From e110253d8f38171b91d4417c115713585e9faa29 Mon Sep 17 00:00:00 2001
From: Roland Grinis <roland.grinis@grinisrit.com>
Date: Thu, 13 May 2021 19:26:18 +0100
Subject: [PATCH] remove cov from tensors API

---
 .../kmath/tensors/api/AnalyticTensorAlgebra.kt         | 10 ----------
 .../kscience/kmath/tensors/core/DoubleTensorAlgebra.kt | 10 +++++++++-
 2 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/api/AnalyticTensorAlgebra.kt b/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/api/AnalyticTensorAlgebra.kt
index 1db986e77..e58af14db 100644
--- a/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/api/AnalyticTensorAlgebra.kt
+++ b/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/api/AnalyticTensorAlgebra.kt
@@ -67,16 +67,6 @@ public interface AnalyticTensorAlgebra<T> : TensorPartialDivisionAlgebra<T> {
      */
     public fun Tensor<T>.variance(dim: Int, keepDim: Boolean): Tensor<T>
 
-    /**
-     * Returns the covariance matrix M of given vectors.
-     *
-     * M[i, j] contains covariance of i-th and j-th given vectors
-     *
-     * @param tensors the [List] of 1-dimensional tensors with same shape
-     * @return the covariance matrix
-     */
-    public fun cov(tensors: List<Tensor<T>>): Tensor<T>
-
     //For information: https://pytorch.org/docs/stable/generated/torch.exp.html
     public fun Tensor<T>.exp(): Tensor<T>
 
diff --git a/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/core/DoubleTensorAlgebra.kt b/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/core/DoubleTensorAlgebra.kt
index c1694644f..78989f1f3 100644
--- a/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/core/DoubleTensorAlgebra.kt
+++ b/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/core/DoubleTensorAlgebra.kt
@@ -629,7 +629,15 @@ public open class DoubleTensorAlgebra :
         return ((x - x.mean()) * (y - y.mean())).mean() * n / (n - 1)
     }
 
-    override fun cov(tensors: List<Tensor<Double>>): DoubleTensor {
+    /**
+     * Returns the covariance matrix M of given vectors.
+     *
+     * M[i, j] contains covariance of i-th and j-th given vectors
+     *
+     * @param tensors the [List] of 1-dimensional tensors with same shape
+     * @return the covariance matrix
+     */
+    public fun cov(tensors: List<Tensor<Double>>): DoubleTensor {
         check(tensors.isNotEmpty()) { "List must have at least 1 element" }
         val n = tensors.size
         val m = tensors[0].shape[0]