EXAMPLE - SUMIF and COUNTDISTINCTIF Functions
This example illustrates how you can use conditional calculation functions.
Functions:
Item | Description |
|---|---|
SUMIF Function | Generates the sum of rows in each group that meet a specific condition. |
COUNTDISTINCTIF Function | Generates the count of distinct non-null values for rows in each group that meet a specific condition. |
Source:
Here is some example polling data across 16 precincts in 8 cities across 4 counties, where registrations have been invalidated at the polling station, preventing voters from voting. Precincts where this issue has occurred previously have been added to a watch list (precinctWatchList).
totalReg | invalidReg | precinctWatchList | precinctId | cityId | countyId |
|---|---|---|---|---|---|
731 | 24 | y | 1 | 1 | 1 |
743 | 29 | y | 2 | 1 | 1 |
874 | 0 | 3 | 2 | 1 | |
983 | 0 | 4 | 2 | 1 | |
622 | 29 | 5 | 3 | 2 | |
693 | 0 | 6 | 3 | 2 | |
775 | 37 | y | 7 | 4 | 2 |
1025 | 49 | y | 8 | 4 | 2 |
787 | 13 | 9 | 5 | 3 | |
342 | 0 | 10 | 5 | 3 | |
342 | 39 | y | 11 | 6 | 3 |
387 | 28 | y | 12 | 6 | 3 |
582 | 59 | 13 | 7 | 4 | |
244 | 0 | 14 | 7 | 4 | |
940 | 6 | y | 15 | 8 | 4 |
901 | 4 | y | 16 | 8 | 4 |
Transformation:
First, you want to sum up the invalid registrations (invalidReg) for precincts that are already on the watchlist (precinctWatchList = y). These sums are grouped by city, which can span multiple precincts:
Transformation Name |
|
|---|---|
Parameter: Formula type | Single row formula |
Parameter: Formula | SUMIF(invalidReg, precinctWatchList == "y") |
Parameter: Group rows by | cityId |
Parameter: New column name | 'invalidRegbyCityId' |
The invalidRegbyCityId column contains invalid registrations across the entire city.
Now, at the county level, you want to identify the number of precincts that were on the watch list and were part of a city-wide registration problem.
In the following step, the number of cities in each count are counted where invalid registrations within a city is greater than 60.
This step creates a pivot aggregation.
Transformation Name |
|
|---|---|
Parameter: Row labels | countyId |
Parameter: Values | COUNTDISTINCTIF(precinctId, invalidRegbyCityId > 60) |
Parameter: Max number of columns to create | 1 |
Results:
countyId | countdistinctif_precinctId |
|---|---|
1 | 0 |
2 | 2 |
3 | 2 |
4 | 0 |
The voting officials in counties 2 and 3 should investigate their precinct registration issues.