7 Replies Latest reply on Jan 6, 2014 9:26 AM by Jerry Tweedy

latitude and longitude truncating to a general location

Jerry Tweedy Dec 30, 2013 8:32 AM

I have imported a data source with latitude and longitude formatted in a decimal format to 5 decimal places. When plotting the points on a map it is truncating the longitude values to three digits thereby creating what is essentially columns of points on the map. I've changed the aggregation to average as well as tried moving the measures to a dimension. I suspect I am doing something wrong I am just unsure what this is.

Sample Lat and Long Data.twbx 587.9 KB

1. Re: latitude and longitude truncating to a general location

Dan Cory Jan 2, 2014 5:35 PM (in response to Jerry Tweedy)

It's hard to say what the problem is. Can you post the original Excel file as well? Or the file you imported into Excel if any?

My impression is that in fact Tableau is showing all the precision that is in your data, but there's some problem or limitation further upstream.

Dan
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2. Re: latitude and longitude truncating to a general location

Ville Tyrväinen Jan 2, 2014 6:27 PM (in response to Dan Cory)

I also looked that workbook and I would say that problem is with original data, if there is a problem at all ...

Ville
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3. Re: latitude and longitude truncating to a general location

Jerry Tweedy Jan 3, 2014 6:39 AM (in response to Dan Cory)
Attached is the original MS Excel data sheet. I've tried importing this into Tableau 8 and Tableau 8.1.

Sample Lat Long Data.xlsx 14.1 MB
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4. Re: Re: latitude and longitude truncating to a general location

Dan Cory Jan 3, 2014 9:37 AM (in response to Jerry Tweedy)
The problem is that the decimal latitudes and longitudes here are wrong - they do not match the degrees/minutes/seconds latitudes and longitudes. When I reconverted those, the map looks much more reasonable. File attached.

It looks like the data originally came from Access. Perhaps it was messed up there.

Corrected Lat Long.twbx 14.9 MB
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5. Re: latitude and longitude truncating to a general location

Jerry Tweedy Jan 6, 2014 8:59 AM (in response to Dan Cory)

Thanks for the data fix. What tool or formula did you use to convert from degrees, minutes, seconds to decimal format? Thanks again for the help.
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6. Re: latitude and longitude truncating to a general location

Dan Cory Jan 6, 2014 9:16 AM (in response to Jerry Tweedy)

I used Excel to parse out the columns, then degrees + minutes/60 + seconds/3600. It's possible to do this directly in Tableau but the parsing is a bit messier.
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7. Re: latitude and longitude truncating to a general location

Jerry Tweedy Jan 6, 2014 9:26 AM (in response to Dan Cory)

I see my error, I divided the seconds by 360 and not 3600. Thanks again.
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