Select to view content in your preferred language

SQL expression using Boolean Operatiors in Raster Calculator

3778
4
05-20-2016 05:52 AM
MostafaFadhl
New Contributor

Hey guys, Im doing my first Multi Criteria Evaluation and I have to use the Raster Calculator to figure out the optimal placement for wind mills. I followed the setps in my moduel and reclassified the criterion to 1s and 0s - so all I have to do is to use the Raster Calculator and write an expression that finds all the areas with a value of 1. So how does one write such an expression? I used the Boolean AND on two criterion and it worked but it does not work when I use it on all my criterion (I have 5 criterion). Thanks in advance!!

0 Kudos
4 Replies
DanPatterson_Retired
MVP Emeritus

Use Combine—Help | ArcGIS for Desktop you can have up to 20 raster.

However... since you are using a binary classification, I am assuming that you want only those locations where all your classes are 1.  If that is the case, just multiply all the rasters together.

On the other hand if 3 or 4 out of the 5 classes are good, then just add them together.

0 Kudos
MostafaFadhl
New Contributor

Thansk for the reply Dan!

What about the Boolean operators? can they be helpful in this case? According to the assignment I should use the Boolean operators to solve this. Any ideas?

0 Kudos
DanPatterson_Retired
MVP Emeritus

Ahhh, if you read the help, combine is a boolean OR in essence

0 Kudos
curtvprice
MVP Esteemed Contributor

Boolean operators in map algebra (& |) are an implementation of the BooleanAnd and BooleanOr tools, you should look them up in the help for details on how they work with inputs. Given this is homework, I'd check your class notes, they probably will give you a better clue. (We're generally more into answering questions then doing homework around here.) 

Map algebra usually does not involve SQL expressions, that's one of its strengths!