The answers of a matrix field are based on a combination of values in any two other single select fields. Matrix fields have several applications including activity risk assessments, venue risk assessments, equipment or project risk assessments. Matrix allows you to have an alternative risk matrix to the enterprise risk matrix in Folio. Matrix fields are currently available only on Folio Templates.
Creating a Matrix Field
Click on the + New Field button and pick the Field Type Matrix:
If the matrix field is in a table then select the Related Table.
Note: you are able to move the matrix into a table after you have created it.
Next you select the two single select fields you are going to use as the Matrix Rows and Matrix Columns.
In the below example Risk Probability is selected as Matrix Rows and Risk Severity as Matrix Columns.
Then you can add your Matrix field answers and colors. To change the colour, click on the colour dot and choose the colour for that answer. 
After you have selected the Matrix Answers and their colour you can now plot the answers on the matrix at the relevant intersection of the rows and the columns. To do this simply click on the cell and select the matrix answer.
Please Note:
- You will need to have created the two single selects that make up the matrix rows and columns before you start creating the matrix field.
- If the Matrix field is in a Table then the Matrix Rows and the Matrix Columns must also be in the same Table.
- If you change the Matrix then any Folio records already created will not be re-calculated. You will need to edit the records to have the matrix answer reflect the new matrix.
- If the matrix field is in a table then the fields that make up the Matrix Rows and Matrix Columns must be in a table as well.