Differences

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--- vd [2021/06/17 00:18] – dblume
+++ vd [2024/05/13 11:23] (current) – [Process Data] dblume
@@ Line 3: / Line 3: @@
 **[[https://www.visidata.org/|VisiData]]** is an interactive CLI table explorer with vim key bindings. Here is [[https://jsvine.github.io/intro-to-visidata/index.html|a really great tutorial]]. These are notes to myself.
-====== Tips ======
+====== Source Table Recommendations ======
-===== Source Table Recommendations =====
 Gather data with more granularity than you think you need. You often need three tables:
@@ Line 13: / Line 11: @@
   - **Mappings from product ID to product name**: (Maybe from platform ID or from product ID.)
-===== Open VisiData and Set Data Types =====
+====== Open VisiData and Set Data Types ======
   $ vd logs.csv active_devices.csv id_name.csv
-==== Set Column Types, Widths, Names, Importance ====
+===== Set Column Types, Widths, Names, Importance =====
 ^ Key ^ Meaning ^
@@ Line 27: / 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 36: / Line 36: @@
 | " | Open duplicate sheet with only selected rows |
-=== Protip: Use column view to set multiple columns at once ===
+===== Inspecting Columnar Data =====
+^ 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 |
+Calculating a percentage-of-total column for a numeric column:
+^ Key ^ Meaning ^
+| # | Set column type to "int". |
+| I | Describe all columns. (Highlight the "sum" cell for the column of interest.) |
+| ~ | Convert that column to "text" so it'll be copied correctly for pasting later. |
+| zy | Yank the value of the sum. |
+| q | Quit the Describe sheet. |
+| = | New column. Enter ''curcol/'', use Ctrl+y to paste the column sum value. |
+====== Case Study Link: Exported CSV from PG&E ======
+Visit [[vd-pge]].
+====== Cast Study: Merging Two Tables, logs and metadata ======
+==== Protip: Use column view to set multiple columns at once ====
 ^ Key ^ Meaning ^
@@ Line 53: / Line 77: @@
 {{:general:active_devices.png?direct|}}
-===== Join Sheets =====
+====== Join Sheets ======
 Use ''!'' to set Key columns. Use ''F'' (or ''gF'') to remove dupes of Keys by making a Frequency Table.
@@ Line 64: / Line 88: @@
 | gu | Next time you're in Sheets, "global unselect" to unselect the sheets you selected. |
-=== Protip: Remove insignificant noisy rows ===
+==== Protip: Remove insignificant noisy rows ====
 ^ Key ^ Meaning ^
@@ Line 76: / Line 100: @@
 Do a similar thing to join the Joined Sheet with the product Name sheet.
-===== Process Data =====
+====== Process Data ======
 In your final Joined sheet, add rows that are calculations of other rows.
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   $ 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. |