grind op• Data kinds: signal × scalar → table
• Call: import fullseye as fs; fs.ledger.ae_band_power(x, rate: 'float', f_lo: 'float' = 100000.0, f_hi: 'float' = 1000000.0, start: 'int' = 0, stop: 'int | None' = None, win: 'int' = 4096) -> 'dict' (to call the implementation directly, import grind; grind.ae_band_power(x, rate: 'float', f_lo: 'float' = 100000.0, f_hi: 'float' = 1000000.0, start: 'int' = 0, stop: 'int | None' = None, win: 'int' = 4096) -> 'dict'; from the registry, opsdrive.get("ae_band_power"))
Computes the AE band power in 2 ways (one with the definition from the published analysis code, the other from the density spectrum of acoustics.stft).
• power_fft: the square of the unwindowed FFT amplitude 2|X|/N summed over f_lo ≤ f ≤ f_hi [V²] (same as the analysis code; for a sine of amplitude A this is A²).
• power_stft: the mean over inner frames of the PSD from acoustics.stft(scaling="density") integrated over the band [V²] (= band mean square). By Parseval power_fft ≈ 2 · power_stft (amplitude² is twice the mean square). Returns the ratio ratio = power_fft / (2 power_stft).
• band_series / times: per-frame band power (time evolution of the spectrogram band); spectrogram_db is for display (full band regardless of the band).
start / stop slice the samples (the analysis code starts at 200013 to skip the noise segment).
• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).
• Operator provenance and references — the sources of the research/methods this op family came from.
• The canonical algorithm (author, year) and its uses are named in the family usage guide above.
• poc_powder_grinding_ae — py -3.11 examples/poc_powder_grinding_ae.py
table as input)course_layout · course_occupancy · course_contains · world_build · world_camera · world_move · lidar_scan · rss_longitudinal_same
grind)particle_size_read · particle_size_dx · particle_size_oversize · particle_size_synth · comminution_energy · comminution_law_fit · breakage_first_order_fit · replicate_compare
*Provenance: grind.py — DRIVE operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.