which-function.md

Which function do I need?

Find your task, then follow the link for the details. Every function is in the lbd reference or the lbd.plot reference. Whole scripts, from data to figure, are in the Examples.

import lbd                # files
import lbd.plot as lp     # figures (pip install "lbd[plot]")

Save and read data

I want to…	Use	Example
save a measurement	[Dataset][lbd.Dataset], [add_axis][lbd.Dataset.add_axis], [add_value][lbd.Dataset.add_value], [save][lbd.Dataset.save]	Building a dataset
read a file	[lbd.load][lbd.load]	d = lbd.load("sweep.lbd")
read only some values of a big file	[lbd.load][lbd.load] with values=	lbd.load("big.lbd", values="S21")
list or check many files quickly	[lbd.info][lbd.info]	Reading
give files a default plot without rewriting them	[lbd.set_plot][lbd.set_plot]	lbd.set_plot(p, spec={"kind": "heatmap"})
know which version is installed	[lbd.version][lbd.version]	lbd.version()

Plot data like the viewer

I have…	Use	Example
an .lbd file	[lp.plot][lbd.plot.plot]	lp.plot("sweep.lbd")
a Dataset in memory (saved or not)	[lp.plot][lbd.plot.plot]	lp.plot(d, "heatmap", "S21", complex="db")
plain arrays	[lp.quick][lbd.plot.quick]	lp.quick(t, v, x_unit="s", y_unit="V")
a figure with several panels	[lp.plot][lbd.plot.plot] with ax=	Panels

Make my own figures match

I want to…	Use	Example
style a figure I draw with matplotlib	[lp.use][lbd.plot.use]	with lp.use("thesis"): fig, ax = plt.subplots()
style every figure in a notebook	[lp.activate][lbd.plot.activate]	lp.activate("thesis")
another size, or a grid of axes	[lp.subplots][lbd.plot.subplots]	lp.subplots(1, 2, width_mm=170)
restyle a figure made by other code	[lp.apply][lbd.plot.apply]	lp.apply(fig, "thesis")
readable units (7e9 Hz → 7 GHz) or a fixed prefix	[lp.prefix][lbd.plot.prefix]	f, unit = lp.prefix(f, "Hz", to="M")
an axis title with its unit	[lp.axis_label][lbd.plot.axis_label]	lp.axis_label("Frequency", unit)
save exactly like the viewer exports	[lp.save][lbd.plot.save]	lp.save(fig, "fig.pdf", style="thesis")

Work with styles

I want to…	Use	Example
see the preset names	[lp.list_styles][lbd.plot.list_styles]	lp.list_styles()
read or change settings in Python	[lp.load_style][lbd.plot.load_style]	s = lp.load_style("thesis"); s.figure.width_mm
keep a style next to a paper's data	[Style.save][lbd.plot.style.Style.save]	lp.load_style("thesis").save("thesis.lbd.json")
give a style to someone without LBD	[Style.to_mplstyle][lbd.plot.style.Style.to_mplstyle]	mplstyle recipe
create, change or delete a preset	[PresetStore][lbd.plot.PresetStore]	lp.PresetStore().save("paper", {...})
the exact style the viewer uses for a file	[PresetStore.resolve][lbd.plot.PresetStore.resolve]	see its example

When something goes wrong

Functions raise an error when they can't do what was asked (the message names the problem and the valid choices) and give a warning when they did it but ignored or adjusted something. Nothing is dropped silently. See Errors and warnings.