Differences

This shows you the differences between two versions of the page.

--- vd [2023/05/17 14:00] – [Inspecting Columnar Data] dblume
+++ vd [2026/01/14 13:03] (current) – [Calculating a percentage column for only specific columns] dblume
@@ Line 45: / Line 45: @@
 | F | Frequency table of row counts, or histogram if numeric_binning is true |
-Calculating a percentage-of-total column for a numeric column:
+====== Adding Percentage Columns ======
+===== Calculating a percentage-of-global-total column =====
 ^ Key ^ Meaning ^
@@ Line 54: / Line 56: @@
 | q | Quit the Describe sheet. |
 | = | New column. Enter ''curcol/'', use Ctrl+y to paste the column sum value. |
+===== Calculating a percentage column for only specific columns =====
+Say you've got a sheet with Date, Platform, Features, More, and Counts, and
+you want a Counts percentage of just the first two columns.
+This will require joining two sheets.
+^ Key ^ Meaning ^
+|         | **First, make the subtotals for the first sheet...** |
+| @ # ! - | Set column types, important columns, and hide unused columns |
+| + sum   | Set aggregator to sum for the subtotal column |
+| gF      | Make the frequency table. These sums will be the **dividend**. |
+|         | **Get rid of the new counts column, remove importance of column for next percentage.** |
+| ! - + sum | Remove importance, hide unused "counts" column, set aggregator of _sum column. |
+| gF      | Make another Frequency table. These sums will be the **divisor**. |
+|         | **Join the two Frequency tables.** |
+| S t t & inner | Join the two tables from the Sheets sheet. |
+| =Counts_sum*100.0/Counts_sum_sum | Make the new percentage column. |
 ====== Case Study Link: Exported CSV from PG&E ======
@@ Line 128: / Line 149: @@
   $ vd --play=my_cmdlog.vd --replay-wait=0.5
+====== Lists in Cells for Frequency Tables ======
+Sometimes you want one of the columns in a Frequency Table to be a list of unique values. Let's say the column title is "my_column", then:
+^ Key ^ Meaning ^
+| + | Set the aggregator to "List" |
+| F | Make a Frequency Table for the selected column. (gF for selected columns) |
+| =, ','.join(set(my_column)) | Create a new column of a comma delimited Python Set of cell entries. |