Expand example

Author: mborland

examples/fmt_format.cpp

@@ -3,19 +3,37 @@
 // https://www.boost.org/LICENSE_1_0.txt
 
 #include <boost/decimal.hpp>
+#include <boost/decimal/fmt_format.hpp>
 #include <iostream>
 
 #if defined(BOOST_DECIMAL_HAS_FMTLIB_SUPPORT) && defined(BOOST_DECIMAL_TEST_FMT)
 
-#include <boost/decimal/fmt_format.hpp>
-
 int main()
 {
     constexpr boost::decimal::decimal64_t val1 {314, -2};
     constexpr boost::decimal::decimal32_t val2 {3141, -3};
 
+    // The easiest is no specification which is general format
+    // Given these values they will print in fixed format
+    std::cout << "Default Format:\n";
+    std::cout << fmt::format("{}", val1) << '\n';
+    std::cout << fmt::format("{}", val2) << "\n\n";
+
+    // Next we can add a type modifier to get scientific formatting
+    std::cout << "Scientific Format:\n";
+    std::cout << fmt::format("{:e}", val1) << '\n';
+    std::cout << fmt::format("{:e}", val2) << "\n\n";
+
+    // Next we can add a type modifier to get scientific formatting
+    // Here this gives one digit of precision rounded according to current rounding mode
+    std::cout << "Scientific Format with Specified Precision:\n";
+    std::cout << fmt::format("{:.1e}", val1) << '\n';
+    std::cout << fmt::format("{:.1e}", val2) << "\n\n";
+
+    // This combines the padding modifier (10), precision (3 digits), and a type modifier (e)
+    std::cout << "Scientific Format with Specified Precision and Padding:\n";
     std::cout << fmt::format("{:10.3e}", val1) << '\n';
-    std::cout << fmt::format("{:10.3e}", val2) << std::endl;
+    std::cout << fmt::format("{:10.3e}", val2) << '\n';
 
     return 0;
 }