


Why Does PHP Display Small Decimals in Scientific Notation (e.g., .000021 as 2.1E-5)?
Dec 11, 2024 am 03:12 AMScientific Notation in PHP: Understanding .000021 Output
In PHP, you may encounter situations where numbers specified in decimals are printed in scientific notation, which can be confusing. This can occur even when the decimal is a small value, such as .000021, which should logically print as-is.
Why Scientific Notation?
PHP interprets small decimals as very large numbers with exponents of -10. In this case, .000021 is internally represented as 2.1 x 10^-5. To maintain precision, PHP prints it in scientific notation as 2.1E-5.
Solution using number_format()
To print the number as intended (.000021), you can use the number_format() function. It allows you to specify the number of decimal places to display:
$var = .000021; echo number_format($var, 5); // Output: 0.000021
Alternatively with sprintf()
You can also use the sprintf() function to control formatting:
$var = .000021; printf("%.5f", $var); // Output: 0.000021
Using either of these methods will ensure that your numbers are displayed in the desired format, without resorting to scientific notation.
The above is the detailed content of Why Does PHP Display Small Decimals in Scientific Notation (e.g., .000021 as 2.1E-5)?. For more information, please follow other related articles on the PHP Chinese website!

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