Fortran 90 Program for Processing Output Files | Looping Through File Names

[jd1828]

Im trying to write a program in fortran 90 to process some output files that i have. Here is the problem I am having. All of the output files are named file.datA, file.datB,...ect. I set the variable "file" to equal file.dat. I want the program to run through a loop and each time change the name of "file". Basically I need to add A-Z on the end each time it reads the file.

 

[PerennialII]

Im trying to write a program in fortran 90 to process some output files that i have. Here is the problem I am having. All of the output files are named file.datA, file.datB,...ect. I set the variable "file" to equal file.dat. I want the program to run through a loop and each time change the name of "file". Basically I need to add A-Z on the end each time it reads the file.

... wonder if you could do it simply by defining a new character variable by trimming (using TRIM and some "editing suffix" in between, like // to ditch spaces etc.) 2 other chars together, and using the new one in the loop as the filename.

 

[ravenprp]

Hello,

Thank you for sharing your problem with writing a Fortran 90 program to process output files. It seems like you are facing a challenge in looping through file names. I would be happy to provide some guidance on how to approach this problem.

Firstly, it is important to understand that in Fortran 90, file names are treated as character strings. This means that you can manipulate them using string operations such as concatenation, slicing, and indexing. With this in mind, we can devise a solution to your problem.

One approach is to use a DO loop to iterate through the alphabets A-Z and use the string concatenation operator // to append them to the file name. For example, your loop could look something like this:

DO i = 1, 26
file = "file.dat" // CHAR(i+64)
! code to process the file
END DO

In this loop, the variable "i" takes the values from 1 to 26, and CHAR(i+64) converts the integer value to its corresponding ASCII character. This way, in each iteration, the file name will be updated with a different alphabet at the end.

Another approach is to use the intrinsic function "TRIM" to remove the trailing spaces from the file name and then append the alphabets. For instance, your loop could look like this:

DO i = 1, 26
file = TRIM(file) // CHAR(i+64)
! code to process the file
END DO

This approach eliminates the need to specify the file name in quotes, making it more flexible.

I hope these suggestions help you in solving your problem. Please let me know if you have any further questions or need clarification on any of the above. Best of luck with your program!