Hi Guys, thanks heaps for all your replies. that helped me understand more of reg exp in perl, but I'm not quite there yet :(
Graff, you're right in saying the sample has a lot of whitespaces. I copied and pasted the format as is. so the while loop looks like it's the way to go. the Coordinate field in vrml has thousands of those points where each set of 3 represents (x,y,z) coordinates. A snippet of the code looks like 
        geometry IndexedFaceSet {
            coord
            Coordinate {
                point [  265.185 -166.225 -510.375,
                     264.529 -166.901 -513.43,
                     269.321 -166.425 -510.918,
                     271.021 -166.956 -513.279,
                     271.223 -167.21 -514.637,
                     272.77 -166.984 -514.019,
                     270.767 -167.555 -516.859,
                     268.668 -167.344 -515.143,
                     272.884 -167.285 -515.945,
                     266.267 -167.539 -516.835,
                     267.193 -167.766 -518.544,
                     272.686 -167.438 -517.418,
                     269.214 -167.83 -519.399,
                     274.761 -166.996 -515.928,
                     275.801 -166.946 -519.035,
                     264.372 -167.451 -517.076,
                     266.21 -167.785 -519.148,
                     263.801 -167.367 -516.587,
                     269.266 -167.919 -521.463,
                     271.322 -167.821 -522.477,
                     266.656 -168.197 -528.597,
                     269.644 -168.342 -527.906,
                     267.007 -167.981 -524.961,
                     264.07 -167.493 -517.639,
                     263.244 -167.65 -520.707,
                     267.726 -167.91 -521.09,
                     264.468 -167.739 -523.493]
                  }

[download]
This would give the coordinates for points defining one block.
The model has a number (around 30) of blocks within it, each with a Coordinate field. and I need to read all the points from all the blocks. I tried playing around with the few suggestions provided, but still does not have to right reg exp to match the format I am seeking. what does colon (:) mean in ((?:\s*\d+){3}) I tried something like 

while ( $array =~ /\[         #open sq bracket
    ((?:\s*\d+){3})       #match 3 numerics
    ,
    ((?:\s*\d+){3})
    \]
    /gx)
{
    print "Grr: get inside this loop";
}

[download]
on a test sample where there were only 2 sets of (x,y,z) coordinates within sq brackets. the print statement is not getting executed. thanks again for your precious help!!:) Phoenix.

In reply to Re^2: accessing specific data in a file by phoenixQueen
in thread accessing specific data in a file by phoenixQueen

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