Add suppport for clip

Author: martinRenou

include/xframe/xaxis_math.hpp

@@ -65,7 +65,7 @@ namespace xf
     // Needs a fix in xtensor
     //using xt::maximum;
     //using xt::minimum;
-    //using xt::clip;
+    using xt::clip;
     using xt::sign;
 
     using xt::exp;

include/xframe/xframe_expression.hpp

@@ -9,9 +9,10 @@
 #ifndef XFRAME_XFRAME_EXPRESSION_HPP
 #define XFRAME_XFRAME_EXPRESSION_HPP
 
-#include "xtensor/xexpression.hpp"
 #include "xtl/xtype_traits.hpp"
 
+#include "xtensor/xexpression.hpp"
+
 namespace xf
 {
     struct xvariable_expression_tag {};
@@ -40,4 +41,28 @@ namespace xf
     };
 }
 
+namespace xt
+{
+    namespace extension
+    {
+        template <>
+        struct expression_tag_and<xf::xvariable_expression_tag, xoptional_expression_tag>
+        {
+            using type = xf::xvariable_expression_tag;
+        };
+
+        template <>
+        struct expression_tag_and<xoptional_expression_tag, xf::xvariable_expression_tag>
+            : expression_tag_and<xf::xvariable_expression_tag, xoptional_expression_tag>
+        {
+        };
+
+        template <>
+        struct expression_tag_and<xf::xvariable_expression_tag, xf::xvariable_expression_tag>
+        {
+            using type = xf::xvariable_expression_tag;
+        };
+    }
+}
+
 #endif

test/test_xvariable_math.cpp

@@ -345,15 +345,31 @@ namespace xf
         EXPECT_EQ(std::min(sa, a.select(sel)), minimum(sa, a).select(sel));
     }*/
 
-    // TODO: enable this once clamp functor is fixed in xtensor 
-    /*TEST(xvariable_math, clip)
+    TEST(xvariable_math, clip)
     {
+        auto missing = xtl::missing<double>();
+        using data_type = xt::xoptional_assembly<xt::xarray<double>, xt::xarray<bool>>;
+
         variable_type a = make_test_variable();
-        dict_type sel = make_selector_aa();
-        xtl::xoptional<double> floor = 1.2;
-        xtl::xoptional<double> ceil = 2.4;
-        EXPECT_EQ(clip(a.select(sel), floor, ceil), clip(a, floor, ceil).select(sel));
-    }*/
+
+        variable_type res = clip(a, 2., 8.0);
+        data_type expected = {{      2,   2, missing},
+                              {missing,   5,       6},
+                              {      7,   8,       8}};
+        EXPECT_EQ(res.data(), expected);
+
+        variable_type res2 = clip(a, missing, missing);
+        data_type expected2 = {{missing, missing, missing},
+                               {missing, missing, missing},
+                               {missing, missing, missing}};
+        EXPECT_EQ(res2.data(), expected2);
+
+        variable_type res3 = clip(a, missing, 4.);
+        data_type expected3 = {{missing, missing, missing},
+                               {missing, missing, missing},
+                               {missing, missing, missing}};
+        EXPECT_EQ(res3.data(), expected3);
+    }
 
     TEST(xvariable_math, sign)
     {