From 29ed51c50a0cb79c811cf040b086d994366e901d Mon Sep 17 00:00:00 2001
From: margarita0303 <lashina.2000@gmail.com>
Date: Sat, 30 Jul 2022 19:03:43 +0300
Subject: [PATCH] added new parameter iterations to svdGolubKahan

---
 .../space/kscience/kmath/tensors/core/DoubleTensorAlgebra.kt | 4 ++--
 .../space/kscience/kmath/tensors/core/internal/linUtils.kt   | 5 +++--
 2 files changed, 5 insertions(+), 4 deletions(-)

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 8b5e9e470..742a3d7a7 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
@@ -837,7 +837,7 @@ public open class DoubleTensorAlgebra :
         return this.svdGolubKahan()
     }
 
-    public fun StructureND<Double>.svdGolubKahan(): Triple<DoubleTensor, DoubleTensor, DoubleTensor> {
+    public fun StructureND<Double>.svdGolubKahan(iterations: Int = 30): Triple<DoubleTensor, DoubleTensor, DoubleTensor> {
         val size = tensor.dimension
         val commonShape = tensor.shape.sliceArray(0 until size - 2)
         val (n, m) = tensor.shape.sliceArray(size - 2 until size)
@@ -859,7 +859,7 @@ public open class DoubleTensorAlgebra :
                     .slice(matrix.bufferStart until matrix.bufferStart + matrixSize)
                     .toDoubleArray()
             )
-            curMatrix.as2D().svdGolubKahanHelper(uTensors[index].as2D(), sTensorVectors[index], vTensors[index].as2D())
+            curMatrix.as2D().svdGolubKahanHelper(uTensors[index].as2D(), sTensorVectors[index], vTensors[index].as2D(), iterations)
         }
 
         return Triple(uTensor.transpose(), sTensor, vTensor)
diff --git a/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/core/internal/linUtils.kt b/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/core/internal/linUtils.kt
index a6372bc65..0f58cf47c 100644
--- a/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/core/internal/linUtils.kt
+++ b/kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/core/internal/linUtils.kt
@@ -372,7 +372,8 @@ private fun SIGN(a: Double, b: Double): Double {
     else
         return -abs(a)
 }
-internal fun MutableStructure2D<Double>.svdGolubKahanHelper(u: MutableStructure2D<Double>, w: BufferedTensor<Double>, v: MutableStructure2D<Double>) {
+internal fun MutableStructure2D<Double>.svdGolubKahanHelper(u: MutableStructure2D<Double>, w: BufferedTensor<Double>,
+                                                            v: MutableStructure2D<Double>, iterations: Int) {
     val shape = this.shape
     val m = shape.component1()
     val n = shape.component2()
@@ -531,7 +532,7 @@ internal fun MutableStructure2D<Double>.svdGolubKahanHelper(u: MutableStructure2
     var z = 0.0
     var x = 0.0
     for (k in n - 1 downTo 0) {
-        for (its in 1 until 30) {
+        for (its in 1 until iterations) {
             flag = 1
             for (newl in k downTo 0) {
                 nm = newl - 1