Merge branch 'thrust-for-each' into 'master'

add for_each fixes and presentation

See merge request correaa/boost-multi!1763

Author: correaa

talk/.gitignore

@@ -7,5 +7,5 @@
 *.pdf
 *.fdb_latexmk
 *.fls
-*.synctex.gz
-
+*.synctex*
+*.vrb

talk/presentation.tex

@@ -193,4 +193,35 @@
 \end{frame}
 
 
+\begin{frame}[fragile]{Algorithms}
+  Take a 64x64x64 array ($\sim 250$k elements) \lstinline|A|, apply a compute-bound op.
+
+  \only<1>{
+    \begin{lstlisting}
+for(auto&& plane : A) {
+  for(auto&& row : plane) {
+    for(auto&& elem : row) {
+      elem = op(elem);
+    }
+  }
+}
+    \end{lstlisting}
+  }
+
+  \only<2>{
+    \begin{lstlisting}
+std::for_each(A.begin(), A.end(), [](auto&& plane) {
+  for(auto&& row : plane) {
+    for(auto&& elem : row) {
+      elem = op(elem);
+    }
+  }
+});
+    \end{lstlisting}
+  }
+
+  timing: \textbf{0.0026 sec}
+\end{frame}
+
+
 \end{document}

test/for_each.cpp

@@ -62,6 +62,17 @@ auto main() -> int {  // NOLINT(bugprone-exception-escape)
 		auto cpu_own = multi::array<T, 3>({64, 64, 64}, 0);
 
 		auto&& cpu = cpu_own();
+        {
+			auto_timer const _{"triple nested for"};
+			for(auto&& plane : cpu) {  // NOLINT(modernize-use-ranges)
+				for(auto&& row : plane) {                             // NOLINT(altera-unroll-loops)
+					for(auto&& elem : row) {                          // NOLINT(altera-unroll-loops)
+						elem += std::sqrt(std::pow(elem, 1.5) + std::sin(elem));
+					}
+				}
+			}
+		}
+
 		{
 			auto_timer const _{"std::for_each"};
 			std::for_each(cpu.begin(), cpu.end(), [](auto&& plane) {  // NOLINT(modernize-use-ranges)