Can I search a text file for a particluar word before recording data?

Hi,

The data output format of the program I am using is giving me some trouble when I try to import the data into MATLAB. I need to search the file for a specific word before MATLAB starts recording the data, and I can't see how to make fscan, textscan, or textread do this.

For example, below I have included two sections of a data output file (each file contains at least 100 sections, some contain almost 1000 sections). I wish to ignore everything except the "7760" located near the end of each section (on the lines that end with "Target"). My problem is that the text that surrounds the "7760" has a varrying length and size throught the file, so I can't tell MATLAB to directly skip it. Is there a way to search the file for "BACKSTOP" and then record the "7760" and then start looking for "BACKSTOP" again?

Thanks for your help!

   -     {CONSIDER ALL
   -      PLOT FACETS OVERLAY '1-5 Winston Cone: X=(0/10), Radius=0.5'
     Window Vertical: Y = -100.000     to  100.000      ( 200.000    )
          Horizontal: Z = -102.100     to  102.100      ( 204.200    )

   -      GRID ELLIPTIC Z -25 (0/10)-0.5 (0/10)+0.5 -2@0.5 100 100
   -        ROTATE Y -ATAN[(0/10)/25]
   -        SOURCE DIRECTION -(0/10) 0 25
 Source Z  angle for rays
    0.000        1    -7860
   -      TRACE
   -      CONSIDER ONLY FRONTSTOP BACKSTOP TARGET
   -      STATS ALL }

 Object     Rays     Flux
     4       100  0.000000      FRONTSTOP
     5         0  0.000000      BACKSTOP
     6      7760 0.7860000      Target
 -----------------------------
 TOTAL      7860 0.7860000

   -     {CONSIDER ALL
   -      PLOT FACETS OVERLAY '1-5 Winston Cone: X=(1/10), Radius=0.5'
     Window Vertical: Y = -100.000     to  100.000      ( 200.000    )
          Horizontal: Z = -102.100     to  102.100      ( 204.200    )

   -      GRID ELLIPTIC Z -25 (1/10)-0.5 (1/10)+0.5 -2@0.5 100 100
     7860 rays created in a ELLIPTICAL grid for a total of 7860

   -        ROTATE Y -ATAN[(1/10)/25]
   -        SOURCE DIRECTION -(1/10) 0 25
 Source Z  angle for rays
    0.229        1    -7860
   -      TRACE
## Total of   99.61 millisec (  93.60 millisec CPU) to trace 7,860
   -      CONSIDER ONLY FRONTSTOP BACKSTOP TARGET
   -      STATS ALL }

 Object     Rays     Flux
     4         0  0.000000      FRONTSTOP
     5       100  0.000000      BACKSTOP
     6      7760 0.7860000      Target
 -----------------------------
 TOTAL      7860 0.7860000

Answer 1

[Albert Yam]

Look for a specific keyword(s), not exactly sure about your example, perhaps something like this.

Keyword = 'Object     Rays     Flux';
while 1  
        line_str = fgetl(fid);      % Get the next line
        if line_str == -1            % -1 if fgetl fails or is at eof
            error([Keyword 'not found'])
        elseif strcmp(line_str, Keyword)  % Keyword found, break the loop.
            break;
        end
    end
%Next line, start collecting data here