Add shape for each

src/include/rtg/raw_data.hpp

@@ -3,11 +3,10 @@
 #define RTG_GUARD_RAW_DATA_HPP
 
 #include <rtg/tensor_view.hpp>
+#include <rtg/requires.hpp>
 
 namespace rtg {
 
-#define RTG_REQUIRES(...) class = typename std::enable_if<(__VA_ARGS__)>::type
-
 struct raw_data_base
 {
 };

src/include/rtg/requires.hpp

+#ifndef RTG_GUARD_RTGLIB_REQUIRES_HPP
+#define RTG_GUARD_RTGLIB_REQUIRES_HPP
+
+#include <type_traits>
+
+namespace rtg {
+
+template<bool... Bs>
+struct and_
+: std::is_same<and_<Bs...>, and_<(Bs || true)...>>
+{};
+
+#define RTG_REQUIRES(...) class = typename std::enable_if<and_<__VA_ARGS__, true>{}>::type
+
+} // namespace rtg
+
+#endif

src/include/rtg/shape.hpp

@@ -4,6 +4,7 @@
 #include <vector>
 #include <cassert>
 #include <ostream>
+#include <numeric>
 
 #include <rtg/errors.hpp>
 
@@ -60,6 +61,14 @@ struct shape
 
     std::size_t index(std::initializer_list<std::size_t> l) const;
     std::size_t index(const std::vector<std::size_t>& l) const;
+    
+    template<class Iterator>
+    std::size_t index(Iterator start, Iterator last) const
+    {
+        assert(std::distance(start, last) <= this->lens().size());
+        assert(this->lens().size() == this->strides().size());
+        return std::inner_product(start, last, this->strides().begin(), std::size_t{0});
+    }
 
     // Map element index to space index
     std::size_t index(std::size_t i) const;

src/include/rtg/shape_for_each.hpp

+#ifndef RTG_GUARD_RTGLIB_SHAPE_FOR_EACH_HPP
+#define RTG_GUARD_RTGLIB_SHAPE_FOR_EACH_HPP
+
+#include <rtg/shape.hpp>
+#include <algorithm>
+
+namespace rtg {
+
+template<class F>
+void shape_for_each(const rtg::shape& s, F f)
+{
+    // Ensure calls to f use const ref to vector
+    auto call = [&f](const std::vector<std::size_t>& i) { f(i); };
+    std::vector<std::size_t> indices(s.lens().size());
+    for(std::size_t i = 0;i < s.elements();i++) {
+        std::transform(s.strides().begin(),
+                           s.strides().end(),
+                           s.lens().begin(),
+                           indices.begin(),
+                           [&](std::size_t stride, std::size_t len) { return (i / stride) % len; });
+        call(indices);
+    }
+}
+
+
+} // namespace rtg
+
+#endif

src/include/rtg/tensor_view.hpp

@@ -3,6 +3,7 @@
 
 #include <rtg/shape.hpp>
 #include <rtg/float_equal.hpp>
+#include <rtg/requires.hpp>
 
 #include <iostream>
 
@@ -25,18 +26,30 @@ struct tensor_view
 
     const T* data() const { return this->m_data; }
 
-    template <class... Ts>
+    template <class... Ts, RTG_REQUIRES(std::is_integral<Ts>{}...)>
     const T& operator()(Ts... xs) const
     {
-        return m_data[m_shape.index({xs...})];
+        return m_data[m_shape.index({static_cast<std::size_t>(xs)...})];
     }
 
-    template <class... Ts>
+    template <class... Ts, RTG_REQUIRES(std::is_integral<Ts>{}...)>
     T& operator()(Ts... xs)
     {
         return m_data[m_shape.index({static_cast<std::size_t>(xs)...})];
     }
 
+    template <class Iterator, RTG_REQUIRES(not std::is_integral<Iterator>{})>
+    const T& operator()(Iterator start, Iterator last) const
+    {
+        return m_data[m_shape.index(start, last)];
+    }
+
+    template <class Iterator, RTG_REQUIRES(not std::is_integral<Iterator>{})>
+    T& operator()(Iterator start, Iterator last)
+    {
+        return m_data[m_shape.index(start, last)];
+    }
+
     T& operator[](std::size_t i)
     {
         assert(!this->empty() && i < this->size());

src/shape.cpp

@@ -63,7 +63,8 @@ std::size_t shape::index(const std::vector<std::size_t>& l) const
 std::size_t shape::index(std::size_t i) const
 {
     assert(this->lens().size() == this->strides().size());
-    return std::inner_product(
+    if (this->packed()) return i;
+    else return std::inner_product(
         this->lens().begin(),
         this->lens().end(),
         this->strides().begin(),