A simple calculator for basic operations. Enter two numbers and select an operation.
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–
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Understanding the Big Button Calculator
The "Big Button Calculator" is a straightforward tool designed for fundamental arithmetic operations. It allows users to input two numerical values and select one of four basic mathematical operations: addition, subtraction, multiplication, or division.
How it Works:
The calculator operates on the principle of taking two operands (the input values) and applying a chosen operator to derive a single result. The logic is as follows:
Input Values: Users provide two numbers, referred to as number1 and number2. These can be integers or decimal numbers.
Operation Selection: Users select the desired arithmetic operation from a dropdown menu:
Addition (+):number1 + number2
Subtraction (-):number1 - number2
Multiplication (*):number1 * number2
Division (/):number1 / number2
Calculation: Upon clicking the "Calculate" button, the JavaScript code retrieves the input values and the selected operation. It then performs the corresponding calculation.
Error Handling: Crucially, the calculator includes checks to ensure valid numerical inputs are provided. It also specifically handles division by zero, which is an undefined mathematical operation, to prevent errors and inform the user.
Mathematical Operations:
The calculator performs the following standard arithmetic operations:
Addition: Combines two numbers to find their sum.
Subtraction: Finds the difference between two numbers.
Multiplication: Calculates the product of two numbers.
Division: Splits one number by another to find the quotient. Special attention is given to the case where the divisor (number2) is zero.
Educational purposes for understanding fundamental arithmetic.
As a foundational example for building more complex calculators.
The "Big Button" design emphasizes ease of use, especially on touch devices, making basic calculations accessible with minimal effort.
function calculateBigButton() {
var num1 = parseFloat(document.getElementById("number1").value);
var num2 = parseFloat(document.getElementById("number2").value);
var operation = document.getElementById("operation").value;
var resultDiv = document.getElementById("result");
resultDiv.textContent = "; // Clear previous result
// Input validation
if (isNaN(num1) || isNaN(num2)) {
resultDiv.textContent = "Error: Please enter valid numbers.";
resultDiv.style.backgroundColor = "#dc3545"; // Error color
return;
}
var result;
switch (operation) {
case "add":
result = num1 + num2;
break;
case "subtract":
result = num1 – num2;
break;
case "multiply":
result = num1 * num2;
break;
case "divide":
if (num2 === 0) {
resultDiv.textContent = "Error: Cannot divide by zero.";
resultDiv.style.backgroundColor = "#dc3545"; // Error color
return;
}
result = num1 / num2;
break;
default:
resultDiv.textContent = "Error: Invalid operation selected.";
resultDiv.style.backgroundColor = "#dc3545"; // Error color
return;
}
// Display result
// Format result to avoid excessive decimals if it's a whole number
if (Number.isInteger(result)) {
resultDiv.textContent = result;
} else {
resultDiv.textContent = result.toFixed(4); // Display up to 4 decimal places
}
resultDiv.style.backgroundColor = "var(–success-green)"; // Reset to success color
}