feat: Accept input of type number, string & Big

README.md

@@ -15,12 +15,23 @@ Provide a TypeScript implementation for common technical indicators with arbitra
 ## Usage
 
 ```typescript
-import Big from 'big.js';
 import {SMA} from 'trading-signals';
 
 const sma = new SMA(3);
-sma.update(new Big(40));
+
+// You can add numbers:
+sma.update(40);
+sma.update(30);
+sma.update(20);
+
+// You can add strings:
+sma.update('10');
+
+// You can add arbitrary-precision decimals:
+import Big from 'big.js';
 sma.update(new Big(30));
-sma.update(new Big(20));
-console.log(sma.getResult().valueOf()); // "30"
+
+// You can get the result in various formats:
+console.log(sma.getResult().valueOf()); // "20"
+console.log(sma.getResult().toFixed(2)); // "20.00"
 ```

src/EMA/EMA.ts

@@ -1,8 +1,10 @@
-import Big from 'big.js';
+import Big, {BigSource} from 'big.js';
 import {MovingAverage} from '../MA/MovingAverage';
 
 export class EMA extends MovingAverage {
-  update(price: Big): void {
+  update(_price: BigSource): void {
+    const price = new Big(_price);
+
     // If it's the first update there is no previous result and a default has to be set.
     if (!this.result) {
       this.result = price;

src/MA/MovingAverage.ts

@@ -1,4 +1,4 @@
-import Big from 'big.js';
+import Big, {BigSource} from 'big.js';
 
 export abstract class MovingAverage {
   protected result: Big | undefined;
@@ -12,5 +12,5 @@ export abstract class MovingAverage {
     return this.result;
   }
 
-  abstract update(price: Big): void;
+  abstract update(price: BigSource): void;
 }

src/SMA/SMA.ts

@@ -1,11 +1,11 @@
-import Big from 'big.js';
+import Big, {BigSource} from 'big.js';
 import {MovingAverage} from '../MA/MovingAverage';
 
 export class SMA extends MovingAverage {
   private readonly prices: Big[] = [];
 
-  update(price: Big): void {
-    this.prices.push(price);
+  update(price: BigSource): void {
+    this.prices.push(new Big(price));
 
     if (this.prices.length > this.interval) {
       this.prices.shift();

src/SMMA/SMMA.ts

@@ -1,4 +1,4 @@
-import Big from 'big.js';
+import Big, {BigSource} from 'big.js';
 import {SMA} from '../';
 
 class SMMA {
@@ -14,8 +14,8 @@ class SMMA {
     this.result = new Big(0);
   }
 
-  update(price: Big): void {
-    this.prices.push(price);
+  update(price: BigSource): void {
+    this.prices.push(new Big(price));
 
     if (this.prices.length < this.interval) {
       this.sma.update(price);