4 files changed, 34 insertions, 0 deletions
diff --git a/node_modules/es5-ext/math/atanh/implement.js b/node_modules/es5-ext/math/atanh/implement.js
new file mode 100644
index 000000000..47d5cc22a
--- /dev/null
+++ b/node_modules/es5-ext/math/atanh/implement.js
@@ -0,0 +1,8 @@
+"use strict";
+
+if (!require("./is-implemented")()) {
+	Object.defineProperty(Math, "atanh", { value: require("./shim"),
+		configurable: true,
+enumerable: false,
+writable: true });
+}
diff --git a/node_modules/es5-ext/math/atanh/index.js b/node_modules/es5-ext/math/atanh/index.js
new file mode 100644
index 000000000..51fbcd66a
--- /dev/null
+++ b/node_modules/es5-ext/math/atanh/index.js
@@ -0,0 +1,5 @@
+"use strict";
+
+module.exports = require("./is-implemented")()
+	? Math.atanh
+	: require("./shim");
diff --git a/node_modules/es5-ext/math/atanh/is-implemented.js b/node_modules/es5-ext/math/atanh/is-implemented.js
new file mode 100644
index 000000000..4787c4fa6
--- /dev/null
+++ b/node_modules/es5-ext/math/atanh/is-implemented.js
@@ -0,0 +1,7 @@
+"use strict";
+
+module.exports = function () {
+	var atanh = Math.atanh;
+	if (typeof atanh !== "function") return false;
+	return Math.round(atanh(0.5) * 1e15) === 549306144334055;
+};
diff --git a/node_modules/es5-ext/math/atanh/shim.js b/node_modules/es5-ext/math/atanh/shim.js
new file mode 100644
index 000000000..9383e9714
--- /dev/null
+++ b/node_modules/es5-ext/math/atanh/shim.js
@@ -0,0 +1,14 @@
+"use strict";
+
+var log = Math.log;
+
+module.exports = function (value) {
+	if (isNaN(value)) return NaN;
+	value = Number(value);
+	if (value < -1) return NaN;
+	if (value > 1) return NaN;
+	if (value === -1) return -Infinity;
+	if (value === 1) return Infinity;
+	if (value === 0) return value;
+	return 0.5 * log((1 + value) / (1 - value));
+};