concatenate_gradients

pypulseqpp.concatenate_gradients()

Concatenate gradients on one channel without modifying the inputs.

Skip None entries. The first gradient keeps its delay; subsequent gradients start when the preceding gradient ends.

Parameters:

• *grads (GradEvent or TrapEvent or None) – Gradients on the same channel, in play order. None is skipped.

• system (pypulseqpp.Opts, default=None) – System limits.

Returns:

The gradients concatenated into a single event, or the sole gradient unchanged when only one is given.

Return type:

GradEvent

Raises:

ValueError – If no gradient is given, or they are not all on one channel.

Examples

>>> import pypulseqpp as pp
>>> system = pp.Opts()
>>> select = pp.make_trapezoid("z", area=200.0, duration=2e-3, system=system)
>>> rephase = pp.make_trapezoid("z", area=-100.0, duration=1e-3, system=system)
>>> merged = pp.concatenate_gradients(select, rephase, system=system)
>>> round(pp.calc_duration(merged), 6) == round(
...     pp.calc_duration(select) + pp.calc_duration(rephase), 6
... )
True

The inputs keep their own delays:

>>> float(rephase.delay)
0.0