Changed the iterator to iterate over the same size tensors in the same order independent of memory layout.

tensoriter.c

@@ -2,19 +2,20 @@
 
 tensoriter_scalar tensoriter_scalar_create(tensor t)
 {
-    /* Creates an iterator over the values of a tensor.
+    /* Creates an iterator over the values of a tensor. If two tensors have the
+     * same size the iterator will always iterate over them in the same order.
      *
      * @param t The tensor to iterate over
      *
-     * @return The iterator
+     * @return The iterator, NULL in case of an error
      */
 	assert(!tensor_is_empty(t));
 
 	tensoriter_scalar it = malloc(sizeof(struct _tensor_scalar_iterator));
 	if (it == NULL) return NULL;
 
-	it->current = t->elements;
-	it->length = t->num_elem;
+	it->t = t;
+	it->index = calloc(sizeof(uint32_t), t->rank);
 
 	return it;
 }
@@ -25,6 +26,7 @@ void tensoriter_scalar_destroy(tensoriter_scalar it)
      *
      * @param it The iterator to destroy
      */
+	free(it->index);
 	free(it);
 }
 
@@ -38,37 +40,49 @@ bool tensoriter_scalar_next(tensoriter_scalar it)
      *
      * @return true if there is a next value, false otherwise
      */
-	if (it->length == 1) {
+    bool end = true;
+
+    for (uint8_t i = 0; i < it->t->rank; i++) {
+        if (it->index[i] < it->t->size[i] - 1) {
+            (it->index[i])++;
+            end = false;
+            break;
+        } else {
+            it->index[i] = 0;
+        }
+    }
+
+	if (end) {
 		tensoriter_scalar_destroy(it);
 		return false;
 	}
 
-	it->current++;
-	it->length--;
-
 	return true;
 }
 
-dtype tensoriter_scalar_get(tensoriter_scalar it)
+dtype tensoriter_scalar_get(tensoriter_scalar it, bool *success)
 {
     /* Gets the current value of the iterator.
      *
      * @param it The iterator to operate on
+     * @param success Is set if not NULL and defines whether the get operation
+     *      was successful
      *
-     * @return A pointer to the current value
+     * @return The current value of the iterator
      */
-	return *(it->current);
+	return tensor_get(it->t, it->index, success);
 }
 
-void tensoriter_scalar_set(tensoriter_scalar it, dtype value)
+bool tensoriter_scalar_set(tensoriter_scalar it, dtype value)
 {
-    /* Sets the current value of the iterator.
+    /* Sets the value of the tensor which the iterator is pointing to at the
+     * moment.
      *
      * @param it The iterator to operate on
      * @param value The value to insert
      *
      */
-	*(it->current) = value;
+	return tensor_set(it->t, it->index, value);
 }
 
 void tensoriter_scalar_map(tensoriter_scalar it, dtype (*func)(dtype))
@@ -80,7 +94,7 @@ void tensoriter_scalar_map(tensoriter_scalar it, dtype (*func)(dtype))
      * @param func The map function that is called
      */
 	do {
-		dtype x = tensoriter_scalar_get(it);
+		dtype x = tensoriter_scalar_get(it, NULL);
 		tensoriter_scalar_set(it, func(x));
 	} while(tensoriter_scalar_next(it));
 }
@@ -93,7 +107,7 @@ void tensoriter_scalar_map_add(tensoriter_scalar it, dtype scalar)
      * @param scalar The value to add
      */
 	do {
-        dtype x = tensoriter_scalar_get(it);
+        dtype x = tensoriter_scalar_get(it, NULL);
 		tensoriter_scalar_set(it, DTYPE_ADD(x, scalar));
 	} while(tensoriter_scalar_next(it));
 }
@@ -106,7 +120,7 @@ void tensoriter_scalar_map_sub(tensoriter_scalar it, dtype scalar)
      * @param scalar The value to subtract
      */
 	do {
-        dtype x = tensoriter_scalar_get(it);
+        dtype x = tensoriter_scalar_get(it, NULL);
 		tensoriter_scalar_set(it, DTYPE_SUB(x, scalar));
 	} while(tensoriter_scalar_next(it));
 }
@@ -119,7 +133,7 @@ void tensoriter_scalar_map_mul(tensoriter_scalar it, dtype scalar)
      * @param scalar The value to multiply
      */
 	do {
-        dtype x = tensoriter_scalar_get(it);
+        dtype x = tensoriter_scalar_get(it, NULL);
 		tensoriter_scalar_set(it, DTYPE_MUL(x, scalar));
 	} while(tensoriter_scalar_next(it));
 }
@@ -132,7 +146,7 @@ void tensoriter_scalar_map_div(tensoriter_scalar it, dtype scalar)
      * @param scalar The value to divide by
      */
 	do {
-        dtype x = tensoriter_scalar_get(it);
+        dtype x = tensoriter_scalar_get(it, NULL);
 		tensoriter_scalar_set(it, DTYPE_DIV(x, scalar));
 	} while(tensoriter_scalar_next(it));
 }

tensoriter.h

@@ -4,16 +4,16 @@
 #include "tensor.h"
 
 typedef struct _tensor_scalar_iterator {
-	dtype *current;
-	uint32_t length;
+	tensor t;
+	uint32_t *index;
 } * tensoriter_scalar;
 
 tensoriter_scalar tensoriter_scalar_create(tensor t);
 void tensoriter_scalar_destroy(tensoriter_scalar it);
 
 bool tensoriter_scalar_next(tensoriter_scalar it);
-dtype tensoriter_scalar_get(tensoriter_scalar it);
-void tensoriter_scalar_set(tensoriter_scalar it, dtype value);
+dtype tensoriter_scalar_get(tensoriter_scalar it, bool *success);
+bool tensoriter_scalar_set(tensoriter_scalar it, dtype value);
 
 void tensoriter_scalar_map(tensoriter_scalar it, dtype (*func)(dtype));
 void tensoriter_scalar_map_add(tensoriter_scalar it, dtype scalar);

tests/tensoriter_test.c

@@ -39,7 +39,9 @@ void tensoriter_test_scalar_get(void)
     uint32_t contained = 0;
     tensoriter_scalar iter = tensoriter_scalar_create(t);
     do {
-        uint32_t value = (uint32_t) tensoriter_scalar_get(iter);
+        bool success;
+        uint32_t value = (uint32_t) tensoriter_scalar_get(iter, &success);
+        tensor_assert(success, "mute");
         tensor_assert(((1 << (value - 1)) & contained) == 0, "mute");
         contained |= 1 << (value - 1);
     } while (tensoriter_scalar_next(iter));