Fixed tests.

kmath-functions/src/commonTest/kotlin/space/kscience/kmath/functions/ListPolynomialTest.kt

@@ -12,7 +12,7 @@ import kotlin.test.*
 class ListPolynomialTest {
     @Test
     fun test_Polynomial_Int_plus() {
-        RationalField.listPolynomial {
+        RationalField.listPolynomialSpace {
             assertEquals(
                 ListPolynomial(Rational(-22, 9), Rational(-8, 9), Rational(-8, 7)),
                 ListPolynomial(Rational(5, 9), Rational(-8, 9), Rational(-8, 7)) + -3,
@@ -52,7 +52,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Polynomial_Int_minus() {
-        RationalField.listPolynomial {
+        RationalField.listPolynomialSpace {
             assertEquals(
                 ListPolynomial(Rational(32, 9), Rational(-8, 9), Rational(-8, 7)),
                 ListPolynomial(Rational(5, 9), Rational(-8, 9), Rational(-8, 7)) - -3,
@@ -92,7 +92,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Polynomial_Int_times() {
-        IntModuloRing(35).listPolynomial {
+        IntModuloRing(35).listPolynomialSpace {
             assertEquals(
                 ListPolynomial(34, 2, 1, 20, 2),
                 ListPolynomial(22, 26, 13, 15, 26) * 27,
@@ -107,7 +107,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Int_Polynomial_plus() {
-        RationalField.listPolynomial {
+        RationalField.listPolynomialSpace {
             assertEquals(
                 ListPolynomial(Rational(-22, 9), Rational(-8, 9), Rational(-8, 7)),
                 -3 + ListPolynomial(Rational(5, 9), Rational(-8, 9), Rational(-8, 7)),
@@ -147,7 +147,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Int_Polynomial_minus() {
-        RationalField.listPolynomial {
+        RationalField.listPolynomialSpace {
             assertEquals(
                 ListPolynomial(Rational(32, 9), Rational(-8, 9), Rational(-8, 7)),
                 3 - ListPolynomial(Rational(-5, 9), Rational(8, 9), Rational(8, 7)),
@@ -187,7 +187,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Int_Polynomial_times() {
-        IntModuloRing(35).listPolynomial {
+        IntModuloRing(35).listPolynomialSpace {
             assertEquals(
                 ListPolynomial(34, 2, 1, 20, 2),
                 27 * ListPolynomial(22, 26, 13, 15, 26),
@@ -202,7 +202,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Polynomial_Constant_plus() {
-        RationalField.listPolynomial {
+        RationalField.listPolynomialSpace {
             assertEquals(
                 ListPolynomial(Rational(-22, 9), Rational(-8, 9), Rational(-8, 7)),
                 ListPolynomial(Rational(5, 9), Rational(-8, 9), Rational(-8, 7)) + Rational(-3),
@@ -242,7 +242,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Polynomial_Constant_minus() {
-        RationalField.listPolynomial {
+        RationalField.listPolynomialSpace {
             assertEquals(
                 ListPolynomial(Rational(32, 9), Rational(-8, 9), Rational(-8, 7)),
                 ListPolynomial(Rational(5, 9), Rational(-8, 9), Rational(-8, 7)) - Rational(-3),
@@ -282,7 +282,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Polynomial_Constant_times() {
-        IntModuloRing(35).listPolynomial {
+        IntModuloRing(35).listPolynomialSpace {
             assertEquals(
                 ListPolynomial(34, 2, 1, 20, 2),
                 ListPolynomial(22, 26, 13, 15, 26) * 27.asConstant(),
@@ -297,7 +297,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Constant_Polynomial_plus() {
-        RationalField.listPolynomial {
+        RationalField.listPolynomialSpace {
             assertEquals(
                 ListPolynomial(Rational(-22, 9), Rational(-8, 9), Rational(-8, 7)),
                 Rational(-3) + ListPolynomial(Rational(5, 9), Rational(-8, 9), Rational(-8, 7)),
@@ -337,7 +337,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Constant_Polynomial_minus() {
-        RationalField.listPolynomial {
+        RationalField.listPolynomialSpace {
             assertEquals(
                 ListPolynomial(Rational(32, 9), Rational(-8, 9), Rational(-8, 7)),
                 Rational(3) - ListPolynomial(Rational(-5, 9), Rational(8, 9), Rational(8, 7)),
@@ -377,7 +377,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Constant_Polynomial_times() {
-        IntModuloRing(35).listPolynomial {
+        IntModuloRing(35).listPolynomialSpace {
             assertEquals(
                 ListPolynomial(34, 2, 1, 20, 2),
                 27 * ListPolynomial(22, 26, 13, 15, 26),
@@ -392,7 +392,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Polynomial_unaryMinus() {
-        RationalField.listPolynomial {
+        RationalField.listPolynomialSpace {
             assertEquals(
                 ListPolynomial(Rational(-5, 9), Rational(8, 9), Rational(8, 7)),
                 -ListPolynomial(Rational(5, 9), Rational(-8, 9), Rational(-8, 7)),
@@ -407,7 +407,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Polynomial_Polynomial_plus() {
-        RationalField.listPolynomial {
+        RationalField.listPolynomialSpace {
             // (5/9 - 8/9 x - 8/7 x^2) + (-5/7 + 5/1 x + 5/8 x^2) ?= -10/63 + 37/9 x - 29/56 x^2
             assertEquals(
                 ListPolynomial(Rational(-10, 63), Rational(37, 9), Rational(-29, 56)),
@@ -440,7 +440,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Polynomial_Polynomial_minus() {
-        RationalField.listPolynomial {
+        RationalField.listPolynomialSpace {
             // (5/9 - 8/9 x - 8/7 x^2) - (-5/7 + 5/1 x + 5/8 x^2) ?= 80/63 - 53/9 x - 99/56 x^2
             assertEquals(
                 ListPolynomial(Rational(80, 63), Rational(-53, 9), Rational(-99, 56)),
@@ -473,7 +473,7 @@ class ListPolynomialTest {
     }
     @Test
     fun test_Polynomial_Polynomial_times() {
-        IntModuloRing(35).listPolynomial {
+        IntModuloRing(35).listPolynomialSpace {
             // (1 + x + x^2) * (1 - x + x^2) ?= 1 + x^2 + x^4
             assertEquals(
                 ListPolynomial(1, 0, 1, 0, 1),

