Addition
A+B
A+B
Subtraction
A-B
A-B
Multiplication
A x B
A*B
Division
A : B
A/B
Exponentation
A
A**3
Fortran notes-1
CONSTANTS AND VARIABLES
The variable names that begin with the letters I,J,K,L,M,N are considered integers unless they are defined otherwise.
integer a
real b
double precision dtemp(50)
complex cx(100)
character*4 code, name
character*(*) name(n)
parameter (pi=3.141593)
Arithmetic operations
Pi=3.141593
|
Addition |
A+B |
A+B |
|
Subtraction |
A-B |
A-B |
|
Multiplication |
A x B |
A*B |
|
Division |
A : B |
A/B |
|
Exponentation |
A |
A**3 |
Intrinsic functions
|
SQRT(X) |
Square root of x |
LOG(X) |
Natural log of x |
|
ABS(X) |
Absolute value of x |
LOG10(X) |
Common log of x |
|
SIN(X) |
Sine of x (in radians) |
INT(X) |
Integer part of x-converts a real value to an integer value |
|
COS(X) |
Cosine of x (in radians) |
REAL(I) |
Real value of I-converts an integer value to a real value |
|
TAN(X) |
Tangent of x(in radians) |
MOD(I,J) |
Integer remainder of I/J-Remainder or modulo function |
|
EXP(X) |
e raised to the x power |
|
|
Integer sum, n
Real averg
Averg= real(sum)/real(n)
Simple input and output
print*, weight, vol
read*, begin, ending
Formatted output
Print 5, time, distinc
5 format (1X,F5.1,2X,F7.2)
For integer values we use : I3 meaning 3 characters
F-specification: Is used to print real numbers in a decimal form.
Fw.d
XX.XXX
total width=w=6Decimal portion=d=3
E-specification:Real numbers may be printed in an exponential form
Ew.d
S0.XXXESXX
The symbol S indicates that positions must be reserved for both the sign of the value and the sign of the exponent in case they are negative.
Total width=w=10
Decimal portion=XXX=3
Complete programs
PROGRAM TEST
.....
STOP
END
Logical expressions
|
.EQ. |
Equal to |
.LE. |
Less than or equal to |
|
.NE. |
Not equal to |
.GT. |
Greater than |
|
.LT. |
Less then |
.GE. |
Greater than or equal to |
|
.AND. |
.OR. |
.NOT. |
Logical
if statementIf (a.lt.b) sum=sum+a
If (a.eq.b) then
Print*, "hello"
End if
If (
logical expression 1) thenStatement 1
...
statement n
if (
statement n+1
...
statement m
end if
statement m+1
...
statement p
end if
If (logical expression 1) then
Statement 1
...
statement n
else
Statement n+1
...
statement m
end if
If (
logical expression 1) thenStatement 1
...
statement m
else if (
logical expression 2) thenStatement m+1
...
statement n
else if (
logical expression 3) thenStatement n+1
...
statement p
else
Statement p+1
...
statement q
end if
WHILE LOOP STRUCTURE
n
IF (logical expression) THENStatement 1
...
statement m
GO TO n
END IF
DO LOOP
Do k index=initial,limit, increment
....
k continue
Example:
The sum of 1+2+3+...+50
Sum=0
Do 10 number=1,50
Sum=sum+number
10 continue
