QGIS Choropleth Maps

In this QGIS tutorial we will go over how to create choropleth maps with shapefiles, how to convert a data type, how to join data files (csv) to a shape file, and at the end there is a list of resources to find map layers (shapefiles, etc.).
We go over an example of how to change a data type (from string to integer). In the specific example shown, changing the data type may not be needed however from time to time, changing data types may be necessary. You can change a data type in the source, in a spreadsheet or csv for example, or you can change the data type in QGIS in the attribute table. Also, from time to time when converting data to csv format, the output does not always turn out as expected. A good practice is to view the csv in a text editor such as Atom to make sure the data types, etc. look correct. If the data column that will be used for the choropleth map values comes in as a string, it may need to be converted to a number. For example, if after clicking on Symbology, Graduated, Value, you don't see the value listed, make sure the value is a number and not a string in the attribute table.
You might notice the choropleth map class value range breaks overlap which makes it hard to tell exactly which value range a geographic area fits into. A work around you can try is to uncheck link class boundaries, and double check the value ranges and change them manually. You can also highlight the legend values and change them manually.

[@simonealexander7313]

Thanks for this - the field calculator tip re turning something into an integer was really helpful.

[@harunausman8717]

Thank you so much. This is amazing

[@RyanNoonan]

You're very welcome!

[@user-wq7oe4uh8l]

so much thank you for your video!!!! It's very useful for me, because i'm absolute beginner.. i had to do this for my school project, and i have never done this before, so i'm so hard to do ,, but! I found this video and i could do this more easily!! thanks for thisssssss!!!!1

[@samanthacervantes5943]

thanks so much

[@RyanNoonan]

Welcome

[@h3ctxr]

I'd been struggling with this for a while, my "Graduated" screen still doesn't show the "Column" bar, but instead has one called "Value", I'm guessing this is due to version differences? Still, I was able to get the map working by following the steps here, so thank you so much!

[@guritche]

Yep looks like it was just renamed to 'value'.

[@guritche]

I am having a bit of trouble. I am trying to graduate a column with numbers that I converted to 'real' using your technique. All looks fine until I turn the precision down to -2 to remove the decimals. The numbers round up fine but the Legend column ends up with crazy numbers. For example, for 'Values' 22-23, the 'Legend' column shows 0-0. Values 34-63, Legend shows 0 - 100. This problem doesn't happen when the decimals are showing. Any idea why? TKS!