Reshape changes where values live

What operations.reshape is

Reshape operations change the arrangement of values across rows and columns.

They do not join another source or summarize groups by themselves. Pivot may aggregate collisions, but its primary responsibility is layout.

What it contains

• pivot — Turns values from one column into output columns.
• unpivot — Turns several value columns into repeated rows.
• transpose — Exchanges the row and column axes.

Name the identity before moving values

A reshape is understandable when the stable identity is explicit. Read index, id_vars, or index_col first; then follow the values that move around it.

Run the complete example

Copy this manifest from the verified documentation project, then run it from the repository root.

version: "1.0"
transformations:
  steps:
    - unpivot:
        id_vars: [region]
        value_vars: [q1, q2, q3, q4]
        var_name: quarter
        value_name: revenue

hdrctl run examples/tutorial/dsl-elements -s sources-revenue.yaml -t reshape.yaml

  ✅ Pipeline completed successfully in 3.7s
  Rows read   : 5
  Rows written: 20

The relevant command syntax, copied from hdrctl run --help:

hdrctl run [PATH]
  -s, --sources FILE          explicit path to sources.yaml
  -d, --destinations FILE     explicit path to destinations.yaml
  -t, --transformations FILE  explicit path to transformations.yaml
  -P, --param KEY=VALUE       override a parameter, repeatable

Close by

• Aggregate — changing grain
• Columns — changing contract
• steps — execution order
• Combine — adding another frame
• Reference — pivot, unpivot, transpose