I need to read this kind of file. I have problem reading the delimiters within the file.
xxxx
dd/mm/yyyy
text
text
angle
Number of points
-13.82|654781.695|292510.337|4.889|SD
0.00|654795.515|292510.337|4.373|P1
1.25|654796.765|292510.337|4.324|SD
1.29|654796.805|292510.337|4.657|SD
1.68|654797.195|292510.337|4.622|SD
......
(1) Read lines from the file into a string using the "(a)" format.
(2) Replace unwanted delimiters in the string with delimiters recognized by Fortran (spaces or commas).
(3) Get data from the string using an "internal read".
The program below illustrates steps (2) and (3).
program main
implicit none
character (len=20) :: str
integer :: i
real :: x,y
str = "321.1|5678.9"
do i=1,len_trim(str)
if (str(i:i) == "|") str(i:i) = " "
end do
print*,"str = '" // trim(str) // "'" ! output: '321.1 5678.9'
read (str,*) x,y
print*,"x, y =",x,y ! output: x, y = 321.1 5678.9
end program main
Related
How do you format a string to have constant width and be left-justified? There is the Aw formatter, where w denotes desired width of character output, but it prepends the spaces if w > len(characters), instead of appending them.
When I try
44 format(A15)
print 44, 'Hi Stack Overflow'
I get
> Hi Stack Overflow<
instead of
>Hi Stack Overflow <
Is there any simple Fortran formatting solution that solves this?
As noted in the question, the problem is that when a character expression of length shorter than the output field width the padding spaces appear before the character expression. What we want is for the padding spaces to come after our desired string.
There isn't a simple formatting solution, in the sense of a natural edit descriptor. However, what we can do is output an expression with sufficient trailing spaces (which count towards the length).
For example:
print '(A50)', 'Hello'//REPEAT(' ',50)
or
character(50) :: hello='Hello'
print '(A50)', hello
or even
print '(A50)', [character(50) :: 'hello']
That is, in each case the output item is a character of length (at least) 50. Each will be padded on the right with blanks.
If you chose, you could even make a function which returns the extended (left-justified) expression:
print '(A50)', right_pad('Hello')
where the function is left as an exercise for the reader.
To complete #francescalus excellent answer for future reference, the proposed solution also works in case of allocatables in place of string literals:
character(len=:), allocatable :: a_str
a_str = "foobar"
write (*,"(A,I4)") a_str, 42
write (*,"(A,I4)") [character(len=20) :: a_str], 42
will output
foobar 42
foobar 42
a bit ugly but you can concatenate a blank string:
character*15 :: blank=' '
print 44, 'Hi Stack Overflow'//blank
program test ! Write left justified constant width character columns
! declare some strings.
character(len=32) :: str1,str2,str3,str4,str5,str6
! define the string values.
str1 = " Nina "; str2 = " Alba " ; str3 = " blue "
str4 = " Jamil "; str5 = " Arnost " ; str6 = " green "
write(*,'(a)') "123456789012345678901234567890"
! format to 3 columns 10 character wide each.
! and adjust the stings to the left.
write(*,'(3(a10))') adjustl(str1), adjustl(str2), adjustl(str3)
write(*,'(3(a10))') adjustl(str4), adjustl(str5), adjustl(str6)
end program test
$ ./a.out
123456789012345678901234567890
Nina Alba blue
Jamil Arnost green
adjustl() moves leading spaces to the end of the string.
I suggest that you do not limit the number of output characters.
