fopen function in MATLAB

I am trying to open an ABAQUS input file via "fopen" function in MATLAB, but i am unable to open it.

[Steven Lord]

What does "unable to open it" mean in this context?

• Do you receive warning and/or error messages? If so the full and exact text of those messages (all the text displayed in orange and/or red in the Command Window) may be useful in determining what's going on and how to avoid the warning and/or error.
• Does it do something different than what you expected? If so, what did it do and what did you expect it to do?
• Did MATLAB crash? If so please send the crash log file (with a description of what you were running or doing in MATLAB when the crash occured) to Technical Support so we can investigate.

What does the second output from fopen say when MATLAB was unable to open the file?

[Sushant]

I have actually created an ABAQUS input file. I want to open that input file in MATLAB via fopen function. However, it is null vlaues after executing in MATLAB.

[Steven Lord]

Can you show us your fopen call and how you're trying to use the file identifier returned by fopen?

[Sushant]

I am pasting some lines of my code here, below.

fileID = fopen('new1.txt');
formatSpec = '%f';
N = 8;
% reads file data, using the formatSpec N times
% c_h: cell header
c_h = textscan(fileID,formatSpec,N,'delimiter','|')
% Read coordinates for nodes on the two opposite surfaces
% Save them in a cell array whose first and fourth columns are node #
% rest columns are x,y,z coordinates
% c_cord
c_cord = textscan(fileID,'%d %f %f %f %d %f %f %f')
fclose(fileID);

[Jan]

@Sushant: Whenever you try to open a file, check the success:

[fileID, msg] = fopen('new1.txt');
assert(fileID > 0, msg);

I guess, that using an absolute path solves the problem:

[fileID, msg] = fopen('C:\Path\To\WhereTheFileIs\new1.txt');
assert(fileID > 0, msg);

Answer 1

[Sivapriya Srinivasan]

Hey Sushant,

Here are some possible solutions when you are unable to open an ABAQUS input file via ‘fopen’ function in MATLAB

1.Check file format: ABAQUS input files are typically text files, but they may have a different file extension, such as ".inp". You can try opening the file with a text editor to check its format.

2.Check file encoding: ABAQUS input files are typically encoded in ASCII format. Make sure that the file is encoded in ASCII and not in some other encoding format.

3.Check the file path: Make sure that the file path you are providing to the ‘fopen’ function is correct. If the file is not located in the current working directory, you will need to provide the full path to the file.

4.Check file permissions: Ensure that you have read permissions for the file. If the file is write-protected, you may not be able to open it.

5.Use the correct mode: Make sure that you are using the correct mode when opening the file. For example, if you want to read from the file, you should use the "r" mode. If you want to write to the file, you should use the "w" mode.

If none of these solutions work, you may need to provide more information about the error you are encountering.