Electric Eel Waveform Analyzer generates quantitative data summarizing the geometrical structure of EOD waveforms. Waveforms are subdivided into Homologous Segments
. The duration, amplitude and area of each segment are then calculated. The following steps are involved:1. Each waveform is divided into 1 – 5 homologous Phases, with P1 being the dominant positive phase. Phases preceding P1 are labeled P0 and P-1 from right to left. Phases following P1 are labeled P2 through P4 from left to right. Phases are separated by Zero Crossovers and by the Start and End of the EOD.
2. Each phase is divided into an ascending and descending limb at the Peak Amplitude.
3. Each limb is divided into two sections at the position of the maximum slope gradient (corresponding to the maximum Derivative value). Hence, a monophasic EOD is divided into 4 sections, a biphasic EOD into 8 sections, and a 6-phase EOD into 24 sections.
4. The following information is computed for each of the 4 – 24 Segments described above. The full data set for a waveform can be exported to Excel (see File - Save Peak Information).
i. Start and end amplitude measured
in arbitrary units.
ii. Start and end time: Durations and Timings are measured from real Sample
Points (for automatically selected peaks and positions of maximum
derivatives) or from interpolated positions between real points (for duration
cut-off thresholds and manually selected peaks). Interpolation of duration
cut-off thresholds is based on Triangulation
Interpolation .Interpolation of manually selected peaks is based
on Cubic Spline Interpolation.
iii. Area – calculated by the integration of amplitude and duration.
5. Options: i. minimum
peak % setting (Options - Set Constants) controls which phases are
Valid Phases. ii. Do
not use Zero Crossovers for Durations (Options - General Preferences)
determines whether the beginning and end of all phases of an EOD waveform (except
beginning of first phase and end of last phase) are measured at the Duration
Cut-off % or at the Zero
Crossovers. iii. Duration
Cut-off % (Options: Set Constants) controls the cut-off % for duration
thresholds. iv. Duration Cut-off
% Calculated as % of:(Options: Set Constants) selects reference for
duration cut-off % (% of each peak, P1,
P1+P2, Peak-to-Peak Amplitude).