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<div class="moz-cite-prefix">On 11/05/2012 06:42 PM, Ramon Andiñach
wrote:<br>
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<blockquote
cite="mid:FE271851-22C0-44CF-A880-5525025E7C28@westnet.com.au"
type="cite">
<pre wrap="">Hi Lee,
I don't have an answer, but I have seen similar things if I've been editing the strings and then go into the attribute table without saving first.
Is it possible to post a bit of your shape file somewhere for those that know what they're doing to look at? This may help.
-ramon.</pre>
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US Census data:<br>
Download page:
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charset=ISO-8859-1">
<a href="http://www.census.gov/geo/maps-data/data/tiger-data.html">http://www.census.gov/geo/maps-data/data/tiger-data.html</a><br>
Direct download of specific shapefile:
<a class="moz-txt-link-freetext" href="http://www2.census.gov/geo/tiger/TIGER2010DP1/State_2010Census_DP1.zip">http://www2.census.gov/geo/tiger/TIGER2010DP1/State_2010Census_DP1.zip</a><br>
<br>
The operation I was doing is turning the age 65 count into a
percentage with the following formula:<br>
<br>
100.0 * "DP0070001" / "DP0010001"<br>
<br>
The reason for the 100.0 is to force the field calculator to do a
floating point operation. Otherwise, integer division causes the
outcome to always be 0.<br>
<br>
Would be curious if others can reproduce, since I no longer can.
Basically, use field calculator to create the new field and
calculate value at the same time, then try to save the result.<br>
<br>
If the field precision is set high (not sure of the exact cutoff)
QGIS creates the field as a double instead of real. I thought this
might be contributing to the problem, but at this point it seems to
be working whether the field is created as double or real.<br>
<br>
--Lee<br>
<br>
<pre class="moz-signature" cols="72">--
Lee Hachadoorian
Assistant Professor in Geography, Dartmouth College
<a class="moz-txt-link-freetext" href="http://freecity.commons.gc.cuny.edu">http://freecity.commons.gc.cuny.edu</a>
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