# Fortran/Fortran Simple math

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< Fortran

*Part of the Fortran WikiBook*

Fortran has the following arithmetic operators:

**+**addition**-**subtraction*****multiplication**/**division******exponentiation (associates right-to-left)

Here are some examples of their use:

i = 2 + 3 ! sets i equal to 5 i = 2 * 3 ! sets i equal to 6 i = 2 / 3 ! sets i equal to 0, since 2/3 is rounded down to the integer 0, see mixed mode x = 2 / 3.0 ! sets x approximately equal to 2/3 or 0.666667 i = 2 ** 3 ! sets i equal to 2*2*2 = 8

Fortran has a wide range of functions useful in numerical work, such as **sin**, **exp**, and **log**. The argument of a function must have the proper type, and it is enclosed in parentheses:

x = sin(3.14159) ! sets x equal to sin(pi), which is zero

The intrinsic math functions of Fortran are **elemental**, meaning that they can take arrays as well as scalars as arguments and return a scalar or an array of the same shape:

real :: x(2),pi=3.14159 x = sin((/pi,pi/2/))

The above program fragment sets the two elements of array x, x(1) and x(2), equal to sin(pi) and sin(pi/2) respectively.