X-Git-Url: http://git.scottworley.com/inverse-tax/blobdiff_plain/9737900ee57988ffb64fea66f4c6e4245d51ad9a..1c6e40691d86539d80018aa8fc495272b900c4c4:/tax.js

diff --git a/tax.js b/tax.js
index 0d94200..d26db5f 100644
--- a/tax.js
+++ b/tax.js
@@ -49,6 +49,8 @@ function merge_tax_tables(t1, t2) {
 }
 
 function invert(table) {
+  if (table.length == 0) return x => x;
+
   // Here we solve
   //   net = m * gross + b
   // for gross: