Handling of prefix + and -.

Author: MaxSagebaum

include/cpp2taylor.h2

@@ -63,6 +63,23 @@ taylor: <R, dim: int> type  = {
         return sub(o, 0.0, 0.0); // Primal values are not required.
     }
 
+    // Overload for simple handling of prefix +.
+    operator+: (this) -> taylor = {
+        return this;
+    }
+
+    // Overload for simple handling of prefix -.
+    operator-: (this) -> taylor = {
+        r: taylor = ();
+
+        (copy k:= 1)
+        while k <= dim next k += 1 {
+            r.v[k - 1] = -v[k - 1];
+        }
+
+        return r;
+    }
+
     add: (this, o: taylor, v0: R, o0: R) -> taylor = {
         r: taylor = ();
 

regression-tests/pure2-autodiff-higher-order.cpp2

@@ -65,6 +65,14 @@ ad_test: @autodiff<"order=6"> @print type = {
         r = x + x * y;
     }
 
+    prefix_add: (x: double, y: double) -> (r: double) = {
+        r = +x + y;
+    }
+
+    prefix_sub: (x: double, y: double) -> (r: double) = {
+        r = -x + y;
+    }
+
     func: (x: double, y: double) -> (ret: double) = {
       ret = x + y;
     }
@@ -216,6 +224,8 @@ main: () = {
     write_output("x * y / x", x, x_d, y, y_d, ad_name::ad_test::mul_div_2_d(x, x_d, y, y_d));
     write_output("x * (x + y)", x, x_d, y, y_d, ad_name::ad_test::mul_add_d(x, x_d, y, y_d));
     write_output("x + x * y", x, x_d, y, y_d, ad_name::ad_test::add_mul_d(x, x_d, y, y_d));
+    write_output("+x + y)", x, x_d, y, y_d, ad_name::ad_test::prefix_add_d(x, x_d, y, y_d));
+    write_output("-x + y)", x, x_d, y, y_d, ad_name::ad_test::prefix_sub_d(x, x_d, y, y_d));
     write_output("x * func(x, y)", x, x_d, y, y_d, ad_name::ad_test::func_call_d(x, x_d, y, y_d));
     write_output("x * func_outer(x, y)", x, x_d, y, y_d, ad_name::ad_test::func_outer_call_d(x, x_d, y, y_d));
     write_output("sin(x - y)", x, x_d, y, y_d, ad_name::ad_test::sin_call_d(x, x_d, y, y_d));

regression-tests/pure2-autodiff.cpp2

@@ -62,6 +62,14 @@ ad_test: @autodiff @print type = {
         r = x + x * y;
     }
 
+    prefix_add: (x: double, y: double) -> (r: double) = {
+        r = +x + y;
+    }
+
+    prefix_sub: (x: double, y: double) -> (r: double) = {
+        r = -x + y;
+    }
+
     func: (x: double, y: double) -> (ret: double) = {
       ret = x + y;
     }
@@ -213,6 +221,8 @@ main: () = {
     write_output("x * y / x", x, x_d, y, y_d, ad_name::ad_test::mul_div_2_d(x, x_d, y, y_d));
     write_output("x * (x + y)", x, x_d, y, y_d, ad_name::ad_test::mul_add_d(x, x_d, y, y_d));
     write_output("x + x * y", x, x_d, y, y_d, ad_name::ad_test::add_mul_d(x, x_d, y, y_d));
+    write_output("+x + y)", x, x_d, y, y_d, ad_name::ad_test::prefix_add_d(x, x_d, y, y_d));
+    write_output("-x + y)", x, x_d, y, y_d, ad_name::ad_test::prefix_sub_d(x, x_d, y, y_d));
     write_output("x * func(x, y)", x, x_d, y, y_d, ad_name::ad_test::func_call_d(x, x_d, y, y_d));
     write_output("x * func_outer(x, y)", x, x_d, y, y_d, ad_name::ad_test::func_outer_call_d(x, x_d, y, y_d));
     write_output("sin(x - y)", x, x_d, y, y_d, ad_name::ad_test::sin_call_d(x, x_d, y, y_d));

regression-tests/test-results/gcc-13-c++2b/pure2-autodiff-higher-order.cpp.execution

@@ -94,6 +94,22 @@ diff(x + x * y) at (x = 2.000000, x_d = ( 1.000000 0.000000 0.000000 0.000000 0.
   d4 = 0.000000
   d5 = 0.000000
   d6 = 0.000000
+diff(+x + y)) at (x = 2.000000, x_d = ( 1.000000 0.000000 0.000000 0.000000 0.000000 0.000000 ), y = 3.000000, y_d = ( 2.000000 0.000000 0.000000 0.000000 0.000000 0.000000 )):
+  r = 5.000000
+  d1 = 3.000000
+  d2 = 0.000000
+  d3 = 0.000000
+  d4 = 0.000000
+  d5 = 0.000000
+  d6 = 0.000000
+diff(-x + y)) at (x = 2.000000, x_d = ( 1.000000 0.000000 0.000000 0.000000 0.000000 0.000000 ), y = 3.000000, y_d = ( 2.000000 0.000000 0.000000 0.000000 0.000000 0.000000 )):
+  r = 1.000000
+  d1 = 1.000000
+  d2 = 0.000000
+  d3 = 0.000000
+  d4 = 0.000000
+  d5 = 0.000000
+  d6 = 0.000000
 diff(x * func(x, y)) at (x = 2.000000, x_d = ( 1.000000 0.000000 0.000000 0.000000 0.000000 0.000000 ), y = 3.000000, y_d = ( 2.000000 0.000000 0.000000 0.000000 0.000000 0.000000 )):
   r = 10.000000
   d1 = 11.000000

regression-tests/test-results/gcc-13-c++2b/pure2-autodiff.cpp.execution

@@ -10,6 +10,8 @@ diff(x / y / y) at (x = 2.000000, x_d = 1.000000, y = 3.000000, y_d = 2.000000)
 diff(x * y / x) at (x = 2.000000, x_d = 1.000000, y = 3.000000, y_d = 2.000000) = (r = 3.000000, r_d = 2.000000)
 diff(x * (x + y)) at (x = 2.000000, x_d = 1.000000, y = 3.000000, y_d = 2.000000) = (r = 10.000000, r_d = 11.000000)
 diff(x + x * y) at (x = 2.000000, x_d = 1.000000, y = 3.000000, y_d = 2.000000) = (r = 8.000000, r_d = 8.000000)
+diff(+x + y)) at (x = 2.000000, x_d = 1.000000, y = 3.000000, y_d = 2.000000) = (r = 5.000000, r_d = 3.000000)
+diff(-x + y)) at (x = 2.000000, x_d = 1.000000, y = 3.000000, y_d = 2.000000) = (r = 1.000000, r_d = 1.000000)
 diff(x * func(x, y)) at (x = 2.000000, x_d = 1.000000, y = 3.000000, y_d = 2.000000) = (r = 10.000000, r_d = 11.000000)
 diff(x * func_outer(x, y)) at (x = 2.000000, x_d = 1.000000, y = 3.000000, y_d = 2.000000) = (r = 10.000000, r_d = 11.000000)
 diff(sin(x - y)) at (x = 2.000000, x_d = 1.000000, y = 3.000000, y_d = 2.000000) = (r = -0.841471, r_d = -0.540302)