Module sampling 

The one sampler every analysis tool reads through: which rows (a scope), how they are picked (a method), how many, and the seed. Describe, Distribution, Correlation and Data Quality all take their rows from read, so a sample means the same thing whichever tool shows it.

Structs

PerValue

What an equal-per-value sample learned beside its rows, from the same pass.

ReadWatch

A read’s line to the screen: told to stop, and telling how many rows it has seen.

Sample

Which rows an analysis reads and how it picks them.

SampleSource

Where a tool’s rows come from before its scope cuts them: the table as shown, or the loaded source with what its footers said. Built on the UI thread; cut in the worker, since preparing a source scan can read its schema.

Enums

Counted

What a streamed pass counted beside its sample.

SampleMethod

How the rows of a scope are picked.

SizeError

Why a typed sample size cannot be read.

Constants

CANCELLED

What a read that was stopped says. Its work is dropped, never shown as a result.

DEFAULT_SAMPLE_ROWS

The default sample size, before [analysis] sample_rows says otherwise.

MAX_COUNTED_KEYS

Distinct keys a pass counts before it gives up counting. Past this the grain is finer than a report can show, and the map would grow with the table.

Functions

no_rows_error

A chosen set of rows that matches nothing is a mistake to say, not an empty sample to analyze: a typed value that is not in the data, a range past its end. The table as shown may simply be empty, and says so itself.

parse_size

A typed sample size: 50000, 50,000, 50_000, 50k, 2m, 2.5M. A size of no rows is refused; past usize it saturates and the caller clamps.

read

Read the rows sample asks for from a frame already cut to its scope.

view_scope_rows

How many rows a view scope holds, from the view’s row count; None for a source scope, whose size only a read can tell.

Type Aliases

HeldJudge

What ReadWatch::hold asks of the bytes a sampler holds and the rows they are.