1 More Control over INPUT and OUTPUT (I / O) The interface between the user and the computer Formats and edit descriptors Input editing Output editing read, write and print statements More powerful formats

2 More Control over INPUT and OUTPUT (I / O) The input and output facilities of any programming language are extremely important, because it is through these features of the language that communication between the user and the program is carried out. F, therefore, provides facilities for input and output at two quite different levels. As are given before, list-directed input and output statements that provide the capability for straightforward input from the keyboard and also the output to the display or printer. These list-directed “i/o” - statements, however, allow the user very little control over the source or layout of the input data.

3 F allows the programmer, to specify exactly how the data will be presented and interpreted, from which of the available input units it is to be read how the results are to be displayed to which of the available output units the results are to be sent. More Control over INPUT and OUTPUT (I / O)

4 INTERFACE between the USER and the COMPUTER Considering the following 9 – digit input data there are enormous number of possible interpretations : Data : , 2, 3, 4, 5, 6, 7, 8, and , 456, , 0.45, 67, etc.

5 FORMATS and EDIT DESCRIPTORS An input statement must contain three distinct types of information where the data is to be found where it is to be stored in the computer’s memory how it is to be interpreted Similarly, an output statement must define where the results are currently stored where they are to be sent in what form they are to be displayed.

6 INPUT EDITING EXAMPLES of INPUT DATA : read “ ( i 3, i 3, i 3 )”, n1, n2, n3 ! n1 = 123, n2 = 456, n5 = 789 read “ ( t 5, i 2, t 6, i 2, t 2, i 4 )”, x, y, z ! x = 56, y = 67, z = 2345 read “ ( f 9.4 )”, real_num ! real_num = read “ ( f 3.1, f 2.2, f 3.0 )”, r1, r2, r3 ! r1 = 12.3, r2 = 0.45, r3 =

7 EXAMPLE for formatting of real numbers using “ f – edit descriptor “ depending on the two different INPUT DATA : read “ ( f 3.1, f 2.2, f 3.0 )”, s1, s2, s3 DATA 1 DATA s1 contains : s2 contains : s3 contains :

8 EXAMPLEs for formatting of an input real number in different ways using “ a – edit descriptor “ real number is : – e d E

9 EXAMPLEs for formatting of an input – character type using “ a – edit descriptor “ character ( len = 10 ) : : ch1 character ( len = 6 ) : : ch2 character ( len = 15 ) : : ch3 Depending on the above-given declaration the formats may have the following forms in read statements : read “ ( a10, a6, a15 )”, ch1, ch2, ch3 or read “ ( a, a, a )”, n1, n2, n3

10 LOGICAL DATA - INPUT EDITING The edit descriptor is used with logical data, and takes the following form, where upper case “ L” is used to avoid the potential confusion with the digit “ 1 “ that can be caused to human readers by using the lower-case form : L w “ w “ caharacters are used to derive either a “ true “ value, a “ false “ value or an error.

11

12 Any of the following are acceptable as representing true :  t  true .T .true.  truthful while the following will all be interpreted as false :  F  False .f.  futile LOGICAL DATA - INPUT EDITING

13 OUTPUT EDITING The following figure shows the main edit descriptor that are available for output. EXAMPLE for “i” edit descriptor tom = 23 dick = 715 harry = -12 print *, “( i 5, i 5, i 5 )”, tom, dick, harry This statement produce following line of output (where the symbol # represents a space ) : ###23##715##-12

14 EXAMPLE for “f” edit descriptor : x = y = z = print *, “( f 10.3, f 10.3, f 10.3 )”, x, y, z This statement produce following line of output (where the symbol # represents a space ) : #####3.142## ### OUTPUT EDITING

15 EXAMPLE : program tabular_output real, parameter : : third = 1.0 / 3.0 real : : x integer : : i do i = 1, 10 x = i print “( f 15.4, f 15.4, f 15.4 )”, x, sqrt (x), x**third end do end program tabular_output OUTPUT EDITING

16 In the above-given program the same edit descriptor has been repeated several times. A number, called a “repeat count”, may be placed before the “ i, f, a or L “ – edit descriptors to indicate how many times they are to be repeated. Depending on this, the format could be written more succinctly and İt is possible to write it more clearly. EXAMPLE : print “( i 5, i 5, i 5, f 6.2, f 6.2, f 6.2, f 6.2 )”, x, y, z, d, e, f, g or better print “( 3 i 5, 4 f 6.2 )”, x, y, z, d, e, f, g OUTPUT EDITING

17 Exercise 2 program test1 integer ::a,b real::c,d print*,"please enter an integer values which is more than 6 digit" read "(i4,t1,i4,t2,f4.1,t1,f4.2)",a,b,c,d print "(i4,a,i5,a,i5,a,f6.2,a,f6.2,a,f8.3)",a,& " minus",b," is",a-b,";",c," minus",d, " is",c-d end program test1

