diff --git a/kmath-noa/src/main/java/space/kscience/kmath/noa/JNoa.java b/kmath-noa/src/main/java/space/kscience/kmath/noa/JNoa.java
index 4b9aa492a..a5c9ba75b 100644
--- a/kmath-noa/src/main/java/space/kscience/kmath/noa/JNoa.java
+++ b/kmath-noa/src/main/java/space/kscience/kmath/noa/JNoa.java
@@ -182,10 +182,10 @@ class JNoa {
 
     public static native long unaryMinus(long tensorHandle);
 
-    public static native long absTensor(long tensorHandle);
-
     public static native long transposeTensor(long tensorHandle, int i, int j);
 
+    public static native long absTensor(long tensorHandle);
+
     public static native long expTensor(long tensorHandle);
 
     public static native long lnTensor(long tensorHandle);
@@ -246,7 +246,7 @@ class JNoa {
 
     public static native long argMaxTensor(long tensorHandle, int dim, boolean keepDim);
 
-    public static native long flattenTensor(long tensorHandle);
+    public static native long flattenTensor(long tensorHandle, int startDim, int endDim);
 
     public static native long matmul(long lhs, long rhs);
 
diff --git a/kmath-noa/src/main/kotlin/space/kscience/kmath/noa/algebras.kt b/kmath-noa/src/main/kotlin/space/kscience/kmath/noa/algebras.kt
index 36de8abf3..ec91436d6 100644
--- a/kmath-noa/src/main/kotlin/space/kscience/kmath/noa/algebras.kt
+++ b/kmath-noa/src/main/kotlin/space/kscience/kmath/noa/algebras.kt
@@ -124,8 +124,8 @@ protected constructor(protected val scope: NoaScope) :
     override fun Tensor<T>.argMax(dim: Int, keepDim: Boolean): NoaIntTensor =
         NoaIntTensor(scope, JNoa.argMaxTensor(tensor.tensorHandle, dim, keepDim))
 
-    public fun Tensor<T>.flatten(): TensorType =
-        wrap(JNoa.flattenTensor(tensor.tensorHandle))
+    public fun Tensor<T>.flatten(startDim: Int, endDim: Int): TensorType =
+        wrap(JNoa.flattenTensor(tensor.tensorHandle, startDim, endDim))
 
     public fun Tensor<T>.randDiscrete(low: Long, high: Long): TensorType =
         wrap(JNoa.randintLike(tensor.tensorHandle, low, high))
diff --git a/kmath-noa/src/main/resources/space_kscience_kmath_noa_JNoa.h b/kmath-noa/src/main/resources/space_kscience_kmath_noa_JNoa.h
index a9a5866c2..adc2ab5ae 100644
--- a/kmath-noa/src/main/resources/space_kscience_kmath_noa_JNoa.h
+++ b/kmath-noa/src/main/resources/space_kscience_kmath_noa_JNoa.h
@@ -655,14 +655,6 @@ JNIEXPORT void JNICALL Java_space_kscience_kmath_noa_JNoa_minusTensorAssign
 JNIEXPORT jlong JNICALL Java_space_kscience_kmath_noa_JNoa_unaryMinus
   (JNIEnv *, jclass, jlong);
 
-/*
- * Class:     space_kscience_kmath_noa_JNoa
- * Method:    absTensor
- * Signature: (J)J
- */
-JNIEXPORT jlong JNICALL Java_space_kscience_kmath_noa_JNoa_absTensor
-  (JNIEnv *, jclass, jlong);
-
 /*
  * Class:     space_kscience_kmath_noa_JNoa
  * Method:    transposeTensor
@@ -671,6 +663,14 @@ JNIEXPORT jlong JNICALL Java_space_kscience_kmath_noa_JNoa_absTensor
 JNIEXPORT jlong JNICALL Java_space_kscience_kmath_noa_JNoa_transposeTensor
   (JNIEnv *, jclass, jlong, jint, jint);
 
+/*
+ * Class:     space_kscience_kmath_noa_JNoa
+ * Method:    absTensor
+ * Signature: (J)J
+ */
+JNIEXPORT jlong JNICALL Java_space_kscience_kmath_noa_JNoa_absTensor
+  (JNIEnv *, jclass, jlong);
+
 /*
  * Class:     space_kscience_kmath_noa_JNoa
  * Method:    expTensor
@@ -914,10 +914,10 @@ JNIEXPORT jlong JNICALL Java_space_kscience_kmath_noa_JNoa_argMaxTensor
 /*
  * Class:     space_kscience_kmath_noa_JNoa
  * Method:    flattenTensor
- * Signature: (J)J
+ * Signature: (JII)J
  */
 JNIEXPORT jlong JNICALL Java_space_kscience_kmath_noa_JNoa_flattenTensor
-  (JNIEnv *, jclass, jlong);
+  (JNIEnv *, jclass, jlong, jint, jint);
 
 /*
  * Class:     space_kscience_kmath_noa_JNoa