kmath-functions/src/commonTest/kotlin/space/kscience/kmath/test/misc/IntModulo.kt

@@ -0,0 +1,140 @@
+/*
+ * Copyright 2018-2021 KMath contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package space.kscience.kmath.test.misc
+
+import space.kscience.kmath.functions.ListPolynomial
+import space.kscience.kmath.functions.ListPolynomialSpace
+import space.kscience.kmath.misc.UnstableKMathAPI
+import space.kscience.kmath.operations.Ring
+
+
+class IntModulo {
+    val residue: Int
+    val modulus: Int
+
+    @PublishedApi
+    internal constructor(residue: Int, modulus: Int, toCheckInput: Boolean = true) {
+        if (toCheckInput) {
+            require(modulus != 0) { "modulus can not be zero" }
+            this.modulus = if (modulus < 0) -modulus else modulus
+            this.residue = residue.mod(modulus)
+        } else {
+            this.residue = residue
+            this.modulus = modulus
+        }
+    }
+
+    constructor(residue: Int, modulus: Int) : this(residue, modulus, true)
+
+    operator fun unaryPlus(): IntModulo = this
+    operator fun unaryMinus(): IntModulo =
+        IntModulo(
+            if (residue == 0) 0 else modulus - residue,
+            modulus,
+            toCheckInput = false
+        )
+    operator fun plus(other: IntModulo): IntModulo {
+        require(modulus == other.modulus) { "can not add two residue different modulo" }
+        return IntModulo(
+            (residue + other.residue) % modulus,
+            modulus,
+            toCheckInput = false
+        )
+    }
+    operator fun plus(other: Int): IntModulo =
+        IntModulo(
+            (residue + other) % modulus,
+            modulus,
+            toCheckInput = false
+        )
+    operator fun minus(other: IntModulo): IntModulo {
+        require(modulus == other.modulus) { "can not subtract two residue different modulo" }
+        return IntModulo(
+            (residue - other.residue) % modulus,
+            modulus,
+            toCheckInput = false
+        )
+    }
+    operator fun minus(other: Int): IntModulo =
+        IntModulo(
+            (residue - other) % modulus,
+            modulus,
+            toCheckInput = false
+        )
+    operator fun times(other: IntModulo): IntModulo {
+        require(modulus == other.modulus) { "can not multiply two residue different modulo" }
+        return IntModulo(
+            (residue * other.residue) % modulus,
+            modulus,
+            toCheckInput = false
+        )
+    }
+    operator fun times(other: Int): IntModulo =
+        IntModulo(
+            (residue * other) % modulus,
+            modulus,
+            toCheckInput = false
+        )
+    operator fun div(other: IntModulo): IntModulo {
+        require(modulus == other.modulus) { "can not divide two residue different modulo" }
+        val (reciprocalCandidate, gcdOfOtherResidueAndModulus) = bezoutIdentityWithGCD(other.residue, modulus)
+        require(gcdOfOtherResidueAndModulus == 1) { "can not divide to residue that has non-trivial GCD with modulo" }
+        return IntModulo(
+            (residue * reciprocalCandidate) % modulus,
+            modulus,
+            toCheckInput = false
+        )
+    }
+    operator fun div(other: Int): IntModulo {
+        val (reciprocalCandidate, gcdOfOtherResidueAndModulus) = bezoutIdentityWithGCD(other, modulus)
