Abaqus *.inp file created using Matlab

Question

I was trying to do parametric studies in ABAQUS. I created an *.inp file (master) using GUI in abaqus, then wrote a matlab code to create a new *.inp file using the master. Master *.inp file can be found here and will be required to run the code. In the new *.inp file everything was same as the master except a few specific lines which I am changing for parametric studies, code is given below. I am getting the files nicely but the problem is ABAQUS can't read the file and gives error messages. By visual inspection I don't find any faults. I guess matlab is writing the *.inp file in some other format which ABAQUS can't interpret.

clc;
%Number of lines to be copied
total_lines=4538; %total number of lines
lines_b4_RP1=4406; % lines before reference point 1

%creating new files
for A=0
    for R=[20 30 40 50 100 200 300 400 500]
        fileroot = sprintf('P_SHS_120X120X1_NLA_I15_A%dR%d.inp', A,R);
        main_inp=fopen('P_SHS_120X120X1_NLA_I15_A0R10.inp','r'); %inputting the main inp file to be copied
        wfile=fopen(fileroot,'w+'); %wfile= writing the new file
        for i=1:total_lines
            data=fgets(main_inp);
                if  i<lines_b4_RP1
                    fprintf(wfile,'%s\n', data);
                elseif i==lines_b4_RP1
                    formatline1=('%s\n');
                    txtline='*Node';
                    fprintf(wfile, formatline1 ,txtline);
                elseif i==(lines_b4_RP1+1)
                    formatline2=('%d%s%d%s%d%s%d\r\n');
                    comma=',';
                    refpt1=1;
                    xcoord1=R*cosd(A);
                    ycoord1=R*sind(A);
                    zcoord1=-20;
                    fprintf(wfile, formatline2, refpt1,comma,xcoord1,comma,ycoord1,comma,zcoord1);
                elseif i==(lines_b4_RP1+2) 
                    fprintf(wfile, formatline1 ,txtline);
                elseif i==(lines_b4_RP1+3)
                    refpt2=2;    
                    xcoord2=R*cosd(A);
                    ycoord2=R*sind(A);
                    zcoord2=420;
                    fprintf(wfile, formatline2 ,refpt2,comma,xcoord2,comma,ycoord2,comma,zcoord2);
                elseif i>(lines_b4_RP1+3)
                    fprintf(wfile,'%s\n', data);
                else break;
                end
        end        
        fclose(main_inp);
        fclose(wfile);
    end
end

Thanks in advance.

N.B. A sample *.dat file containing the error message is given here.

Please put the error message from Abaqus to your question. – hgazibara May 17 '15 at 07:00 — hgazibara, May 17 '15 at 07:00
Sample message file (*.dat) added in the question. – Anwar Saadat May 17 '15 at 10:06 — Anwar Saadat, May 17 '15 at 10:06

score 0 · Answer 1 · answered May 18 '15 at 20:16

You are using fgets to get each line of the input file. From the matlab help:

fgets: Read line from file, keeping newline characters

You then print each line using

fprintf(wfile,'%s\n', data);

This creates two newlines at the end of each data line in the file. A second problem in your file is that you use \r\n in your format specifier. In matlab (unlike C) this will give you two newlines. e.g.

>> fprintf('Hello\rWorld\nFoo\r\nBar\n')
Hello
World
Foo

Bar
>>

I would suggest in future to test this approach with a much simpler format that you can use. Also there is a

*preprint

option that allows you to echo the contents of the input file back into the dat file. This creates big dat files, but it is useful for debugging.

Dear Will, Thanks for all your suggestions. I got another idea of the mistake that I am reading and printing all the lines using '%s' but file itself is a combination of string, decimal and float. — Anwar Saadat, May 19 '15 at 05:05
fgets has read each line as a string, so i don't see %s as a problem? Also if this answered your question, please vote it up. I think you should test your matlab code with a simpler abaqus input file. — will, May 19 '15 at 12:51

Abaqus *.inp file created using Matlab

1 Answers1