feat(calculator.ts): add inverse method

gfmio · Mar 7, 2019 · 0ed8578 · 0ed8578
1 parent f5d30cb
commit 0ed8578
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diff --git a/src/Calculator.ts b/src/Calculator.ts
@@ -71,4 +71,9 @@ export default class Calculator {
     this.current = Math.tan(this.current);
     return this;
   }
+
+  public inverse() {
+    this.current = div(1, this.current);
+    return this;
+  }
 }
diff --git a/tests/Calculator.test.ts b/tests/Calculator.test.ts
@@ -22,4 +22,6 @@ describe("Calculator", () => {
   it("can cos", () => expect(calculator.cos().value()).equal(1));
   // prettier-ignore
   it("can tan", () => expect(calculator.clear().tan().value()).equal(0));
+  // prettier-ignore
+  it("can invert", () => expect(calculator.clear().add(2).inverse().value()).equal(1 / 2));
 });