Change it to the following will work:
44 format(A)
print 44, 'Hi Stack Overflow'
I'm trying to write a code in Fortran 95 that read strings from a file and then print a frequency table of letters from the file. The file has a text like the example below, with no more than 128 characters per line:
Ablblb lbla sdrtwfwefw
Waerfaw efeafawef awef
Pefwae fwefawefw efawe
Fcicnj ioejo, o njcdid
Pweko jai, wadwed awdd
So I did one program that is working fine for the first letter (A or a), but the counter doesn't work for the rest of the letters and always print "0". This is what I did:
program read_file
implicit none
integer :: count, i, j, k, n
character(len=80) :: arch
character(len=128) :: line
character :: c, d
logical :: rexist
print *,'Name of the file (example: "text1.txt"): '
read *,arch
count=0
inquire(file=arch, exist=rexist)
if(rexist) then
open(unit=10, file=arch)
j=97
do i=65,90
c=achar(i)
d=achar(j)
do
read(unit=10, fmt='(A128)', end=999)line
n=len_trim(line)
do k=1,n
if(line(k:k)==c .or. line(k:k)==d)then
count=count+1
end if
end do
cycle
999 exit
end do
print *, "Letter ", c, " or ", d, " Total: ", count
j=j+1
count=0
end do
close(unit=10)
else
print *,"Invalid file!"
end if
end program read_file
The first count works fine (letter A or a) but it prints "0" for the rest of the letters. Is there something wrong with the DO loop that doesn't reset the variable count properly?
I am trying to repeat the string "k" to match the length of "text" without going over the length. So it would output "treetreetreetreetreet" and not "treetreetreetreetreetree". I really dont know where to start other than just outputing more characters than needed.
PROGRAM test
IMPLICIT NONE
CHARACTER*30 :: text, k
INTEGER :: times
text = 'hello my name is anon'
k = 'tree'
times = (LEN_TRIM(text)/LEN_TRIM(k)) + 1
WRITE(*,*) REPEAT(k,times)
END PROGRAM test
First, your sample program as-is doesn't produce treetreetreetreetreetree as you expect, it actually produces tree tree tree .... When you pass the string k to REPEAT, the spaces after tree also get repeated. You should trim the string before repeating it, such as REPEAT(trim(k),times).
There are several ways to solve your main problem - I recommend using what you have so far but reducing the final result to the length you want - in this case LEN_TRIM(text). A good way to do this is to store the output of REPEAT in a temporary variable and output only a subset of this final string.
With both of these modifications and some other cleanup, your code looks like:
program main
implicit none
character(len=30) :: text, k, str
integer :: times
text = 'hello my name is anon'
k = 'tree'
times = (LEN_TRIM(text)/LEN_TRIM(k)) + 1 ! -- Note integer division
str = REPEAT(trim(k),times)
write(*,*) str(1:LEN_TRIM(text))
end program main
which gives the desired output
> gfortran main.f90 && ./a.out
treetreetreetreetreet
I have the following code:
program main
character (len=15) :: abc = "te st tex t"
print *, trim(abc)
end program main
Which outputs:
te st tex t
I excepted all the whitespace to be removed but it wasn't. How can I remove all the whitespace from the string?
Trim will remove spaces only at the edges, not in the middle (this is common behaviour on almost all languages/libraries). If you want to remove all spaces in the string, you will have to create your own function to do this, iterating through the string.
Ex.:
program Test
implicit none
! Variables
character(len=200) :: string
! Body of Test
string = 'Hello World 7 9'
print *, string
call StripSpaces (string)
print *, string
contains
subroutine StripSpaces(string)
character(len=*) :: string
integer :: stringLen
integer :: last, actual
stringLen = len (string)
last = 1
actual = 1
do while (actual < stringLen)
if (string(last:last) == ' ') then
actual = actual + 1
string(last:last) = string(actual:actual)
string(actual:actual) = ' '
else
last = last + 1
if (actual < last) &
actual = last
endif
end do
end subroutine
end program Test
This was tested on intel compiler, not on gfortran, but I think it will work.
I was able to do this using the variable string library described here ( http://schonfelder.co.uk/is1539-2-99.htm ). The source code link is found in the introduction section of the ISO document.
Here is the code
program Console1
use ISO_VARYING_STRING
implicit none
! Body of Console1
character(LEN=50) :: text = 'Hello World John Mary '
character(LEN=50) :: res
print *, trim(text)
! 'Hello World John Mary'
res = REPLACE(text,' ','', every=.TRUE.)
print *, trim(res)
! 'HelloWorldJohnMary'
end program Console1
Here's a dirty, shameful way to eliminate the spaces. This is only likely to work if a compiler lays out a length-15 string in the same order and space as it would a 15-element array of characters. While this is likely to be true, and in my recent experience is true, it is not guaranteed to be so by the standard. That aside, this approach may be good enough.
