Data commit

Task/Temperature-conversion/D/temperature-conversion.d

@@ -0,0 +1,33 @@
+double kelvinToCelsius(in double k) pure nothrow @safe {
+    return k - 273.15;
+}
+
+double kelvinToFahrenheit(in double k) pure nothrow @safe {
+    return k * 1.8 - 459.67;
+}
+
+double kelvinToRankine(in double k) pure nothrow @safe {
+    return k * 1.8;
+}
+
+unittest {
+    import std.math: approxEqual;
+    assert(approxEqual(kelvinToCelsius(21.0), -252.15));
+    assert(approxEqual(kelvinToFahrenheit(21.0), -421.87));
+    assert(approxEqual(kelvinToRankine(21.0), 37.8));
+}
+
+void main(string[] args) {
+    import std.stdio, std.conv, std.string;
+
+    if (args.length == 2 && isNumeric(args[1])) {
+        immutable kelvin = to!double(args[1]);
+        if (kelvin >= 0) {
+            writefln("K  %2.2f", kelvin);
+            writefln("C  %2.2f", kelvinToCelsius(kelvin));
+            writefln("F  %2.2f", kelvinToFahrenheit(kelvin));
+            writefln("R  %2.2f", kelvinToRankine(kelvin));
+        } else
+            writefln("%2.2f K is below absolute zero", kelvin);
+    }
+}