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Cindy Truong
9,853 PointsWhy am I getting undefined? JavaScript Math Methods
I don't understand how I am getting undefined when I run this. It does the math correctly and shows the number, but 'undefined' is attached to num1 on the browser.
var num1 = prompt("Inuput Number: "); num1 = parseFloat(num1);
var num2 = prompt("Input 2nd number: "); num2 = parseFloat(num2);
var message = document.write("<h1>Math with the numbers " + num1 +" and " + num2 + ":</h1>"); message += num1 + " + " + num2 + " = " + (num1 + num2); document.write(message);
2 Answers
KRIS NIKOLAISEN
54,972 PointsRemove the first document.write when defining message. This is being included by your +=.
var num1 = prompt("Input Number: ");
num1 = parseFloat(num1);
var num2 = prompt("Input 2nd number: ");
num2 = parseFloat(num2);
var message = "<h1>Math with the numbers " + num1 +" and " + num2 + ":</h1>";
message += " " + num1 + " + " + num2 + " = " + (num1 + num2);
document.write(message);
Elijah Quesada
Front End Web Development Techdegree Graduate 32,965 PointsRemove the document.write on line 3 and just leave the very last document.write.
var num1 = prompt("Inuput Number: ");
num1 = parseFloat(num1);
var num2 = prompt("Input 2nd number: ");
num2 = parseFloat(num2);
var message = "<h1>Math with the numbers " + num1 +" and " + num2 + ":</h1>";
message += num1 + " + " + num2 + " = " + (num1 + num2);
document.write(message);
Cindy Truong
9,853 PointsI tried it and it worked perfectly. I should've looked at the code more closely. Thank you!
Elijah Quesada
Front End Web Development Techdegree Graduate 32,965 PointsTo better understand what was happening, try
console.log(document.write("hello"));
and see what you get in the console.