all tasks

Task/Temperature-conversion/PHP/temperature-conversion.php

@@ -0,0 +1,20 @@
+error_reporting(E_ALL & ~ ( E_NOTICE | E_WARNING ));
+
+while (true) {
+    echo "\nEnter a value in kelvin (q to quit): ";
+    if (($kelvin = trim(fgets(STDIN))) !== false) {
+        if ($kelvin == 'q') {
+            echo 'quitting';
+            break;
+        }
+        if (is_numeric($kelvin)) {
+            $kelvin = floatVal($kelvin);
+            if ($kelvin >= 0) {
+                printf(" K  %2.2f\n", $kelvin);
+                printf(" C  %2.2f\n", $kelvin - 273.15);
+                printf(" F  %2.2f\n", $kelvin * 1.8 - 459.67);
+                printf(" R  %2.2f\n", $kelvin * 1.8);
+            } else printf(" %2.2f K is below absolute zero\n", $kelvin);
+        }
+    }
+}