From f9500f44ec6fc811a17e76104a9bea7ed6f790cc Mon Sep 17 00:00:00 2001
From: Andrei Kislitsyn <kisandy@yandex.ru>
Date: Fri, 12 Mar 2021 13:50:06 +0300
Subject: [PATCH] new tensor def

---
 .../kscience/kmath/tensors/BufferTensor.kt    | 28 +++++++++++++++++++
 .../kmath/tensors/RealTensorAlgebra.kt        | 14 +++++-----
 2 files changed, 35 insertions(+), 7 deletions(-)
 create mode 100644 kmath-core/src/commonMain/kotlin/space/kscience/kmath/tensors/BufferTensor.kt

diff --git a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/tensors/BufferTensor.kt b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/tensors/BufferTensor.kt
new file mode 100644
index 000000000..4d8aea32c
--- /dev/null
+++ b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/tensors/BufferTensor.kt
@@ -0,0 +1,28 @@
+package space.kscience.kmath.tensors
+
+import space.kscience.kmath.linear.BufferMatrix
+import space.kscience.kmath.linear.RealMatrixContext.toBufferMatrix
+import space.kscience.kmath.nd.MutableNDBuffer
+import space.kscience.kmath.nd.as2D
+import space.kscience.kmath.structures.MutableBuffer
+import space.kscience.kmath.structures.toList
+
+public open class BufferTensor<T>(
+    override val shape: IntArray,
+    buffer: MutableBuffer<T>
+) :
+    TensorStructure<T>,
+    MutableNDBuffer<T>(
+        TensorStrides(shape),
+        buffer
+    )
+
+
+public fun <T : Any> BufferTensor<T>.toBufferMatrix(): BufferMatrix<T> {
+    return BufferMatrix(shape[0], shape[1], this.buffer)
+}
+
+public fun  <T : Any> BufferMatrix<T>.BufferTensor(): BufferTensor<T> {
+    return BufferTensor(intArrayOf(rowNum, colNum), buffer)
+}
+
diff --git a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/tensors/RealTensorAlgebra.kt b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/tensors/RealTensorAlgebra.kt
index a5c00e8ec..e38056097 100644
--- a/kmath-core/src/commonMain/kotlin/space/kscience/kmath/tensors/RealTensorAlgebra.kt
+++ b/kmath-core/src/commonMain/kotlin/space/kscience/kmath/tensors/RealTensorAlgebra.kt
@@ -1,19 +1,19 @@
 package space.kscience.kmath.tensors
 
+import space.kscience.kmath.linear.BufferMatrix
+import space.kscience.kmath.linear.RealMatrixContext.toBufferMatrix
 import space.kscience.kmath.nd.MutableNDBuffer
+import space.kscience.kmath.nd.as2D
+import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.RealBuffer
 import space.kscience.kmath.structures.array
+import space.kscience.kmath.structures.toList
 
 
 public class RealTensor(
-    override val shape: IntArray,
+    shape: IntArray,
     buffer: DoubleArray
-) :
-    TensorStructure<Double>,
-    MutableNDBuffer<Double>(
-        TensorStrides(shape),
-        RealBuffer(buffer)
-    )
+) : BufferTensor<Double>(shape, RealBuffer(buffer))
 
 public class RealTensorAlgebra : TensorPartialDivisionAlgebra<Double, RealTensor> {