Step 2: Defining Categories (Python)

There are two ways to define categories for each dimension: explicitly, using the SetCategories method, or implicitly when setting values. The explicit method is shown here. The implicit method is shown in Step 3: Setting Cell Values (Python).

Example

from spss import CellText
table = spss.BasePivotTable("Table Title",
                            "OMS table subtype")

coldim=table.Append(spss.Dimension.Place.column,"coldim")
rowdim1=table.Append(spss.Dimension.Place.row,"rowdim-1")
rowdim2=table.Append(spss.Dimension.Place.row,"rowdim-2")

cat1=CellText.String("A1")
cat2=CellText.String("B1")
cat3=CellText.String("A2")
cat4=CellText.String("B2")
cat5=CellText.String("C")
cat6=CellText.String("D")
cat7=CellText.String("E")

table.SetCategories(rowdim1,[cat1,cat2])
table.SetCategories(rowdim2,[cat3,cat4])
table.SetCategories(coldim,[cat5,cat6,cat7])
  • The statement from spss import CellText allows you to omit the spss prefix when specifying CellText objects (discussed below), once you have imported the spss module.
  • You set categories after you add dimensions, so the SetCategories method calls follow the Append or Insert method calls.
  • The first argument to SetCategories is an object reference to the dimension for which the categories are being defined. This underscores the need to save references to the dimensions you create with Append or Insert, as discussed in the previous topic.
  • The second argument to SetCategories is a single category or a sequence of unique category values, each expressed as a CellText object (one of CellText.Number, CellText.String, CellText.VarName, or CellText.VarValue). When you specify a category as a variable name or variable value, pivot table display options such as display variable labels or display value labels are honored. In the present example, we use string objects whose single argument is the string specifying the category.
  • It is a good practice to assign variables to the CellText objects representing the category names, since each category will often need to be referenced more than once when setting cell values.
Figure 1. Resulting table structure
Resulting table structure

Note: Generation of the resulting table requires more code than is shown here.