'use strict'

const deepMap = require('../../utils/collection/deepMap')

const number = require('../../utils/number')

function factory (type, config, load, typed) {

/**

* Test whether a value is an integer number.

* The function supports `number`, `BigNumber`, and `Fraction`.

*

* The function is evaluated element-wise in case of Array or Matrix input.

*

* Syntax:

*

* math.isInteger(x)

*

* Examples:

*

* math.isInteger(2) // returns true

* math.isInteger(0) // returns true

* math.isInteger(0.5) // returns false

* math.isInteger(math.bignumber(500)) // returns true

* math.isInteger(math.fraction(4)) // returns true

* math.isInteger('3') // returns true

* math.isInteger([3, 0.5, -2]) // returns [true, false, true]

* math.isInteger(math.complex('2-4i') // throws an error

*

* See also:

*

* isNumeric, isPositive, isNegative, isZero

*

* @param {number | BigNumber | Fraction | Array | Matrix} x Value to be tested

* @return {boolean} Returns true when `x` contains a numeric, integer value.

* Throws an error in case of an unknown data type.

*/

const isInteger = typed('isInteger', {

'number': number.isInteger, // TODO: what to do with isInteger(add(0.1, 0.2)) ?

'BigNumber': function (x) {

return x.isInt()

},

'Fraction': function (x) {

return x.d === 1 && isFinite(x.n)

},

'Array | Matrix': function (x) {

return deepMap(x, isInteger)

}

})

return isInteger

}

exports.name = 'isInteger'

exports.factory = factory