Calculations and Number Pitfalls
1234const price = 19.99; const taxRate = 0.07; const total = price + price * taxRate; console.log("Total price with tax:", total);
When you perform calculations in JavaScript, you often use arithmetic operators like +, -, *, and /. These allow you to add, subtract, multiply, and divide numbers to handle tasks such as calculating totals, averages, or percentages. However, JavaScript uses a floating-point number system based on the IEEE 754 standard, which can lead to unexpected results in some real-world calculations.
A common pitfall occurs when working with decimal numbers. For instance, adding 0.1 + 0.2 does not exactly equal 0.3 in JavaScript. Instead, the result is 0.30000000000000004. This happens because some decimal numbers cannot be represented precisely in binary floating-point, leading to tiny rounding errors.
These precision issues can become significant when performing financial calculations, accumulating values over many operations, or comparing numbers for equality. To handle these pitfalls, you can use techniques such as rounding results to a fixed number of decimal places with toFixed() or multiplying values to work with integers instead of floating-point numbers.
Always be aware of these quirks when handling numbers in JavaScript, especially when accuracy is critical.
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Calculations and Number Pitfalls
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1234const price = 19.99; const taxRate = 0.07; const total = price + price * taxRate; console.log("Total price with tax:", total);
When you perform calculations in JavaScript, you often use arithmetic operators like +, -, *, and /. These allow you to add, subtract, multiply, and divide numbers to handle tasks such as calculating totals, averages, or percentages. However, JavaScript uses a floating-point number system based on the IEEE 754 standard, which can lead to unexpected results in some real-world calculations.
A common pitfall occurs when working with decimal numbers. For instance, adding 0.1 + 0.2 does not exactly equal 0.3 in JavaScript. Instead, the result is 0.30000000000000004. This happens because some decimal numbers cannot be represented precisely in binary floating-point, leading to tiny rounding errors.
These precision issues can become significant when performing financial calculations, accumulating values over many operations, or comparing numbers for equality. To handle these pitfalls, you can use techniques such as rounding results to a fixed number of decimal places with toFixed() or multiplying values to work with integers instead of floating-point numbers.
Always be aware of these quirks when handling numbers in JavaScript, especially when accuracy is critical.
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