.000,00"

PS: All arguments are required on the currencyFormat.create() method.

enforcePrecision(val, nDecimalDigits):Number #

Enforce a specific amount of decimal digits and also fix floating point rounding issues.

Example:


enforcePrecision(0.615, 2); // 0.62
enforcePrecision(0.625, 2); // 0.63
//floating point rounding "error" (rounds to odd number)
+(0.615).toFixed(2);        // 0.61
+(0.625).toFixed(2);        // 0.63

MAX_INT:Number #

Maximum 32-bit signed integer value. Math.pow(2, 31) - 1

Example:


console.log( MAX_INT ); // 2147483647

MAX_UINT:Number #

Maximum 32-bit unsigned integer value. Math.pow(2, 32) - 1

Example:


console.log( MAX_UINT ); // 4294967295

MIN_INT:Number #

Minimum 32-bit signed integer value. Math.pow(2, 31) * -1.

Example:


console.log( MIN_INT ); // -2147483648

pad(n, minLength):String #

Add padding zeros if n.length < minLength.

Example:


pad(1, 5);      // 00001
pad(12, 5);     // 00012
pad(123, 5);    // 00123
pad(1234, 5);   // 01234
pad(12345, 5);  // 12345
pad(123456, 5); // 123456

rol(val, shift):Number #

Bitwise circular shift left.

More info at Wikipedia#Circular_shift

ror(val, shift):Number #

Bitwise circular shift right.

More info at Wikipedia#Circular_shift

sign(val):Number #

Returns -1 if value is negative and 1 if value is positive. Useful for multiplications.


sign(-123); // -1
sign(123);  // 1

toInt(val):Number #

"Convert" value into an 32-bit integer. Works like Math.floor if val > 0 and Math.ceil if val < 0.

IMPORTANT: val will wrap at number/MIN_INT and number/MAX_INT.

Created because most people don't know bitwise operations and also because this feature is commonly needed.

Perf tests

Example:


toInt(1.25);   // 1
toInt(0.75);   // 0
toInt(-0.55);  // 0
toInt(-5.0001) // -5

toUInt(val):Number #

"Convert" value into an 32-bit unsigned integer.

Works like AS3#uint().

IMPORTANT: val will wrap at 2^32.

Example:


toUInt(1.25);                 // 1
toUInt(0.75);                 // 0
toUInt(-0.55);                // 0
toUInt(-5.0001);              // 4294967291
toUInt(Math.pow(2,32) - 0.5); // 4294967295
toUInt(Math.pow(2,32) + 0.5); // 0

toUInt31(val):Number #

"Convert" value into an 31-bit unsigned integer (since 1 bit is used for sign).

Useful since all bitwise operators besides >>> treat numbers as signed integers.

IMPORTANT: val will wrap at 2^31 and negative numbers will be treated as zero.

Example:


toUInt31(1.25);                 // 1
toUInt31(0.75);                 // 0
toUInt31(-0.55);                // 0
toUInt31(-5.0001);              // 0
toUInt31(Math.pow(2,31) - 0.5); // 21474836470
toUInt31(Math.pow(2,31) + 0.5); // 0

For more usage examples check specs inside /tests folder. Unit tests are the best documentation you can get...

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