I'm trying to print to screen this times table in reverse like the photo but can't figure what I need to change to do that.
var digit = 9, multiplier = 9, textresult = "", result = 0;
while (digit > 0) {
for (multiplier = 9; multiplier >= digit; multiplier--) {
result = digit * multiplier;
if (digit == multiplier) {
textresult += digit + " x " + multiplier + " = " + result + "
<br>";}
else {
textresult += digit + " x " + multiplier + " = " + result +
" ";}
}
digit--;}
strong textdocument.write(textresult);
any Ideas?
Try this correction
var digit = 1,
textresult = "<pre><code>",
max = 9;
while (digit <= max) {
for (var multiplier = digit; multiplier <= max; multiplier++) {
var result = digit * multiplier;
textresult += digit + " * " + multiplier + " = " + result;
if (10 > result) {
textresult += " ";
}
if (max == multiplier) {
textresult += "<br/>";
} else {
textresult += " ";
}
}
digit++;
}
textresult += "</pre></code>";
document.write(textresult);
Count from digit of 1 up, rather than from 9 down. On each inner loop, initialize multiplier to digit instead of 9, and similarly, count up with multiplier:
var digit = 1,
textresult = "";
while (digit < 10) {
for (let multiplier = digit; multiplier < 10; multiplier++) {
const result = digit * multiplier;
textresult += digit + " x " + multiplier + " = " + result + (multiplier === 9 ? '<br>' : " ");
}
digit++;
}
document.write(textresult);
Related
I need my code to only accept whole numbers, no decimals and should prompt an error when a decimal gets entered. I don't want a new function , I'm hoping I can just add lines to my function but I don't know what I need to add.
function number_function() {
number = parseInt(prompt('Enter a positive integer:'));
if (number < 0) {
alert('Error! Factorial for negative number does not exist. But I will show you the positive number');
number = number * -1;
let n = 1;
for (i = 1; i <= number; i++) {
n *= i;
}
alert("The factorial of " + number + " is " + n + ".");
} else if (number === 0) {
alert("Please enter a number greater than 0");
} else {
let n = 1;
for (i = 1; i <= number; i++) {
n *= i;
}
alert("The factorial of " + number + " is " + n + ".");
}
}
number_function();
You can do this to check if the number has decimals
const val = 10.7 % 1;
if (val !== 0) {
console.log('has decimals');
} else {
console.log('has no decimal');
}
JavaScript provides the built-in function Number.isInteger(n)
So I'm fairly new to JavaScript but I cannot seem to find the average in my code. I want to understand why my average is not working. Any help you guys?
function getEvenOdd() {
var oddSum = 0;
var evenSum = 0;
var num = 0;
var evenAvg = 0;
var oddAvg = 0;
while (true) {
num = parseInt(prompt("Enter a number(-1 to exit)"));
if (num == -1) {
break;
}
if (num % 2 == 0) {
evenSum += num;
} else {
oddSum += num;
}
evenAvg = evenSum / num;
oddAvg = oddSum / num;
}
alert("Sum of all even numbers is: " + evenSum);
alert("Sum of all odd numbers is: " + oddSum);
alert("Average of all even numbers is : " + evenAvg);
alert("Average of all odd numbers is: " + oddAvg);
}
On your code, to calculate the oddAvg and evenAvg, you have divided evenSum and oddSum by num variable (which is input from prompt).
And as you know, average = total sum / total count, so it's not right to divide the sum by the input number variable.
Instead of that, you need to calculate the count of odd and even numbers and divide the even and odd sum by the even and odd number counts as follows.
function getEvenOdd() {
var oddSum = 0;
var evenSum = 0;
var num = 0;
var evenAvg = 0;
var oddAvg = 0;
var evenCount = 0;
var oddCount = 0;
while (true) {
num = parseInt(prompt("Enter a number(-1 to exit)"));
if (num == -1) {
break;
}
if (num % 2 == 0) {
evenSum += num;
evenCount ++;
} else {
oddSum += num;
oddCount ++;
}
}
evenAvg = evenSum / evenCount;
oddAvg = oddSum / oddCount;
alert("Sum of all even numbers is: " + evenSum);
alert("Sum of all odd numbers is: " + oddSum);
alert("Average of all even numbers is : " + evenAvg);
alert("Average of all odd numbers is: " + oddAvg);
}
getEvenOdd();
These operations are dividing the evenSum or oddSum by the last input num.
evenAvg = evenSum / num;
oddAvg = oddSum / num;
You should divide the sum by the number of even or odd inputs.
Instead of evenSum / num use evenSum/Count of Numbers entered.
