I am starting with this Hazard Parcel Exposure dataset from the Metropolitan Transportation Commission which I downloaded as a shapefile.
I am using QGIS 3.4.3-Madeira on Mac OS High Sierra 10.13.6.
I tried to convert boolean to numeric values but the values did not calculate all the way through. Why are there blank rows when calculating attributes in QGIS3?
At first I thought maybe there is a selection on, but I did it all again with nothing selected and the same thing happened.
The 5 boolean attributes are shown below.
My goal is to convert each to a numeric value, sum into a new field, and represent each parcel with categorized symbology like so:
Where 0 means no hazards and 5 means there are 5 hazards (all five attributes are True).
First I added temporary fields for each hazard attribute and calculated so it is becomes numerical. This is what I calculated for the first boolean attribute.
The result of calculating that into the field "fltzone" is that True values become 1 and False values become 0. Then I sum all the values into a new field I called hazsum using this calculation:
"fltzone" + "lndstdy" + "liqstdy" + "lndsus" + "liqsus"
The fields calculated and it initially looked like they calculated. But I tried to symbolize it and it looked like this, with many parcels without a numerical hazard exposure value:
When I identify a parcel with a hazsum, it looks great:
But when identifying a neighboring parcel with no hazsum...
I tried to export to Excel and do the calculations there but it kept crashing.
Can you suggest a method to accomplish my goal or to explain why my calculation did not complete?