2016 Update

Task/Sparkline-in-unicode/JavaScript/sparkline-in-unicode.js

@@ -0,0 +1,49 @@
+(() => {
+    'use strict';
+
+    // sparkLine :: [Num] -> String
+    let sparkLine = xs => {
+            let min = minimumBy(numericOrdering, xs),
+                max = maximumBy(numericOrdering, xs),
+                range = max - min;
+
+            return xs.map(x => ((x - min) * 7) / range)
+                .map(
+                    n => (n >= 0 && n < 8) ? '▁▂▃▄▅▆▇█'
+                    .split('')[Math.round(n)] : undefined
+                ).join('');
+        },
+
+        // maximumBy :: (a -> a -> Ordering) -> [a] -> a
+        maximumBy = (f, xs) =>
+            xs.reduce((a, x) =>
+                a === undefined ? x : (
+                    f(x, a) > 0 ? x : a
+                ),
+                undefined
+            ),
+
+
+        // minimumBy :: (a -> a -> Ordering) -> [a] -> a
+        minimumBy = (f, xs) =>
+            xs.reduce((a, x) =>
+                a === undefined ? x : (
+                    f(x, a) < 0 ? x : a
+                ),
+                undefined
+            ),
+
+        numericOrdering = (a, b) => a < b ? -1 : (a > b ? 1 : 0);
+
+    // TEST
+
+    return ["1 2 3 4 5 6 7 8 7 6 5 4 3 2 1",
+        "1.5, 0.5 3.5, 2.5 5.5, 4.5 7.5, 6.5",
+        "3 2 1 0 -1 -2 -3 -4 -3 -2 -1 0 1 2 3",
+        "-1000 100 1000 500 200 -400 -700 621 -189 3"
+    ].map(
+        s => s.split(/[,\s]+/)
+        .map(x => parseFloat(x, 10))
+    ).map(sparkLine);
+
+})();