How about this solution? It is aiming to store odd and even numbers into oddList and evenList.
function getEvenOdd() {
var evenAvg = 0;
var oddAvg = 0;
var oddList = [];
var evenList = [];
var num = 0;
while (true) {
num = parseInt(prompt("Enter a number(-1 to exit)"));
if (num == -1) {
break;
}
if (num % 2 == 0) {
evenList.push(parseInt(num));
} else {
oddList.push(parseInt(num));
}
evenAvg = evenList.reduce((p, c) => p + c, 0) / evenList.length;
oddAvg = oddList.reduce((p, c) => p + c, 0) / oddList.length;
}
alert("Sum of all even numbers is: " + evenList.length);
alert("Sum of all odd numbers is: " + oddList.length);
alert("Average of all even numbers is : " + evenAvg);
alert("Average of all odd numbers is: " + oddAvg);
}
getEvenOdd();
function NumStuff(num) {
this.num = num;
this.multipleOfFour = function() {
//if multiple of 4
if (this.num % 4 === 0) {
console.log(this.num + " is a multiple of Four");
console.log("the structure of the given integer " +
this.num + " is ");
for (let i = 0; i < this.num; i++) {
if (4 * i === this.num) { //why is this.num outside of
//lexical scope
console.log(this.num + " = " + i + " x 4");
break;
}
}
//if not a multiple of 4
} else {
console.log(this.num + " isn't a multiple of 4 but here is the integer's structure:");
let remainder = this.num % 4;
let tempNum = this.num - remainder;
for (let i = 0; i < tempNum; i++) {
if (4 * i === tempNum) {
console.log(this.num + " = " + i + " x 4 + " + remainder);
break;
}
}
}
};
}
let num = prompt("Enter an integer:");
let n = new NumStuff(num);
n.multipleOfFour();
Say we enter 20 as our num. It passes through the multipleOfFour() and hits the first if conditional. This.num(20) % 4 is equal to 0 so it passes.Then we loop through i to find what number times 4 is equal to 20. This.num is in the scope of the for statement but not in the scope of the inner if conditional of the for statement. Why is that so?
It is in the scope. That's not the issue.
But this.num is a string (that's what prompt always returns) while 4 * i is a number. And 4 * i === this.num will always be false, regardless of what you enter when prompted.
Try this (here):
for (let i = 0; i < this.num; i++) {
console.log('x', 4 * i, this.num, 4 * i === this.num);
An easy fix is let num = parseInt(prompt("Enter an integer:"));.
I am trying to complete a multiplication table but am running into an issue, this is my code...
function multiTable(number) {
var table = '';
for (i = 1; i < 11; i++) {
if (i == 1 || number == 2 || number == 3 || number == 4 || number == 5 || number == 6 || number == 7 || number == 8 || number == 9) {
table += i + " * " + number + " = " + (i * number) + "\n";
} else if (i = 10) {
table += i + " * " + number + " = " + (i * number);
}
}
return table;
}
When I put it through the tests provided I get ...
'1 * 5 = 5\n2 * 5 = 10\n3 * 5 = 15\n4 * 5 = 20\n5 * 5 = 25\n6 * 5 = 30\n7 * 5 = 35\n8 * 5 = 40\n9 * 5 = 45\n10 * 5 = 50\n'
I am supposed to get ...
'1 * 5 = 5\n2 * 5 = 10\n3 * 5 = 15\n4 * 5 = 20\n5 * 5 = 25\n6 * 5 = 30\n7 * 5 = 35\n8 * 5 = 40\n9 * 5 = 45\n10 * 5 = 50'
To save anyone some time the only difference is the very end, the \n after 50.
I don't know if this will help but this is the test:
Test.describe("Basic tests",() => {
Test.assertEquals(multiTable(5), '1 * 5 = 5\n2 * 5 = 10\n3 * 5 = 15\n4 * 5 = 20\n5 * 5 = 25\n6 * 5 = 30\n7 * 5 = 35\n8 * 5 = 40\n9 * 5 = 45\n10 * 5 = 50');
})
function multiTable(number) {
var table = '';
for(var i = 1; i < 10; i += 1){ // print 9 times with \n
table += i + " * " + number + " = " + (i * number) + "\n";
}
table += 10 + " * " + number + " = " + (10 * number); // and last line
return table;
}
console.log(multiTable(5));
.as-console-wrapper { max-height: 100% !important; top: 0; }
i figured out the solution here it is
function multiTable(number) {
var table = '';
for(i=1;i<11;i++){
if(i === 10){
table += i+ " * " +number+ " = " +(i*number);
}else{
table += i+ " * " +number+ " = " +(i*number)+ "\n";
}
}
return table;
}
I am writing a program to display total test grades and avg with a loop. however when I try to test it, I cant get the final message "Good Job" to show up and I am getting a error for unbalanced tree and undefined "Avg" variable. I dont see how "avg" is undefined when it works during the loop just not after
var Testscore = 0;
var Testcount = 0;
var Total = 0;
var Avg = 0;
do {
Testscore = prompt("Enter the test score ", 0);
Testcount = (Testcount + 1);
Total = parseFloat(Testscore) + parseFloat(Total);
Avg = (Total / Testcount);
document.write("Total test score is " + Total + "<br>");
document.write("Average test score is " + Avg + "<br>" + "<br>");
} while (Testcount < 4)
Avg = (Total / Testcount);
if (avg > 80) {
document.write("Good Job!");
} else {
documet.write("Try harder..");
}
You just had a few typos in your code!
avg and Avg are different, as variables are case sensitive.
Additionally, there's a documet instead of document
var Testscore = 0;
var Testcount = 0;
var Total = 0;
var Avg = 0;
do
{
Testscore = prompt("Enter the test score ",0);
Testcount = (Testcount + 1);
Total = parseFloat(Testscore) + parseFloat(Total);
Avg = (Total / Testcount);
document.write("Total test score is " + Total + "<br>");
document.write("Average test score is " + Avg + "<br>" + "<br>");
} while (Testcount < 4)
Avg = (Total / Testcount);
if (Avg > 80)
{
console.log("Good Job!");
}
else
{
console.log("Try harder..");
}