The usual way to print floating-point values rounded and padded to two decimal places:

    printf "%.02f\n", $float
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Or, if you need to use a so-formatted string representation of your floating point number for something else:

    $string = sprintf "%.02f", $float
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Read up on s?printf in the doc for a full description of what you can do with the formatting string (the %.02f part of the above examples).