| ▼ | 1.7 | Case study: nycflights |
| 1.7.1 | The data |
| 1.7.2 | Requiring polars |
| 1.7.3 | Loading the file |
| 1.7.4 | Selecting columns |
| 1.7.5 | Distinct destinations |
| 1.7.6 | Counting and averaging by destination |
| 1.7.7 | Delays into Racket, and a density plot |
| 1.7.8 | Filtering |
| 1.7.9 | The largest delays |
| 1.7.10 | Other separators |
| 1.7.11 | Categorical variables |
| 1.7.12 | Describing strings and datetimes |
| 1.7.13 | Performance |
The scoreboard adds two steps the post leaves out, both where missing values matter. A null delay is not greater than 60, so keeping the flights more than an hour late drops the cancelled ones too (26,581 flights remain on the full file):
> (~> flights (filter (> (col "dep_delay") 60)) height) 572