! declarations
CHARACTER (len=15) :: abc = "te st tex t"
CHARACTER, DIMENSION(LEN(abc)) :: abc_array
! or CHARACTER, DIMENSION(:), ALLOCATABLE :: abc_array if your compiler supports
! automatic allocation
! transfer the string into an array of characters
abc_array = TRANSFER(abc,abc_array)
! eliminate the spaces, and transfer back to the string
abc = TRANSFER(PACK(abc_array,abc_array/=' '),abc)
! now all the spaces are at the end of abc so the following statement writes the
! string with no spaces
WRITE(*,*) TRIM(abc)
Use this approach at your own risk.
For those averse to TRANSFER perhaps a nice little recursive function would appeal. As written this depends on Fortran 2003's ability to automatically allocate character scalars, but it shouldn't be too hard to modify if your compiler doesn't support this feature yet.
RECURSIVE FUNCTION stripper(string,ch) RESULT(stripped)
CHARACTER(len=*), INTENT(in) :: string
CHARACTER, INTENT(in) :: ch
CHARACTER(:), ALLOCATABLE :: stripped
IF (LEN(string)==1) THEN
IF (string==ch) THEN
stripped = ''
ELSE
stripped = string
END IF
ELSE
IF (string(1:1)==ch) THEN
stripped = stripper(string(2:),ch)
ELSE
stripped = string(1:1)//stripper(string(2:),ch)
END IF
END IF
END FUNCTION stripper
You can try this:
program test
!erase blank space in a string
!run over every character of the string and just take every non-blank in other variable.
implicit none
character (len=100) str1,str2
integer i
str2='' !in this variable will be save non-blank spaces
str1=' a b c de ' !Test string with blank spaces
write(*,*)len_trim(str1), str1
do i=1,len(str1)
if (str1(i:i).ne.' ')str2=trim(str2)//trim(str1(i:i))
end do
write(*,*)len_trim(str2), str2
end
I am trying to put an input string into sub-string arrays. The number of data in the input file are less than 10 but unknown. The number of spaces between each data is also unclear.
Example:
Asd B Cwqe21 Ddsw Eww
I am quite novice to Fortran, so I do not know which format I should use. My problem is that I do not know the number of data (here I assumed that there are 5), so how can I make the code work?
I tried the following which did not work:
CHARACTER (LEN=100), DIMENSION(10) :: string
READ (1,*) (string,I=1,10)
It seems that the error I got was because there was no 6th string to read and put into string(6).
I tried using the "Index" to find the space, but since I do not know how many spaces are in the string, it did not help me.
I don't know if this is more or less elegant/efficient than the standard approach in M.S.B's comment, but an interesting alternative.
integer istart,nw
character (len=100) line,wd,words(100)
open(1,file='t.dat')
read(1,'(a)')line
istart=1
nw=0
do while(len(trim(line(istart:))).gt.0)
read(line(istart:),*)wd
istart=istart+index(line(istart:),trim(wd))+len(trim(wd))
nw=nw+1
words(nw)=trim(wd)
enddo
write(*,*)trim(line)
write(*,*)('/',trim(words(k)),k=1,nw),'/'
end
An inefficient approach that is simple to program is to try to read the maximum number of items, and if this fails to successively try to read one fewer items until the read is successful, as shown below:
program xread_strings
integer, parameter :: nw = 10
character (len=1000) :: text
character (len=20) :: words(nw)
integer :: i,ierr,nread
text = "Asd B Cwqe21 Ddsw Eww"
nread = 0
do i=nw,1,-1
read (text,*,iostat=ierr) words(:i)
if (ierr == 0) then
nread = i
exit
end if
end do
if (nread > 0) write (*,*) "read ",nread," words: ",("'"//trim(words(i)) // "' ",i=1,nread)
end program xread_strings
! g95 Output:
! read 5 words: 'Asd' 'B' 'Cwqe21' 'Ddsw' 'Eww'