diff --git a/kmath-core/src/commonMain/kotlin/scientifik/kmath/operations/Complex.kt b/kmath-core/src/commonMain/kotlin/scientifik/kmath/operations/Complex.kt
index a97afdb6b..107bb2f24 100644
--- a/kmath-core/src/commonMain/kotlin/scientifik/kmath/operations/Complex.kt
+++ b/kmath-core/src/commonMain/kotlin/scientifik/kmath/operations/Complex.kt
@@ -56,9 +56,7 @@ data class Complex(val re: Double, val im: Double) : FieldElement<Complex, Compl
     val abs: Double
         get() = kotlin.math.sqrt(square)
 
-    companion object {
-
-    }
+    companion object
 }
 
 fun Double.toComplex() = Complex(this, 0.0)
\ No newline at end of file
diff --git a/kmath-core/src/commonMain/kotlin/scientifik/kmath/operations/NumberAlgebra.kt b/kmath-core/src/commonMain/kotlin/scientifik/kmath/operations/NumberAlgebra.kt
index 2dc6d3228..953f2e326 100644
--- a/kmath-core/src/commonMain/kotlin/scientifik/kmath/operations/NumberAlgebra.kt
+++ b/kmath-core/src/commonMain/kotlin/scientifik/kmath/operations/NumberAlgebra.kt
@@ -24,9 +24,7 @@ inline class Real(val value: Double) : FieldElement<Double, Real, RealField> {
 
     override val context get() = RealField
 
-    companion object {
-
-    }
+    companion object
 }
 
 /**
diff --git a/kmath-core/src/commonMain/kotlin/scientifik/kmath/structures/NDStructure.kt b/kmath-core/src/commonMain/kotlin/scientifik/kmath/structures/NDStructure.kt
index 3c422797c..d9601a5d4 100644
--- a/kmath-core/src/commonMain/kotlin/scientifik/kmath/structures/NDStructure.kt
+++ b/kmath-core/src/commonMain/kotlin/scientifik/kmath/structures/NDStructure.kt
@@ -102,6 +102,20 @@ class DefaultStrides private constructor(override val shape: IntArray) : Strides
     override val linearSize: Int
         get() = strides[shape.size]
 
+
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (other !is DefaultStrides) return false
+
+        if (!shape.contentEquals(other.shape)) return false
+
+        return true
+    }
+
+    override fun hashCode(): Int {
+        return shape.contentHashCode()
+    }
+
     companion object {
         private val defaultStridesCache = HashMap<IntArray, Strides>()