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Luc Maisonobe commented on MATH-181: ------------------------------------ The patch has been commited as of r615856, including the addition of a check for denominatorDigits value as suggested by Phil. I will probably look more in depth on this issue, because I think some improvements can be made. Continued fractions are a very efficient way to approximate doubles. Their accuracy is linked to the *square* of the denominator of the first ignored term. So I think converting the number of digits to a max denominator simply as 10^d is too much. So I don't close the issue yet. > Specify the maximum of digits when parsing a Fraction > ----------------------------------------------------- > > Key: MATH-181 > URL: https://issues.apache.org/jira/browse/MATH-181 > Project: Commons Math > Issue Type: Improvement > Affects Versions: 1.1 > Reporter: Niall Pemberton > Priority: Minor > Attachments: MATH-181-FractionDigitsLimit-v2.patch, > MATH-181-FractionDigitsLimit.patch > > > Firstly, thanks for the Fraction code - I've adapated it for something I'm > working on and I didn't have a clue how to convert a decimal to a fraction :) > Excel spreadsheets have the facility to specify a fraction format where you > specify the maximum number of denominator digits to display. > So for example: > format "?/?" displays decimal values formatted in the range 1/2 to n/9 > format "??/??" displays decimal values formatted in the range 1/2 to n/99 > format "???/???" displays decimal values formatted in the range 1/2 to > n/999 etc > In excel then the value 0.6152 displays as 3/5, 8/13 and 510/829 respectively > for the above 3 formats. > I'm attaching a patch for the Fraction class which adds a new constructor > where the maximum number of digits can be specified, rather than the epsilon > value. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.