Enjoy an ad free experience by logging in. Not a member yet? Register.

Results 1 to 6 of 6
Thread: Converting Decimals to Fractions

07182009, 12:39 AM #1
 Join Date
 Apr 2007
 Posts
 317
 Thanks
 24
 Thanked 3 Times in 3 Posts
Converting Decimals to Fractions
I know this is a rather odd post but I need to be able to convert a decimal to a fraction.
Really all i need to know to get what i have to work is being able to tell if a number is whole or not.
For instance if i have an accuracy set of .0625 = 1/16"
If i take my variable which is set to .5625 (9/16")
so if i take variable/accuracy in this case would equal 9. So this way i would know that the numerator would be 9 and my denominator would be 16.
If i take the same accuracy of 1/16 and now introduce a variable of 0.5 then it will give me a remainder.
I think i'm getting all jumbled up, if anyone has any insight this would be great.
07182009, 02:58 AM
#2
 Join Date
 Apr 2009
 Posts
 2,127
 Thanks
 1
 Thanked 426 Times in 424 Posts
Your post would be less odd if you described what you are actually trying to accomplish, and especially why.
But since for now that post is all there is, I'll try to get into that mumbo jumbo:
If that's all you want to do, that's quite easy. .5625 as a fraction is 5625/10000. If you want it in lowest terms, use the euclidian algorithm to compute the greatest common divisor.I know this is a rather odd post but I need to be able to convert a decimal to a fraction.
If that's all you want to know, that's quite easy too.Really all i need to know to get what i have to work is being able to tell if a number is whole or not.
number == parseInt(number)
will tell you if it's whole.
Don't know what you are doing there. You won't know your denominator would be 16; you put that information right into that calculation. You don't want to test all natural numbers just to find out the denominator, do you?For instance if i have an accuracy set of .0625 = 1/16"
If i take my variable which is set to .5625 (9/16")
so if i take variable/accuracy in this case would equal 9. So this way i would know that the numerator would be 9 and my denominator would be 16.
What remainder are you talking about? It will give you 8.If i take the same accuracy of 1/16 and now introduce a variable of 0.5 then it will give me a remainder.
I'm afraid insight into your problem is exactly what I am lacking. Please provide.I think i'm getting all jumbled up, if anyone has any insight this would be great.
07182009, 03:26 AM
#3
 Join Date
 Apr 2007
 Posts
 317
 Thanks
 24
 Thanked 3 Times in 3 Posts
I'm trying to take a given number whether it be .5625 or .3125 or .5 and convert it to an english fractional number such as 9/16, 5/16, or 1/2"
The user can also specify the accuracy for rounding purposes for the number. which was what i was talking about before if the user wants numbers rounded to the nearest 1/16" of an inch or nearest 1/4" I'm going to try what you've wrote already and see if it helps.
Thanks.
07182009, 04:45 AM
#4
Well, just multiply by 16 and round to the nearest integer. That gives you the numerator. 16 would, of course, be the denominator.
07182009, 08:27 AM
#5
 Join Date
 Jun 2002
 Location
 London, England
 Posts
 18,079
 Thanks
 203
 Thanked 2,542 Times in 2,520 Posts
Try this:
Code:<html> <head> <script type="text/javascript"> var roundTo = 16; // round to nearest 1/roundTo; function fraction() { var decimal = document.getElementById('dec').value; if ((!/^\d*\.\d+$/g.test(decimal))  (String(decimal).split('.')[1].length > 4)) { alert ("You must enter a decimal number (max 4 decimal digits)!"); document.getElementById('dec').value = ""; document.getElementById('dec').focus(); return false; } var whole = String(decimal).split('.')[0]; decimal = parseFloat("." + String(decimal).split('.')[1]); var num = "1"; for (var z=0; z<String(decimal).length2; z++){ num += "0"; } decimal = parseInt(decimal*num); num = parseInt(num); for (z=2; z<decimal+1; z++) { if (decimal%z==0 && num%z==0) { decimal = decimal/z; num = num/z; z = 2; } } var result = ((whole==0)?"" : whole+" ") + decimal + "/" + num; alert ("Fractional value = " + result); var d = num/roundTo; var n = Math.round(decimal/d); alert ("Rounded to nearest 1/" + roundTo + " inch = " + ((whole==0)?"" : whole+" ") + n + "/" + roundTo + " inch"); var HCF = 1; for (z=1; z<100; z++){ if (n%z == 0 && roundTo%z == 0) { HCF = z; } } var inch = " inch"; var simplified = (n/HCF +'/'+ roundTo/HCF); if (simplified == "1/1") { simplified = ""; whole ++; } else if (simplified == "0/1") { simplified = ""; } if (whole == 1) {inch = "inch"} else {inch = "inches"} if (!whole) {inch = "0 inches"} alert ("Simplified to: " + ((whole==0)?"" : whole + " ") + simplified + inch); } </script> </head> <body> <input type="text" name="dec" id= "dec" size="6" > <button onclick = 'fraction();'>Change decimal to fraction</button> </body> </html>
111,111,111 x 111,111,111 = 12,345,678,987,654,321
Last edited by Philip M; 07182009 at 01:01 PM. Reason: Improved
07182009, 10:39 PM
#6
 Join Date
 Mar 2009
 Posts
 248
 Thanks
 3
 Thanked 68 Times in 66 Posts
macleodjb:
Code:<!DOCTYPE HTML PUBLIC "//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <title>None</title> <meta httpequiv="ContentType" content="text/html; charset=utf8"> <script type="text/javascript"> function calcResult(nForm){ var nMeasurement = nForm['measurement'].value; var roundingFraction = nForm['roundTo'].value; if (!/^\.\d+$/.test(nMeasurement)) { alert('Invalid Measurement'); nForm['result'].value = ""; return; } if(!/^1\/\d{1,2}$/.test(roundingFraction)) { alert('Invalid Rounding Fraction'); nForm['result'].value = ""; return; } var nMeasureNumerator = nMeasurement.substring(1,nMeasurement.length); var nMeasureDenominator = Math.pow(10,nMeasureNumerator.length); var roundingFractionDenominator = roundingFraction.split("/")[1]; var roundingFractionNumerator = Math.round((nMeasureNumerator * roundingFractionDenominator) / nMeasureDenominator); while (roundingFractionNumerator % 2 == 0 && roundingFractionDenominator % 2 == 0) { roundingFractionNumerator = roundingFractionNumerator / 2; roundingFractionDenominator = roundingFractionDenominator / 2; } while (roundingFractionNumerator % 3 == 0 && roundingFractionDenominator % 3 == 0) { roundingFractionNumerator = roundingFractionNumerator / 3; roundingFractionDenominator = roundingFractionDenominator / 3; } nForm['result'].value = roundingFractionNumerator + "/" + roundingFractionDenominator; } function init(){ var nForm = document.forms[0]; nForm['convert'].onclick = function() { calcResult(nForm); } } navigator.appName == "Microsoft Internet Explorer" ? attachEvent('onload', init, false) : addEventListener('load', init, false); </script> <style type="text/css"> .center {textalign: center;} </style> </head> <body> <form action="" method="post"> <label>Decimal Measurement: <input type="text" name="measurement" class="center" size="12" value=".5625"></label> <br><br> <label>Round to Nearest: <input type="text" name="roundTo" class="center" size="5" value="1/16"></label> <br><br> <label>Result: <input type="text" name="result" class="center" size="5" readonly></label> <br><br> <input type="button" value="Convert" name="convert"> </form> </body> </html>
Last edited by 12 Pack Mack; 07192009 at 01:39 PM.