18 Exercise 3 program test2 character(len=6)::a,b,c Print*,”Please write your name” read "(a8,t1,a4,t1,a)",a,b,c print "(a10,tr12,a4,tr30,a)",a,b,c print "(a,t10,a,t52,a)",a,b,c end program test2

19 program five_digit_numbers integer::i integer,dimension(12)::arr arr = (/12345, 23456, 34567, 45678,& 90123, 12340, 24680, 46802,& 13579, 35791, 57913, 69649/) !output for single column format example print*,"Single column of numbers" do i = 1, 12 print "(t8,i2,1x,i5)",i,arr(i) end do !output for four rows of three numbers print "(2/t3,a/)","Four rows of three numbers " print "(t8,i2,1x,3(i5,1x))", 1,arr(1:3) print "(t8,i2,1x,3(i5,1x))", 2,arr(4:6) print "(t8,i2,1x,3(i5,1x))", 3,arr(7:9) print "(t8,i2,1x,3(i5,1x))", 4,arr(10:12) ! a single line of numbers print "(2/t3,a/)", "A single line of numbers " print "(t2,12(i5,1x))", arr end program five_digit_numbers

20 program multi_record_example real :: a,b a = b = write(unit=6,fmt="(t10,a,3/,a,f6.2,a,f6.2,a,///,f7.2,2/,a,f10.3)")& "Multi-record example", & " The sum of ",a," and",b," is", a+b, & " Their product is",a*b end program multi_record_example

21 program railway_time_table integer,parameter::n=5 integer::i real,dimension(n)::arrival,departure integer,dimension(n)::platform character(len=10),dimension(n)::destination arrival=(/9.23, 9.28, 10.41, 10.48, 11.15/) departure=(/9.25, 9.32, 10.53, 10.53, 11.18/) platform=(/2, 1, 3, 2, 1/) destination=(/"Edinburgh"," London","Sheffield",& "Newcastle"," London"/) write(unit=6,fmt="(/a/2x,7('='),3x,9('='),3x,8('='),3x,11('='))") & " Arrival Departure Platform Destination" do i = 1, n write(unit=6,fmt="(3x,f5.2,6x,f5.2,8x,i1,8x,a10)") & arrival(i),departure(i),platform(i),destination(i) end do end program railway_time_table

22 program test2 character(len=6)::a,b,c print *, " STEPPER... Entering PROGRAM. Press Enter" print*,"program test2" read * print *, " STEPPER... Before READ. Press Enter" print*,"read ""(a8,t1,a4,t1,a)"",a,b,c" read * read "(a8,t1,a4,t1,a)",a,b,c print *, " STEPPER... After READ. Press Enter" read * print "(a8,tr2,a4,tr3,a)",a,b,c print*,"print ""(a8,tr2,a4,tr3,a)"",a,b,c" print *, " STEPPER... After PRINT. Press Enter" read * print "(a,t10,a,tr2,a)",a,b,c print*,"print ""(a,t10,a,tr2,a)"",a,b,c" print *, " STEPPER... After PRINT. Press Enter" read * print *, " STEPPER... Before ENDPROGRAM. Press Enter" print*,"end program test2" read * end program test2

23 program tabular_output real, parameter :: third = 1.0 / 3.0 real :: x integer :: i do i = 1, 10 x = i !print "(f15.4, f15.4, f15.4)", x,sqrt(x),x**third print "(3f15.4)", x,sqrt(x),x**third end do end program tabular_output

24 program aa character (len=50) :: a, b, c, d, e integer :: i, j a = "aaa bbbb ccccc dddddd eeeeeee" print *, a i = index(a," ")+1 b = a(:i-2) print *, b c = a(i:) print *, c j = index (c," ") +1 d = c(:j-2) print *, d e = d(j:) print *, e end program aa

25 program character_searc_function !examle for index, you can olso try scan and verify character (len=50) :: a, b, c, d, e integer :: i, j a = "bbb cccc ddddd eeeeee" print *, a i = index(a,"d") !Calculates how many chracter before and including "c" print*,"i",i b = a(:i-2) print *, b c = a(i:) print *, c j = index (c," ") +1 d = c(:j-2) print *, d e = d(j:) print *, e end program character_searc_function

26 ! Assignment statements with constant expressions. program C01 implicit none integer, parameter :: NAME_LENGTH = 21 real :: Avogadros_Number integer :: Many complex :: Z logical :: Flag character (len = NAME_LENGTH) :: Name ! start program C01 Many = ! Integer type Avogadros_Number = e23 ! Real type Z = (0.0, 1.75e8) ! Complex type Flag =.true. Name = " Mustafa " ! Character type, length 21 write (unit = *, fmt = *) Many, Avogadros_Number, Z, Flag, Name stop end program C01

