Rounding error with litres - Fuelly Forums

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Old 07-07-2015, 09:56 AM   #1
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Rounding error with litres

When adding a fuel-up I've noticed that after putting in the cost/litre, litres (a round 15 litres in this example) and the web form calculates the total price, it alwyas amends the litres value from 15.000 to 15.004. If I manually adjust it back to 15.000, it always rounds up when I tab out of the form field.

I know this is a miniscule discrepancy, but I'm still puzzled as to why it's rounding the fill amount, as opposed to the calculated price (even if it calculates to three decimal places, then rounds up or down as the retailer does to two decimal places). If you used Fuelly religiously for a year, your MPG statistics might be skewed by a significant enough amount to make a tangible difference.

Also I've noticed sometimes if you enter a price/litre, amount filled and it auto-calculates the total cost, if you adjust the price it adjusts the amount filled and keeps the price the same -- or adjusts another value! (this is all in Chrome). You have to blank all the fields and start over; I would have expected changing the price per litre to adjust the total cost, as opposed to the amount filled.

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Old 07-07-2015, 01:42 PM   #2
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Thanks for the feedback.
We'll look into this.

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Old 11-30-2015, 10:39 AM   #3
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I'm having the same issue here in the US - just with gallons instead of litres. Several weeks ago, I noticed that after entering the number of gallons and cost per gallon, Fuelly would calculate the fill-up cost correctly, but would slightly change the number of gallons I entered. On at least one occasion, it kept "fighting" with me - I'd correct one field and it would recalculate (incorrectly) another field. I'd have to erase the fields and start over and ignore the fact that Fuelly was recalculating the number of gallons. I'm using a recent Mac with Safari browser. I just noticed this issue within the last couple of months, but perhaps it has been going on longer than that. I sent a message to technical support and received the following reply:

"Hello and thanks for contacting Fuelly,

Thanks for bringing this to our attention!
We'll have to dig into this, so I do not have an answer or timeline for a fix to offer you at this time.


Robert V- Forums Staff"

I notice your post and response was from almost 4 months ago, so it appears Fuelly hasn't done anything about this problem. Are you still experiencing the issue?
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Old 02-05-2016, 03:28 AM   #4
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There is still something odd with how you enter your data. This morning I added a fillup and it won't let me enter exactly what's on my reciept, and I can't adjust one parameter without the other auto adjusting. For example I can't enter the fuel price without the litres auto adjusting, so my total price is not what's printed on the reciept. Why is that?
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Old 02-05-2016, 05:13 AM   #5
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delete the total cost entry.
it is overriding the other two
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Old 02-05-2016, 05:29 AM   #6
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I received a response from Fuelly on 12/1/15 stating that this should be fixed. I haven't had any problems with the last 8 or 9 fill-ups since then.

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