php set to long integer type

PHP is a general-purpose high-level programming language that is widely used in web development. PHP has a default setting that integer types are 32-bit signed integers. This means that the largest integer that can be represented is 2^31-1, which is 2147483647. If you need to handle large numbers, such as very large integers or integers exceeding 32 bits, then you need to set the integer type in PHP to long integer type.

Why do you need to set PHP to long integer type?

PHP's default integer type may not meet some needs. For example, when you need to perform calculations on large numbers, PHP's default integer type may return incorrect calculation results. This is because PHP's default integer type can only represent a maximum of 32-bit signed integers. If the result of your calculation exceeds this range, overflow will occur, resulting in incorrect calculation results.

The long integer type allows you to perform large number calculations and integer calculations exceeding 32 bits without overflow errors. When the PHP integer type is set to long, you can use new mathematical functions such as the GMP function to perform large number calculations.

How to set PHP to long integer type?

To set PHP to long integer type, you need to make changes in the php.ini file. First, you need to find the location of the php.ini file. On Unix/Linux systems, this file is usually located in /etc/php.ini or /etc/php5.ini. In Windows systems, the php.ini file can be found in the PHP installation directory. After opening the php.ini file, you need to search for the following line:

; Default value: On
; Development value: Off
; Production value: Off
 
; http://php.net/precision
precision = 14

This line allows you to set the precision of floating point numbers. You need to set the "precision" parameter to -1 so that PHP can be set to long integer type. The first modified line should look like this:

; Default value: On
; Development value: Off
; Production value: Off
 
; http://php.net/precision
precision = -1

After completing the modification, you need to restart the PHP interpreter to ensure that the changes take effect.

You may ask, why do you need to set the float precision parameter to -1 to set PHP to long integer type? This is because if you set the precision to 0, any floating point calculations will be disabled, although this is not your original purpose. On the other hand, if you set the precision to 1, it will set PHP to a short integer type.

Things to note

Please note that after setting the integer type to a long integer type in PHP, all integer calculations will use the long integer type. This will result in slower calculations, especially when dealing with large numbers. If your application only needs to handle a small number of large number calculations, it is best not to set PHP to the long integer type.

Additionally, after setting PHP to the long integer type, you will also need to use the GMP function in PHP to perform large number calculations. These functions can be found in PHP's official documentation and provide a common interface for performing high-precision calculations.

Conclusion

Setting PHP's integer type to a long integer type can solve the problem of large number calculations and integer calculations exceeding 32 bits. Although this may make calculations slower, it is a must if you need to deal with large numbers. Setting PHP's long integer type is very simple. Just set the floating point precision to -1 in the php.ini file. But be aware that all integer calculations will be in long integer types, and you will need to use GMP functions to perform large number calculations.

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