FORTRAN 90
Lecture : Rafel Hekmat Hameed
University of Babylon
Subject : Fortran 90
College of Engineering
Year : Second B.Sc
Mechanical Engineering Dep.
1. INTRINSIC FUNCTIONS
 MATHEMATICAL FUNCTIONS
Function
ABS(x)
SQRT(x)
SIN(x)
COS(x)
TAN(x)
ASIN(x)
ACOS(x)
ATAN(x
SINH(x)
COSH(x)
TANH(x)
EXP(x)
LOG(x)
LOG10(x)
Meaning
absolute value of x
square root of x
sine of x radian
cosine of x radian
tangent of x radian
arc sine of x
arc cosine of x
arc tangent of x
hyperbolic sine of x
hyperbolic cosine of x
hyperbolic tangent of x
exp(x)
natural logarithm of x
Log10 base of 10 logarithm of x
 SOME cONVERSION FUNCTIONS
Function
INT(x)
NINT(x)
FLOOR(x)
FRACTION(x)
REAL(x)
Meaning
Arg. Type
truncate to integer part x
round nearest integer to x
greatest integer less than or equal to x
the fractional part of x
convert x to REAL
Examples
INT(-3.5)  -3
NINT(3.5)  4
NINT(-3.4)  -3
ϭ
REAL
REAL
REAL
REAL
INTEGER
Return type
INTEGER
INTEGER
INTEGER
REAL
REAL
FLOOR(3.6)  3
FLOOR(-3.5)  -4
FRACTION(12.3) 0.3
REAL(-10)  -10.0
 Other FUNCTIONS
Function
MAX(x1, x2, ..., xn)
MIN(x1, x2,…, xn)
MOD(x,y)
Meaning
maximum of x1, x2, ..., xn
minimum of x1, x2,…, xn
remainder x - INT(x/y)*y
Examples
Mod(2.2,2)=
2.2-int (2.2/2)*2=
2.2-1*2=
2.2-2=0.2
Example
Write a program to calculate the area of circle
PROGRAM circle_area
IMPLICIT NONE
!reads a value representing the radius of a circle,
!then calculates and writes out the area of the circle.
REAL :: radius, area
REAL, PARAMETER :: pi=3.141592
READ (*,*) radius
area = pi*radius*radius
WRITE (*,*) area
END PROGRAM circle_area
Ϯ
Example
PROGRAM Test
IMPLICIT NONE
INTEGER, PARAMETER :: result = 42
! Simple output statement...
PRINT *, ’Hello world!’
PRINT *, ’The result is ’, result
END PROGRAM Test
E
Exxaam
mppllee
Given base b and height h, the length of a special segment on a parabola
can be computed as follows:
ඥ૝ࢎ૛ ൅ ࢈૛ ൅
࢈૛
૛ࢎ ൅ ξ૝ࢎ૛ ൅ ࢈૛
࢒࢕ࢍ ቆ
ቇ
૛ࢎ
࢈
Write a program to read the values of base and height, and use the above
formula to compute the length of the parabola segment. Note that both base and
height values must be positive.
PROGRAM ParabolaLength
IMPLICIT NONE
REAL :: Height, Base, Length
REAL :: temp, t
WRITE(*,*) 'Height of a parabola : '
READ(*,*) Height
WRITE(*,*) 'Base of a parabola : '
READ(*,*) Base
! ... temp and t are two temporary variables
t
= 2.0 * Height
temp = SQRT(t**2 + Base**2)
Length = temp + Base**2/t*LOG((t + temp)/Base)
WRITE(*,*)
WRITE(*,*) 'Height = ', Height
WRITE(*,*) 'Base = ', Base
WRITE(*,*) 'Length = ', Length
END PROGRAM ParabolaLength
input values for Height and Base are 100.0 and 78.5, respectively. The
computed length is 266.149445.
ϯ
E
Exxaam
mppllee ((H
H..W
W))
Convert temperature at 30oC from Celsius to Fahrenheit .
Note:
Fo = Co*9/5+32
E
Exxaam
mppllee ((H
H..W
W))
Write a program to transforms the Cartesian coordinate (x,y) presentation
to the polar coordinates (r, ). Use the definitions
Sin = y/r , cos  = x/r , r = (x2 + y2).5
ϰ