Added trailing 0s for divide by 0 with precision

should close issue #57

src/divide.spec.ts

@@ -100,4 +100,7 @@ describe("divide", function () {
   it(".102 / .0383292 = 2.66115651", function () {
     expect(divide(".102", ".0383292", 8)).toBe("2.66115651");
   });
+  it("divide(0, 2, 3) should add trailing 0s", function () {
+    expect(divide(0, 2, 3)).toBe("0.000");
+  });
 });

src/divide.ts

@@ -1,21 +1,27 @@
 import { add, trim } from './add';
 import { roundOff } from './round';
 
-export function divide(dividend, divisor, precission = 8) {
-    if (divisor == 0) {
-        throw new Error('Cannot divide by 0');
+export function divide(dividend: string | number, divisor: string | number, precission?:number) {
+    // Convert to string
+    if (typeof dividend == 'number' || typeof divisor == 'number') {
+        dividend = dividend.toString();
+        divisor = divisor.toString();
     }
 
-    dividend = dividend.toString();
-    divisor = divisor.toString();
+    // Return 0 
+    if (divisor == '0') {
+        return '0' + (!precission)? '': '.' + new Array(precission).join('0');
+    }
+
+    // Set default precission
+    if(typeof precission == 'undefined'){
+        precission = 8;
+    }
 
     // remove trailing zeros in decimal ISSUE#18
     dividend = dividend.replace(/(\.\d*?[1-9])0+$/g, "$1").replace(/\.0+$/, "");
     divisor = divisor.replace(/(\.\d*?[1-9])0+$/g, "$1").replace(/\.0+$/, "");
 
-    if (dividend == 0)
-        return '0';
-
     let neg = 0;
     if (divisor[0] == '-') {
         divisor = divisor.substring(1);
@@ -51,7 +57,7 @@ export function divide(dividend, divisor, precission = 8) {
     let prec = 0, dl = divisor.length, rem = '0', quotent = '';
     let dvnd = (dividend.indexOf('.') > -1 && dividend.indexOf('.') < dl) ? dividend.substring(0, dl + 1) : dividend.substring(0, dl);
     dividend = (dividend.indexOf('.') > -1 && dividend.indexOf('.') < dl) ? dividend.substring(dl + 1) : dividend.substring(dl);
-    
+
     if (dvnd.indexOf('.') > -1) {
         let shift = dvnd.length - dvnd.indexOf('.') - 1;
         dvnd = dvnd.replace('.', '');

src/pow.ts

@@ -1,5 +1,5 @@
 import { abs } from "./abs";
-import { compareTo, greaterThan, isNotZero, isOne, lessThan } from "./compareTo";
+import { compareTo, greaterThan, isNotZero, isOne, isZero, lessThan } from "./compareTo";
 import { divide } from "./divide";
 import { modulus } from "./modulus";
 import { multiply } from "./multiply";
@@ -55,6 +55,18 @@ export function pow(base: number | string, exponent: number | string, percision:
     exponent = exponent.toString();
     base = base.toString();
 
+    if(isZero(exponent)){
+        return '1'
+    }
+
+    if(!exponent.includes('-') && isOne(exponent)){
+        return base
+    }
+
+    if(isZero(base) && exponent.includes('-') && isOne(exponent)){
+        throw Error('0^(-1) is undefined');
+    }
+
     const remainder = abs(modulus(exponent));
     const reciprical = exponent.includes('-');
     const negativeBase = base.includes('-');