INFINITY working for float and double (#460)

src/ngraph/util.cpp

@@ -270,3 +270,32 @@ ngraph::FpropCache ngraph::cache_fprop(std::shared_ptr<ngraph::Function> fprop,
 
     return fprop_cache;
 }
+
+namespace ngraph
+{
+    template <>
+    float parse_string<float>(const std::string& s)
+    {
+        const char* tmp = s.c_str();
+        char* end;
+        float result = strtof(tmp, &end);
+        if (*end != 0)
+        {
+            throw std::runtime_error("Could not parse literal '" + s + "'");
+        }
+        return result;
+    }
+
+    template <>
+    double parse_string<double>(const std::string& s)
+    {
+        const char* tmp = s.c_str();
+        char* end;
+        double result = strtod(tmp, &end);
+        if (*end != 0)
+        {
+            throw std::runtime_error("Could not parse literal '" + s + "'");
+        }
+        return result;
+    }
+}

src/ngraph/util.hpp

@@ -183,6 +183,13 @@ namespace ngraph
         return result;
     }
 
+    /// template specializations for float and double to handle INFINITY, -INFINITY
+    /// and NaN values.
+    template <>
+    float parse_string<float>(const std::string& s);
+    template <>
+    double parse_string<double>(const std::string& s);
+
     /// Parses a list of strings containing literals of the underlying type.
     template <typename T>
     std::vector<T> parse_string(const std::vector<std::string>& ss)

test/serialize.cpp

@@ -26,6 +26,7 @@
 
 using namespace std;
 using namespace ngraph;
+using json = nlohmann::json;
 
 TEST(serialize, main)
 {

test/util.cpp

@@ -340,3 +340,20 @@ TEST(util, round_up)
     EXPECT_EQ(4, round_up(4, 4));
     EXPECT_EQ(8, round_up(5, 4));
 }
+
+TEST(util, parse_string)
+{
+    EXPECT_FLOAT_EQ(2, parse_string<float>("2"));
+    EXPECT_FLOAT_EQ(2.125, parse_string<float>("2.125"));
+    EXPECT_FLOAT_EQ(numeric_limits<float>::infinity(), parse_string<float>("INFINITY"));
+    EXPECT_FLOAT_EQ(numeric_limits<float>::infinity(), parse_string<float>("infinity"));
+    EXPECT_FLOAT_EQ(-numeric_limits<float>::infinity(), parse_string<float>("-INFINITY"));
+    EXPECT_TRUE(isnan(parse_string<float>("NaN")));
+
+    EXPECT_FLOAT_EQ(2, parse_string<double>("2"));
+    EXPECT_FLOAT_EQ(2.125, parse_string<double>("2.125"));
+    EXPECT_FLOAT_EQ(numeric_limits<double>::infinity(), parse_string<double>("INFINITY"));
+    EXPECT_FLOAT_EQ(numeric_limits<double>::infinity(), parse_string<double>("infinity"));
+    EXPECT_FLOAT_EQ(-numeric_limits<double>::infinity(), parse_string<double>("-INFINITY"));
+    EXPECT_TRUE(isnan(parse_string<double>("NaN")));
+}