Start here

Core concepts

Four objects underlie the whole app.

The object model

ObjectDefinition
SourceOne open file or connection. A top-level row in the source browser.
TraceOne signal within a source — a column, an audio channel, a stream field.
TrackOne plotting lane, with its own y-axis, height and name.
Plot itemA trace placed on a track, plus how it is drawn there.
Source one file or connection voltage current temp Traces = the data drag Track one lane, one y-axis voltage line, 1.5px current dashed Plot items = the appearance Rendered
The data is shared; the styling belongs to the plot item.

Traces and plot items

A trace holds the data; a plot item is one appearance of it on one track. The same trace can appear on several tracks with different styling.

Names and colours can be set in two places:

  • On the trace, in the source browser. Renaming also updates any formula that references it.
  • On the plot item, via the coloured dot in a track header. Affects that placement only.

X-axes

Each trace is plotted against a shared x-axis. By default this is the source's row index (0, 1, 2, …), shown as the index row in the browser.

Drag one trace onto another to plot it against the target's values instead. See The x-axis model.

Computed signals

A computed signal is a trace whose values come from a formula over other traces. Computed signals live in a Computed source at the top of the browser, behave like any other trace, and re-evaluate when their inputs change. See Computed signals & formulas.

Viewports

There is one x range for the window: zooming or panning x moves every track together. Each track sets its y range independently.

one x range — shared by every track Track 1 y Track 2 y 0s 10s
One x range, an independent y range per track.

Files and streams

A file source holds everything it parsed. A stream source holds a rolling window — the last N seconds or samples — and older samples fall out of it.

Follow live and the follow-a-signal y mode therefore apply only to streams, and Clear Stream Buffers (⌘K) empties the window without disconnecting. To keep samples beyond the window, enable persistence.