This article mainly introduces how the round () function in PHP rounds floating-point numbers. it summarizes various common usage of the round () function through detailed examples, it is a very practical technique. if you need it, you can refer to the following example to describe how the round () function in PHP rounds the floating point number. Share it with you for your reference. The specific method is as follows:
Syntax: round (x, prec)
Parameters |
Description |
X |
(Optional) number to be rounded. |
Prec |
(Optional) number of digits after the decimal point. |
Note: the result of rounding x to the specified precision prec (number of digits after decimal point) is returned. The prec value can also be a negative number or zero (default value ).
Tips and comments
Note: php cannot properly process strings similar to "12,300.2" by default.
Note: The prec parameter is introduced in php 4. the instance code is as follows:
The code is as follows:
<? Php
*/
Echo round (3.4); // output 3
Echo"
";
Echo round (3.5); // output 4
Echo"
";
Echo round (3.6); // output 4
Echo"
";
Echo round (3.6, 0); // output 4
Echo"
";
Echo round (1.95583, 2); // output 1.96
Echo"
";
Echo round (1241757,-3); // output 1242000
Echo"
";
Echo round (4.045, 2); // output 4.05
Echo"
";
Echo round (4.055, 2); // output 4.06
// Use the stdround function instead of the php round function
?>
The code is as follows:
<? Php
Function stdround ($ num, $ d = 0)
{
Return round ($ num + 0.0001/pow (10, $ d), $ d );
}
Echo "round (1.005, 2) =". round (1.005, 2). "n ";
Echo "round (1.015, 2) =". round (1.015, 2). "n ";
Echo "round (1.025, 2) =". round (1.025, 2). "n ";
Echo "round (1.035, 2) =". round (1.035, 2). "n ";
Echo "round (1.045, 2) =". round (1.045, 2). "n ";
Echo "round (1.055, 2) =". round (1.055, 2). "n ";
Echo "round (1.065, 2) =". round (1.065, 2). "n ";
Echo "round (1.075, 2) =". round (1.075, 2). "n ";
Echo "round (1.085, 2) =". round (1.085, 2). "n ";
Echo "round (1.095, 2) =". round (1.095, 2). "n ";
Echo "stdround (1.005, 2) =". stdround (1.005, 2). "n ";
Echo "stdround (1.015, 2) =". stdround (1.015, 2). "n ";
Echo "stdround (1.025, 2) =". stdround (1.025, 2). "n ";
Echo "stdround (1.035, 2) =". stdround (1.035, 2). "n ";
Echo "stdround (1.045, 2) =". stdround (1.045, 2). "n ";
Echo "stdround (1.055, 2) =". stdround (1.055, 2). "n ";
Echo "stdround (1.065, 2) =". stdround (1.065, 2). "n ";
Echo "stdround (1.075, 2) =". stdround (1.075, 2). "n ";
Echo "stdround (1.085, 2) =". stdround (1.085, 2). "n ";
Echo "stdround (1.095, 2) =". stdround (1.095, 2). "n ";
$ M = 0.000000000000001;
Echo "n ";
Echo "round (1.005 + {$ m}, 2) =". round (1.005 + $ m, 2). "n ";
Echo "round (1.015 + {$ m}, 2) =". round (1.015 + $ m, 2). "n ";
Echo "round (1.025 + {$ m}, 2) =". round (1.025 + $ m, 2). "n ";
Echo "round (1.035 + {$ m}, 2) =". round (1.035 + $ m, 2). "n ";
Echo "round (1.045 + {$ m}, 2) =". round (1.045 + $ m, 2). "n ";
Echo "round (1.055 + {$ m}, 2) =". round (1.055 + $ m, 2). "n ";
Echo "round (1.065 + {$ m}, 2) =". round (1.065 + $ m, 2). "n ";
Echo "round (1.075 + {$ m}, 2) =". round (1.075 + $ m, 2). "n ";
Echo "round (1.085 + {$ m}, 2) =". round (1.085 + $ m, 2). "n ";
Echo "round (1.095 + {$ m}, 2) =". round (1.095 + $ m, 2). "n ";
Echo "round (1.005, 2) =". round (1.005, 2). "n ";
Echo "round (1.015, 2) =". round (1.015, 2). "n ";
Echo "round (1.025, 2) =". round (1.025, 2). "n ";
Echo "round (1.035, 2) =". round (1.035, 2). "n ";
Echo "round (1.045, 2) =". round (1.045, 2). "n ";
Echo "round (1.055, 2) =". round (1.055, 2). "n ";
Echo "round (1.065, 2) =". round (1.065, 2). "n ";
Echo "round (1.075, 2) =". round (1.075, 2). "n ";
Echo "round (1.085, 2) =". round (1.085, 2). "n ";
Echo "round (1.095, 2) =". round (1.095, 2). "n ";
?>
I hope this article will help you with PHP programming.