+        require(gcdOfOtherResidueAndModulus == 1) { "can not divide to residue that has non-trivial GCD with modulo" }
+        return IntModulo(
+            (residue * reciprocalCandidate) % modulus,
+            modulus,
+            toCheckInput = false
+        )
+    }
+    override fun equals(other: Any?): Boolean =
+        when (other) {
+            is IntModulo -> residue == other.residue && modulus == other.modulus
+            else -> false
+        }
+
+    override fun hashCode(): Int = residue.hashCode()
+
+    override fun toString(): String = "$residue mod $modulus"
+}
+
+@Suppress("EXTENSION_SHADOWED_BY_MEMBER", "OVERRIDE_BY_INLINE", "NOTHING_TO_INLINE")
+@OptIn(UnstableKMathAPI::class)
+class IntModuloRing : Ring<IntModulo> {
+
+    val modulus: Int
+
+    constructor(modulus: Int) {
+        require(modulus != 0) { "modulus can not be zero" }
+        this.modulus = if (modulus < 0) -modulus else modulus
+    }
+
+    override inline val zero: IntModulo get() = IntModulo(0, modulus, toCheckInput = false)
+    override inline val one: IntModulo get() = IntModulo(1, modulus, toCheckInput = false)
+
+    fun number(arg: Int) = IntModulo(arg, modulus, toCheckInput = false)
+
+    override inline fun add(left: IntModulo, right: IntModulo): IntModulo = left + right
+    override inline fun multiply(left: IntModulo, right: IntModulo): IntModulo = left * right
+
+    override inline fun IntModulo.unaryMinus(): IntModulo = -this
+    override inline fun IntModulo.plus(arg: IntModulo): IntModulo = this + arg
+    override inline fun IntModulo.minus(arg: IntModulo): IntModulo = this - arg
+    override inline fun IntModulo.times(arg: IntModulo): IntModulo = this * arg
+    inline fun IntModulo.div(arg: IntModulo): IntModulo = this / arg
+}
+
+fun ListPolynomialSpace<IntModulo, IntModuloRing>.ListPolynomial(vararg coefs: Int): ListPolynomial<IntModulo> =
+    ListPolynomial(coefs.map { IntModulo(it, ring.modulus) })
+fun IntModuloRing.ListPolynomial(vararg coefs: Int): ListPolynomial<IntModulo> =
+    ListPolynomial(coefs.map { IntModulo(it, modulus) })

kmath-functions/src/commonTest/kotlin/space/kscience/kmath/test/misc/misc.kt

@@ -8,4 +8,22 @@ package space.kscience.kmath.test.misc
 import kotlin.math.abs
 
 
+data class BezoutIdentityWithGCD<T>(val first: T, val second: T, val gcd: T)
+
 tailrec fun gcd(a: Long, b: Long): Long = if (a == 0L) abs(b) else gcd(b % a, a)
+
+fun bezoutIdentityWithGCD(a: Int, b: Int): BezoutIdentityWithGCD<Int> =
+    when {
+        a < 0 && b < 0 -> with(bezoutIdentityWithGCDInternalLogic(-a, -b, 1, 0, 0, 1)) { BezoutIdentityWithGCD(-first, -second, gcd) }
+        a < 0 -> with(bezoutIdentityWithGCDInternalLogic(-a, b, 1, 0, 0, 1)) { BezoutIdentityWithGCD(-first, second, gcd) }
+        b < 0 -> with(bezoutIdentityWithGCDInternalLogic(a, -b, 1, 0, 0, 1)) { BezoutIdentityWithGCD(first, -second, gcd) }
+        else -> bezoutIdentityWithGCDInternalLogic(a, b, 1, 0, 0, 1)
+    }
+
+internal tailrec fun bezoutIdentityWithGCDInternalLogic(a: Int, b: Int, m1: Int, m2: Int, m3: Int, m4: Int): BezoutIdentityWithGCD<Int> =
+    if (b == 0) BezoutIdentityWithGCD(m1, m3, a)
+    else {
+        val quotient = a / b
+        val reminder = a % b
+        bezoutIdentityWithGCDInternalLogic(b, reminder, m2, m1 - quotient * m2, m4, m3 - quotient * m4)
+    }