diff --git a/tensoriterator.c b/tensoriterator.c
index 2f3c406..0a730e9 100644
--- a/tensoriterator.c
+++ b/tensoriterator.c
@@ -2,6 +2,12 @@
 
 tensoriter_scalar tensoriter_scalar_create(tensor t)
 {
+    /* Creates an iterator over the values of a tensor.
+     *
+     * @param t The tensor to iterate over
+     *
+     * @return The iterator
+     */
 	assert(!tensor_is_empty(t));
 
 	tensoriter_scalar it = malloc(sizeof(struct _tensor_scalar_iterator));
@@ -15,29 +21,53 @@ tensoriter_scalar tensoriter_scalar_create(tensor t)
 
 void tensoriter_scalar_destroy(tensoriter_scalar it)
 {
+    /* Destroys an iterator.
+     *
+     * @param it The iterator to destroy
+     */
 	free(it);
 }
 
-uint8_t tensoriter_scalar_next(tensoriter_scalar it)
+bool tensoriter_scalar_next(tensoriter_scalar it)
 {
+    /* Checks whether the given iterator has a next value and sets this value 
+     * as the current value if available. If there is not next value the 
+     * iterator is destroyed and false is returned.
+     *
+     * @param it The iterator to evaluate
+     *
+     * @return true if there is a next value, false otherwise
+     */
 	if (it->length == 1) {
 		tensoriter_scalar_destroy(it);
-		return 0;
+		return false;
 	}
 
 	it->current++;
 	it->length--;
 
-	return 1;
+	return true;
 }
 
 dtype *tensoriter_scalar_get(tensoriter_scalar it)
 {
+    /* Gets the current value of the iterator.
+     *
+     * @param it The iterator to operate on
+     *
+     * @return A pointer to the current value
+     */
 	return it->current;
 }
 
 void tensoriter_scalar_map(tensoriter_scalar it, dtype (*func)(dtype))
 {
+    /* Replaces every value in an iterator with the result of given function
+     * with the old value as a parameter.
+     *
+     * @param it The iterator to operate on
+     * @param func The map function that is called
+     */
 	do {
 		dtype *el = tensoriter_scalar_get(it);
 		*el = func(*el);
@@ -46,6 +76,11 @@ void tensoriter_scalar_map(tensoriter_scalar it, dtype (*func)(dtype))
 
 void tensoriter_scalar_map_add(tensoriter_scalar it, dtype scalar)
 {
+    /* Adds a fixed scalar value to all the values of the iterator.
+     *
+     * @param it The iterator to operate on
+     * @param scalar The value to add
+     */
 	do {
 		DTYPE_ADD(*tensoriter_scalar_get(it), scalar);
 	} while(tensoriter_scalar_next(it));
@@ -53,6 +88,11 @@ void tensoriter_scalar_map_add(tensoriter_scalar it, dtype scalar)
 
 void tensoriter_scalar_map_sub(tensoriter_scalar it, dtype scalar)
 {
+    /* Subtracts a fixed scalar value from all the values of the iterator.
+     *
+     * @param it The iterator to operate on
+     * @param scalar The value to subtract
+     */
 	do {
 		DTYPE_SUB(*tensoriter_scalar_get(it), scalar);
 	} while(tensoriter_scalar_next(it));
@@ -60,6 +100,11 @@ void tensoriter_scalar_map_sub(tensoriter_scalar it, dtype scalar)
 
 void tensoriter_scalar_map_mul(tensoriter_scalar it, dtype scalar)
 {
+    /* Multiplies a fixed scalar value with all the values of the iterator.
+     *
+     * @param it The iterator to operate on
+     * @param scalar The value to multiply
+     */
 	do {
 		DTYPE_MUL(*tensoriter_scalar_get(it), scalar);
 	} while(tensoriter_scalar_next(it));
@@ -67,6 +112,11 @@ void tensoriter_scalar_map_mul(tensoriter_scalar it, dtype scalar)
 
 void tensoriter_scalar_map_div(tensoriter_scalar it, dtype scalar)
 {
+    /* Divides all the values of the iterator by a fixed scalar value.
+     *
+     * @param it The iterator to operate on
+     * @param scalar The value to divide by
+     */
 	do {
 		DTYPE_DIV(*tensoriter_scalar_get(it), scalar);
 	} while(tensoriter_scalar_next(it));
diff --git a/tensoriterator.h b/tensoriterator.h
index 762559d..2de276c 100644
--- a/tensoriterator.h
+++ b/tensoriterator.h
@@ -11,7 +11,7 @@ typedef struct _tensor_scalar_iterator {
 tensoriter_scalar tensoriter_scalar_create(tensor t);
 void tensoriter_scalar_destroy(tensoriter_scalar it);
 
-uint8_t tensoriter_scalar_next(tensoriter_scalar it);
+bool tensoriter_scalar_next(tensoriter_scalar it);
 dtype *tensoriter_scalar_get(tensoriter_scalar it);
 
 void tensoriter_scalar_map(tensoriter_scalar it, dtype (*func)(dtype));