27 ! Assignment statements with variable expressions. module C02M implicit none public :: Assign_2 contains subroutine Assign_2( ) ! Type declarations with initialization: real, save :: Y = 1.23, Pi = integer, save :: Counts = 173 character (len = 8), save :: I = " Optics " logical, save :: Flag =.true. ! Type declarations without initialization: real :: X, Theta integer :: Many character (len = 8) :: K logical :: Done ! start subroutine Assign_2 X = Y ! Real type Y = X Theta = Pi Many = Counts ! Integer type K = I ! Character type, length 8 Done = Flag ! Logical type write (unit = *, fmt = *) Y, Pi, X, Theta, Counts, Many, I, K, Flag, Done return end subroutine Assign_2 end module C02M program C02 use C02M implicit none ! start program C02 call Assign_2( ) stop end program C02

28 ! Assignment statements with arithmetic expressions. program C03 implicit none real, parameter :: GRAVITY = 9.8 real :: Old_Vol, Old_Press, Old_Temp, New_Vol, New_Press, New_Temp real :: Mass, Velocity, Kinetic_Energy, Pressure, Density, Height, Bernoulli integer, parameter :: J = 6 integer :: I ! start program C03 I = J + 1 write (unit = *, fmt = *) I read (unit = *, fmt = *) Old_Vol, Old_Press, Old_Temp, New_Press, New_Temp New_Vol = Old_Vol * (Old_Press / New_Press) * (New_Temp / Old_Temp) write (unit = *, fmt = *) Old_Vol, Old_Press, Old_Temp, New_Vol, New_Press, New_Temp read (unit = *, fmt = *) Mass, Velocity Kinetic_Energy = 0.5 * Mass * Velocity ** 2 write (unit = *, fmt = *) Mass, Velocity, Kinetic_Energy read (unit = *, fmt = *) Pressure, Density, Velocity, Height Bernoulli = Pressure + Density * (0.5 * Velocity ** 2 + GRAVITY * Height) write (unit = *, fmt = *) Pressure, Density, Velocity, Height, Bernoulli stop end program C03

29 program aa character (len=50) :: a, b, c, d, e integer :: i, j a = "aaa bbbb ccccc dddddd eeeeeee" print *, a i = index(a," ")+1 b = a(:i-2) print *, b c = a(i:) print *, c j = index (c," ") +1 d = c(:j-2) print *, d e = d(j:) print *, e end program aa program 0206 ! Asks the hour and the minute values of the ! present time and displays it as a sentence. integer :: hh,mm print *, " Input the hour, in the 24 hours format." read *, hh print *, " Input the minute." read *, mm print *, "" print *, " THE TIME IS ",mm," MINUTES AFTER ",hh end program 0206 ! Assignment statements with constant expressions. program C01 implicit none integer, parameter :: NAME_LENGTH = 21 real :: Avogadros_Number integer :: Many complex :: Z logical :: Flag character (len = NAME_LENGTH) :: Name ! start program C01 Many = ! Integer type Avogadros_Number = e23 ! Real type Z = (0.0, 1.75e8) ! Complex type Flag =.true. Name = " Mustafa Sezer" ! Character type, length 21 write (unit = *, fmt = *) Many, Avogadros_Number, Z, Flag, Name stop end program C01

30 program C02 use C02M implicit none ! start program C02 call Assign_2( ) stop end program C02 ! Assignment statements with variable expressions. module C02M implicit none public :: Assign_2 contains subroutine Assign_2( ) ! Type declarations with initialization: real, save :: Y = 1.23, Pi = integer, save :: Counts = 173 character (len = 8), save :: I = " Optics " logical, save :: Flag =.true. ! Type declarations without initialization: real :: X, Theta integer :: Many character (len = 8) :: K logical :: Done ! start subroutine Assign_2 X = Y ! Real type Y = X Theta = Pi Many = Counts ! Integer type K = I ! Character type, length 8 Done = Flag ! Logical type write (unit = *, fmt = *) Y, Pi, X, Theta, Counts, Many, I, K, Flag, Done return end subroutine Assign_2 end module C02M ! Assignment statements with arithmetic expressions. program C03 implicit none real, parameter :: GRAVITY = 9.8 real :: Old_Vol, Old_Press, Old_Temp, New_Vol, New_Press, New_Temp real :: Mass, Velocity, Kinetic_Energy, Pressure, Density, Height, Bernoulli integer, parameter :: J = 6 integer :: I ! start program C03 I = J + 1 write (unit = *, fmt = *) I read (unit = *, fmt = *) Old_Vol, Old_Press, Old_Temp, New_Press, New_Temp New_Vol = Old_Vol * (Old_Press / New_Press) * (New_Temp / Old_Temp) write (unit = *, fmt = *) Old_Vol, Old_Press, Old_Temp, New_Vol, New_Press, New_Temp read (unit = *, fmt = *) Mass, Velocity Kinetic_Energy = 0.5 * Mass * Velocity ** 2 write (unit = *, fmt = *) Mass, Velocity, Kinetic_Energy read (unit = *, fmt = *) Pressure, Density, Velocity, Height Bernoulli = Pressure + Density * (0.5 * Velocity ** 2 + GRAVITY * Height) write (unit = *, fmt = *) Pressure, Density, Velocity, Height, Bernoulli stop end program C03