jquery/javascript how to calculate width faster
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I have a table with 100 columns. I'm running a loop through all the th elements, to explicitly set the width of each th.

    var $ths = $("table th");
    $ths.each(function (i, th) {
        var $th = $(th);
        var width = $th.width();
        $th.width(width);
    });

For 100 columns, this takes too much amount of time (more than 60s). Each "get width" call takes 500-700 ms. This is because it needs to generate layout every time, I get width. 

Question - Is there a faster way to get width?

Reason - I'm freezing header. For that I need to set width of each header to fixed pixel width. Everything is dynamic and pre-setting the width of each column in px is not an option.