Extract part of the text file

Sorry if duplicated post.. but i don't know where I should put the question....

There is the situation... I am using ABAQUS to simulate some tests, and i have to edit the input file (normal text file) to incorporate switches that are not available in the GUI version of ABAQUS.

Two Question

Question 1:-

Is it possible to: search for two keywords, then select the lines between them and delete it?

the sample input file is as follow:

** 
** STEP: Eigen
** 
(SOME MORE LINES)
** FIELD OUTPUT: F-Output-1
** 
*Output, field, variable=PRESELECT
*End Step
** ----------------------------------------------------------------
** 
** STEP: Ax Load
**

the first keyword will be STEP: Eigen, and the second one is STEP: Ax Load. What i hope matlab can do is: search for STEP: Eigen, remember the line number search for STEP: Ax Load, remember the line number delete all the lines in between the two saved lines.

Question 2:- At the end of the input file, I need to add two lines below the keyword. The sample input file is as follow:

*Output, field, variable=PRESELECT
** 
** HISTORY OUTPUT: H-Output-1
** 
*Output, history, variable=PRESELECT
*End Step

The keywords will be: *Output, history, variable=PRESELECT and i want to add two lines, something like: *node file, global=yes U

I will be very thank to the person that can help me on this....

Thank You!!!

Answer 1

[Geoff]

I would do it as follows:

First, slurp the entire file into a cell array.

fileID = fopen('input.txt', 'r');

lines = {};
while 1
  line = fgetl(fileID);
  if line == -1 break;
  lines{end+1} = line;
end

fclose(fileID);

Now search for your open and closing tags.

fnFindLineWithText = @(arr,txt) ...
  find(cellfun(@(x) ~isempty(regexp(x,txt)), arr), 1);

openIdx = fnFindLineWithText(lines, 'STEP: Eigen');
closeIdx = fnFindLineWithText(lines, 'STEP: Ax Load');

if ~isempty(openIdx) && closeIdx > openIdx
  % You have your lines.
end

I'll leave the rest as an exercise for you =)

-g-

[Thomas Luk]

Thank you so much, the "regexp" solves my problem