SequencePlugin

class pulserver.design.SequencePlugin

Bases: object

A sequence function bound to the entries of the scanner protocol.

A subclass sets app and, for the arguments the operator edits, protocol; without protocol the sequence function plays its defaults. Entries a request omits keep their initial values, the entry’s default or else the sequence function’s. Times travel as integer microseconds and other floats to six significant digits, the precision of a float32 parameter, so a reply stored in scanner parameters and sent back evaluates to itself.

validate() evaluates a request with evaluate(), and design() generates and writes it with generate(). A subclass overrides the hooks evaluate() and generate(), and does not override validate() or design().

Attributes:

• app (callable) – The sequence function, app(system, **arguments). It takes the scanner limits, a pypulseqpp.Opts, and the keyword arguments the entries of protocol bind, and returns a pypulseqpp.Sequence or a list of them, which is a chain: the prescans first and the main sequence last. The defaults the listing shows are those of its signature, so a functools.partial() is a sequence function too. generate() calls it, and so does an evaluate() that designs the sequence; the default evaluate() does not.

• protocol (mapping) – The entries the operator edits, by key: the interpreter’s parameter names, which are the members of ProtocolKey that UIParam collects. A plain string naming an entry is stored as its member. Empty by default. An entry that states its default may bind a name the app does not take; it is then read by the plugin’s own evaluate() and generate(), which do not pass it to the app.

Raises:

• ValueError – When a subclass is defined with a protocol key the interpreter does not know, which its parser would drop, or with one of the prescription entries, which pulserver applies itself; or with both protocol and ui.

• TypeError – When a subclass is defined with a class as app.

Warns:

DeprecationWarning – When a subclass sets recon, which has no effect: the reconstruction is named by the reconstruction client or, on a console, by the scan. When a subclass sets follows, which has no effect: the RF a scanner scales is the RfLayout an evaluation returns. When a subclass sets ui, the deprecated name of protocol, or subclasses ScannerSequence, the deprecated name of this class.

Methods

design	Write the sequence of a request into directory as signed binary Pulseq.
evaluate	Evaluate a requested protocol, or refuse it by raising.
generate	Return what design() writes for a protocol.
listing	Return the protocol with its schema, valued at the sequence function's defaults.
validate	Return the validation of a request, as the wire carries it.

Attributes

protocol
reads_exam	Whether evaluate() or generate() takes exam.
app