add protein

1 files changed, 10 insertions, 0 deletions

diff --git a/src/protein/protein.js b/src/protein/protein.js
new file mode 100644
index 0000000..0223203
--- /dev/null
+++ b/src/protein/protein.js
@@ -0,0 +1,10 @@
+const xnor = (a, b) => a === b ? 1 : 0;
+
+export function compare(pa, pb) {
+	if (pa.length !== pb.length) {
+		throw new Error(`attempted to compare proteins with different lengths: ${pa.length} vs ${pb.length}`);
+	}
+	return (1/pa.length) * pa
+		.map((_, i) => xnor(pa[i], pb[i]))
+		.reduce((acc, val) => acc + val, 0)
+}