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--- vd [2021/08/06 13:19] – [Case Study: Exported CSV from PG&E] dblume
+++ vd [2024/05/13 11:23] (current) – [Process Data] dblume
@@ Line 25: / Line 25: @@
 | ; | Extract regex to new column. Ex, ''(video|audio)'', ''(^..)'' or ''(^([STUVW]%%...%%|..))'' |
 | %%^%% | rename the column. Might have to be "product_id" or "platform_id" |
+| = | Use Python function to create new column. Ex, hex to dec: ''int(curcol,16)'' |
+| : | Split column by regex |
 | - | Hide column |
 | S | Go to "Sheets" sheet, to select another sheet to format. |
@@ Line 34: / Line 36: @@
 | " | Open duplicate sheet with only selected rows |
-==== Case Study: Exported CSV from PG&E ====
+===== Inspecting Columnar Data =====
-PG&E CSVs come with 5 rows of metadata followed by Type, Date, Start Time, End Time, Usage, Units, Cost, Notes columns. Delete the five rows of metadata in a text editor, or use ''tail'' to remove them like so:
+^ Key ^ Meaning ^
+| I | Describe all columns, errors, distinct, mode, mean, median, stdev, etc. |
+| i | Add a column of incrementing numbers (useful for '.' charts) |
+| . | Requires an "important" numeric column for row data. Make chart. |
+| O | Options to enable "numeric_binning" and set number of "histogram_bins" (use 'e') |
+| F | Frequency table of row counts, or histogram if numeric_binning is true |
-    tail +6 pge_electric_interval_data.csv | vd -f csv -
+Calculating a percentage-of-total column for a numeric column:
-Then prepare your PG&E data like so:
 ^ Key ^ Meaning ^
-| - | Hide columns TYPE, END TIME, UNITS and NOTES |
+| # | Set column type to "int". |
-| C | Go to column mode and... |
+| I | Describe all columns. (Highlight the "sum" cell for the column of interest.) |
-| t | Select the DATE and START TIME columns |
+| ~ | Convert that column to "text" so it'll be copied correctly for pasting later. |
-| & | Make a new column that merges them |
+| zy | Yank the value of the sum. |
-| q, - | Quit the Column mode, hide DATE and START TIME columns |
+| q | Quit the Describe sheet. |
-| O | Go to options mode and... |
+| = | New column. Enter ''curcol/'', use Ctrl+y to paste the column sum value. |
-| e | Set ''disp_date_fmt'' to ''%Y-%m-%d %H:%M'' |
+====== Case Study Link: Exported CSV from PG&E ======
-| q | Quit options mode. |
-| @!, %, $ | Set DATE_START_TIME to date format and important, USAGE to float, COST to currency |
+Visit [[vd-pge]].
-| = | Add a column, enter ''COST/USAGE'', (Make it float with ''%'') |
-| %%^%% | Rename COST/USAGE to ''kWh cost'' |
+====== Cast Study: Merging Two Tables, logs and metadata ======
-| . or g. | Select columns to graph them. Notice rate changes. Notice times of high use. |
-| +, - | Navigate with hjkl, zoom in and out ([[https://www.visidata.org/docs/graph/|more]]) |
 ==== Protip: Use column view to set multiple columns at once ====
@@ Line 125: / Line 128: @@
   $ 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. |