Import heavy third-party modules lazily (matplotlib, numpy, cv2)#110
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Problem: Importing anything from hardwarelibrary.spectrometers eagerly loaded matplotlib and numpy. base.py did `from .viewer import *` (viewer is a pure matplotlib GUI module) purely to reach SpectraViewer, and imported numpy at module scope. oceaninsight.py imported matplotlib (backends/pyplot/animation/Button/TextBox) that it never actually used, plus numpy at module scope. __init__.py imported SpectraViewer at the top. As a result `import hardwarelibrary` paid the full matplotlib + numpy cost even when no plot was ever drawn. Solution: Move the heavy imports to their point of use. SpectraViewer is now imported inside Spectrometer.display(), OISpectrometer.display() and displayAny(). numpy is imported inside the __init__/getSpectrum methods that use it; base.py gains `from __future__ import annotations` so the `-> np.array` hint no longer forces numpy at class-definition time. The dead matplotlib import block in oceaninsight.py (never referenced) is removed. viewer.py is unchanged: it legitimately needs matplotlib, and is now only imported when a viewer is actually shown. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Problem: oscilloscopedevice.py imported matplotlib.pyplot at module scope, so `import hardwarelibrary` (which imports the oscilloscope package) loaded matplotlib even though plt is only ever used by the optional displayWaveforms() method. Solution: Move `import matplotlib.pyplot as plt` into displayWaveforms(), its only caller. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Problem: camera.py imported cv2 at module scope behind a try/except. Importing the cameras package therefore loaded OpenCV eagerly, and a missing OpenCV only surfaced as a printed warning at import time while leaving cv2 undefined for later calls. Solution: Remove the top-level guarded import and import cv2 inside the three methods that use it (captureLoopSynchronous, openCVProperties, doInitializeDevice). The module now imports without OpenCV present, and a missing dependency surfaces as a clear ModuleNotFoundError only when a camera operation is actually invoked. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Problem: sutterdevice.py and echodevice.py both did `from pyftdi.ftdi import Ftdi`, each already flagged with a `#FIXME: should not be here.` comment. Neither file references Ftdi anywhere, so the imports were dead code that pulled pyftdi in eagerly. Solution: Delete the unused imports. SutterDevice reaches FTDI hardware through SerialPort, which owns the pyftdi dependency. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Problem
import hardwarelibraryeagerly loadedmatplotlibandnumpythrough the spectrometer and oscilloscope packages, even when nothing was ever plotted or acquired. Several imports were also dead:oceaninsight.pyimported matplotlib it never used, andSutterDevice/EchoDeviceimportedpyftdi.Ftdithey never referenced (both already flagged#FIXME: should not be here).Solution
Defer each non-standard module to its point of use, and delete the dead imports:
010ab73):SpectraViewernow imported insidedisplay()/displayAny();numpyinside the__init__/getSpectrummethods that use it;base.pygainsfrom __future__ import annotationsso the-> np.arrayhint no longer forces numpy at class-definition time. Removed the unused matplotlib import block inoceaninsight.py.viewer.pyis unchanged — it legitimately needs matplotlib and is now only imported when a viewer is shown.ffb1457):matplotlib.pyplotmoved intodisplayWaveforms(), its only caller.ba2a102): removed the top-level guardedimport cv2; deferred into the three methods that use it. A missing OpenCV now surfaces as a clearModuleNotFoundErroronly when a camera op is invoked, instead of a print at import time.6013246): removed unusedfrom pyftdi.ftdi import FtdifromSutterDeviceandEchoDevice.Result
import hardwarelibrary: 336 ms -> 59 ms, withmatplotlibandnumpyno longer loaded until you actually plot or acquire.Reviewed and left as-is
pyftdiincommunication/serialport.py— genuinely used across several methods, ~10 ms to import, core serial dependency.pyserial/pyusb— lightweight core comms deps, used pervasively.u3(LabJack) indaq/labjackdevice.py— not on the default import path.pylablibinmotion/thorlabs.py— already lazily imported.Testing
Full suite: 398 passed, 235 skipped (hardware-absent), unchanged from baseline.
Deferred paths exercised directly:
DebugSpectro.getSpectrum()(numpy), oscilloscope + cameras imports without matplotlib/cv2 loaded.🤖 Generated with Claude Code