Fundamental data types

1

• Fundamental data types
• List-directed input/output

2
Fundamental types of numbers

• Integers
• Whole numbers (positive/negative/zero)
• Examples
• 1952
• 3456787890123
• 0
• -2334567
• Typical range on a 32-bit computer
• -2 x 109 to 2 x 109

3
Fundamental types of numbers

• Reals
• /- xxx.yyyyy
• xxx integer part
• yyyyy fractional part
• A better representation
• Sign /-
• Mantissa a fraction between 0.1 and 1.0
• Exponent x 10e
• - 0.923456 x 10-6 or -0.923456e-6

4
real and integer variables

• Variable declaration
• type name
• type name1, name2,
• integer a, b, c
• real x, y, z

5
Arithmetic expressions

• A combination of variables, constants, operators,
  parentheses
• (4PiRadius 2 1.2098)/2.3

6
Assignment

• name expression
• replace the content of the variable name with the
  result of the expression

7
List-directed input and output

• read , var_1, var_2,
• only variables!
• print , item_1, item_2,
• variables, constants, expressions,
• Value separators
• Comma (,)
• Space
• Slash (/)
• End-of-line

8
List-directed input and output

• Two consecutive commas
• a null value is read
• the value of the variable is not set to zero,
  simply its value is not changed!
• If the terminating character is a slash then no
  more dataitems are read processing of the input
  statement is ended
• Example

9
Character data

• A B C D E F G H I J K L M N O P Q R S T U W X Y
  Za b c d e f g h i j k l m n o p q r s t u w x y
  z0 1 2 3 4 5 6 7 8 9? - / ( ) , . ' ! "
  lt gt ?
• Declaration
• character (lenlength) name1, name2,
• character (len6) a, b, c
• character (len103) a
• character (len10) b
• Assignmenta "What a lovely afternoon!" a will
  have the value of "What a lovely
  afternoon!??????"b ab will have the value of
  "What a lov"

10
Character data

• Concatenation
• Operator //
• Example
• character (len10) a, b, c
• a "James"
• b "Bond"
• c trim(a)//"?"//trim(b)
• c will have the value of "James Bond"

11
Named constants

• type, parameter name1constant_expression1,
• real, parameter pi3.1415926, pi_by_2 pi/2.0
• integer, parameter max_lines 200

12
Example
! Name Dursun Zafer Seker ! Tel
90 [phone] (office) ! Address ITU,
Faculty of Civil Engg. 80626 Maslak, Istanbul !
Purpose Converts Celsius to Fahrenheit ! Date
March 14, 2001 ! Comments..... ! program
Cel_Fah real CEL, FAH print , "Please
Enter Celsius Temperature" read , CEL FAH
9.0CEL/5.032.0 print,"Celsius ",CEL,"
Fahrenheit ", FAH end program Cel_Fah
13
Example
! Name Dursun Zafer Seker ! Address
ITU, Faculty of Civil Engg. 80626 Maslak,
Istanbul !! Date March 14, 2001 !
Comments..... ! program Sin_Cos_Tan real
angle,S,C,T,RAD real, parameter PI
3.1415926 print , "Please Enter Value of
Angle in degrees" read , angle RAD
angle/(180.0/PI) S sin(RAD) C cos(RAD)
T tan(RAD) print,"angle ",angle," Sinx
",S," Cosx ",C," Tanx ",T end program
Sin_Cos_Tan
14
program list_directed_input_example!integersinte
gerint_1, int_2, int_3realreal_1, real_2,
real_3!initial valuesint_1-1int_2-2int_3-3
real_1-1.0real_2-2.0real_3-3.0!read
dataread, int_1, real_1, int_2, real_2,int_3,
real_3!print new valuesprint, int_1, real_1,
int_2, real_2,int_3, real_3end program
list_directed_input_example
Example
15
Example
!this program is calculates area of a
rectangle program area_calculation use
rec reala,b,al print , "enter two edges of the
rectangle" read , a,b alarea (a,b) print ,
"a",a print,"b",b print , "area_of_rectangle"
,al endprogram area_calculation
16
Exercises

• Write a program for the following equations
• abc
• write a program to input a number x and print the
  values of x-1, x2 and x2 x-2,
• write a program which read a Fahrenheit
  temperature and then convert it to Celcius,
• write a program that calculates µ value from
  following equation
• µ (ma mb) / (ma mb)

17
Example PROBLEM Prepare a computer program
which calculates   the volume the
weight of a steel cylinder having the following
initial values   radius r 70
cm height h 280 cm   density
d 7.89 kg / dm3