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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. More Control over INPUT and OUTPUT (I / O).
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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
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.
More Control over INPUT and OUTPUT (I / O) 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.
INTERFACE between the USER and the COMPUTER • Considering the following 9 – digit input data there are enormous number of possible interpretations : • Data : 1 2 3 4 5 6 7 8 9 • 1 2 3 4 5 6 7 8 9 • 1, 2, 3, 4, 5, 6, 7, 8, and 9 - 123, 456, 789 • 12345 . 6789 • 1.23, 0.45, 67, 8900 • etc.
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.
INPUT EDITING EXAMPLES of INPUT DATA : 123456789 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 = 12345.6789 read “ ( f 3.1, f 2.2, f 3.0 )” , r1, r2, r3 ! r1 = 12.3, r2 = 0.45, r3 = 678.0 123456789 123456789 123456789
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 1DATA 2 123456789 .23.56.8 ---------------------- ----------------- s1 contains : 12.3 0.23 s2 contains : 0.45 0.5 s3 contains : 678.0 6.8
EXAMPLEs for formatting of an input real number in different ways using “ a – edit descriptor “ • realnumber is : 361.764 • 361.764 • 3.61764+2 • 361764–3 • 0.0361764e4 • 3617.64d-1 • 3.61764 E +2 • 361.764+0
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
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.
LOGICAL DATA - INPUT EDITING • 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
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
OUTPUT EDITING EXAMPLE for “f” edit descriptor : x = 3.14159 y = -275.3024 z = 12.9999 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##-275.302###-13.000
OUTPUT EDITING 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 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
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
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
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
program multi_record_example real :: a,b a = 12.25 b = 23.50 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
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
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
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
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 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
! 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 = 346021 ! Integer type Avogadros_Number = 6.0221367e23 ! 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
! 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 = 3.141592 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
! 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
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 = 346021 ! Integer type Avogadros_Number = 6.0221367e23 ! 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
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 = 3.141592 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