import assert from 'assert' import math from '../../../../src/bundleAny' import approx from '../../../../tools/approx' const pi = math.pi const asech = math.asech const sech = math.sech const complex = math.complex const matrix = math.matrix const unit = math.unit const bigmath = math.create({ number: 'BigNumber', precision: 20 }) const biggermath = math.create({ precision: 22 }) const predmath = math.create({ predictable: true }) const asechBig = bigmath.asech const Big = bigmath.bignumber describe('asech', function () { it('should return the hyperbolic arcsec of a boolean', function () { assert.strictEqual(asech(true), 0) assert.strictEqual(asech(false), Infinity) }) it('should return the hyperbolic arcsec of a number', function () { approx.deepEqual(asech(-0.5), complex(1.3169578969, pi)) approx.deepEqual(asech(2), complex(0, pi / 3)) // assert.ok(isNaN(asech(-0.5))) // assert.ok(isNaN(asech(2))) assert.strictEqual(asech(0), Infinity) approx.equal(asech(0.25), 2.0634370688955605467272811726201) approx.equal(asech(0.5), 1.31695789692481670862504634730797) approx.equal(asech(0.75), 0.7953654612239056305278909331478) assert.strictEqual(asech(1), 0) }) it('should return the hyperbolic arcsec of a number when predictable:true', function () { assert.strictEqual(typeof predmath.asech(2), 'number') assert(isNaN(predmath.asech(2))) }) it('should return the hyperbolic arcsec of a bignumber', function () { const arg1 = Big(0) const arg2 = Big(0.25) assert.deepStrictEqual(asechBig(arg1).toString(), 'Infinity') assert.deepStrictEqual(asechBig(arg2), Big('2.0634370688955605467')) assert.deepStrictEqual(asechBig(Big(0.5)), Big('1.3169578969248167086')) assert.deepStrictEqual(asechBig(Big(0.75)), Big('0.79536546122390563049')) assert.deepStrictEqual(asechBig(Big(1)), Big(0)) // Make sure arg was not changed assert.deepStrictEqual(arg1, Big(0)) assert.deepStrictEqual(arg2, Big(0.25)) /* out of range */ assert.ok(asech(Big(-1)).isNaN()) assert.ok(asech(Big(2)).isNaN()) }) it('should be the inverse function of hyperbolic sec', function () { approx.equal(asech(sech(-1)), 1) approx.equal(asech(sech(0)), 0) approx.equal(asech(sech(0.1)), 0.1) approx.equal(asech(sech(0.5)), 0.5) approx.equal(asech(sech(2)), 2) }) it('should be the inverse function of bignumber sech', function () { assert.deepStrictEqual(asechBig(bigmath.sech(Big(-1))), Big(1)) assert.deepStrictEqual(asechBig(bigmath.sech(Big(0))), Big(0)) assert.deepStrictEqual(asechBig(bigmath.sech(Big(0.5))), Big('0.49999999999999999995')) assert.deepStrictEqual(asechBig(bigmath.sech(Big(2))), Big(2)) /* Pass in more digits to pi. */ assert.deepStrictEqual(asechBig(biggermath.sech(Big(0.1))), Big('0.10000000000000000012')) }) it('should return the arcsech of a complex number', function () { approx.deepEqual(asech(complex('2+3i')), complex(0.23133469857397, -1.420410722467035)) approx.deepEqual(asech(complex('2-3i')), complex(0.23133469857397, 1.420410722467035)) approx.deepEqual(asech(complex('-2+3i')), complex(0.23133469857397, -1.72118193112275858)) approx.deepEqual(asech(complex('-2-3i')), complex(0.23133469857397, 1.72118193112275858)) approx.deepEqual(asech(complex('1+i')), complex(0.5306375309525178, -1.11851787964370594)) approx.deepEqual(asech(complex('i')), complex(0.881373587019543, -1.570796326794897)) approx.deepEqual(asech(complex('2')), complex(0, pi / 3)) assert.deepStrictEqual(asech(complex('1')), complex(-0, 0)) approx.deepEqual(asech(complex('0.5')), complex(1.3169578969248, 0)) assert.deepStrictEqual(asech(complex('0')), complex(Infinity, Infinity)) approx.deepEqual(asech(complex('-0.5')), complex(1.3169578969248, pi)) approx.deepEqual(asech(complex('-1')), complex(0, pi)) }) it('should throw an error if called with a unit', function () { assert.throws(function () { asech(unit('45deg')) }) assert.throws(function () { asech(unit('5 celsius')) }) }) it('should throw an error if called with a string', function () { assert.throws(function () { asech('string') }) }) it('should calculate the arcsec element-wise for arrays and matrices', function () { const asech01 = [Infinity, 0] assert.deepStrictEqual(asech([0, 1]), asech01) assert.deepStrictEqual(asech(matrix([0, 1])), matrix(asech01)) }) it('should throw an error in case of invalid number of arguments', function () { assert.throws(function () { asech() }, /TypeError: Too few arguments/) assert.throws(function () { asech(1, 2) }, /TypeError: Too many arguments/) }) it('should LaTeX asech', function () { const expression = math.parse('asech(1)') assert.strictEqual(expression.toTex(), '\\mathrm{sech}^{-1}\\left(1\\right)') }) })