To get the value of pi in php, the easiest way is use the php pi() function. pi() returns the value 3.1415926535898.
echo pi(); // 3.1415926535898
You can also use the php constant M_PI
echo M_PI; // 3.1415926535898
In php, we can easily get the value of pi for use in trigonometry with the php math functions.
For example, let’s say we want to find the sine of a number. The php sin() function takes a number in radians and then finds the sine of the number.
To find the sine of a number, we can use pi to make our lives easy.
To get the value of pi in your php code, you just call the pi() function as shown below.
echo pi(); // 3.1415926535898
Then, if you want to use it like in our example with finding the sine of a number, you can use the pi constant in the following way.
echo sin(pi()/3); // 0.8660254037844386
pi Related Constants You Can Use in php
In php, you can also use the following constants to get the value of pi without using the php pi() function.
These constants are faster than calling the pi() function.
echo M_PI; // 3.14159265358979323846 pi
echo M_PI_2; // 1.57079632679489661923 pi/2
echo M_PI_4; // 0.78539816339744830962 pi/4
echo M_1_PI; // 0.31830988618379067154 1/pi
echo M_2_PI; // 0.63661977236758134308 2/pi
echo M_SQRTPI // 1.77245385090551602729 sqrt(pi)
echo M_2_SQRTPI // 1.12837916709551257390 2/sqrt(pi)
Hopefully this article has been helpful for you to understand how to find the value of pi in php.