Live values — the `{astra:value}` role¶

{astra:value} interpolates a real number from the resolved analysis at build time, so no measured value is ever hard-typed into prose. The role body is a path; everything else — which cell, how many digits — is expressed as role options, written inside the curly braces like MyST inline attributes:

{astra:value col=DV_over_rd where="tracer=lrg3_elg1" pm=true}`outputs.bao_distance_table`   → 19.88 ± 0.17
{astra:value col=alpha1 where="tracer=elg1 recon=Pre" sig=3}`outputs.bao_alpha_values`      → 0.0696
{astra:value}`outputs.chi2_reduced`                                                          → 1.5
{astra:value}`decisions.algorithm`                                                           → MultiGrid

Edit astra.yaml or rerun the analysis, rebuild, and every number in the prose updates itself.

Options¶

Option	Meaning
`col=<column>`	The column to read (required for table outputs).
`where="<key>=<val> …"`	Row filters — space- or comma-separated `key=value` pairs; every pair must match, case-insensitively. Alias: `filter=`.
`pm=true`	Also render the uncertainty: `<col>_std` for tables, the metric's own uncertainty for metrics.
`err=<column>`	Explicit uncertainty column (instead of the `<col>_std` convention).
`sig=<N>`	Significant figures for the value (default 4; uncertainties render with 2).

Option values without spaces can be unquoted (col=alpha); quote anything with spaces (where="tracer=lrg3 recon=Post").

Requires a current mystmd

Role options use MyST's inline options syntax, available in current mystmd releases (marked beta upstream). If myst reports an unknown role for {astra:value col=…}` , update the CLI.

Table outputs¶

For a table output MySTRA reads the materialised CSV/JSON result, filters rows by each where= pair, and renders the selected cell:

The LRG3 bin gives $D_V/r_d =$
{astra:value col=DV_over_rd where="tracer=lrg3" pm=true}`outputs.bao_distance_table`.

The filter must select exactly the row you mean — if no row matches, the role renders an inline error naming the filter, so a stale filter is visible in the preview rather than silently wrong.

Metric outputs¶

A metric output — a JSON scalar, a [value, uncertainty] pair, or a {value, uncertainty, unit} object — interpolates its value directly, no options needed. Add pm=true to append the metric's uncertainty when it carries one:

The combined fit gives $\chi^2_\nu =$ {astra:value}`outputs.chi2_reduced`,
with $\alpha =$ {astra:value pm=true}`outputs.alpha_best`.

Decisions¶

A decisions.<id> path renders the label of the option selected under the active universe:

All results use the {astra:value}`decisions.algorithm` reconstruction.

This is subtly different from {astra}`decisions.algorithm`: the plain role names the decision ("Reconstruction algorithm"), while the value role names the selection ("MultiGrid"). Use the value form whenever the prose depends on which option is active — it changes automatically when the universe does.

Errors¶

A value that cannot be resolved — missing result file, unknown column, no matching row, a non-tabular product — renders as a small inline code token describing the problem (e.g. ⟨value: no column "alpha2" in "bao_table"⟩). The page still builds; the broken value is impossible to miss.

Live values — the {astra:value} role¶