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The "locomotor drive potential" amplitude on the waveform selected by the "Amplitude W.F. #" is plotted with respect to the duration of cycles on the waveform selected by the "Cycle W.F. #". A point is plotted for each complete cycle. The L.D.P. for each cycle is calculated as the difference between the minimum and maximum levels measured on the former waveform. The parameters "W.F. amplitude delay" and "W.F. amplitude window" indicate a range of points, relative to the highest or lowest point in the cycle, used to obtain an average level reading for the maximum or minimum part of the cycle. The parameters "Min W.F. amplitude" and "Max W.F. amplitude" can restrict the voltage levels allowed in the analysis to a smaller range.
If the "Preview averaged data" option is enabled, the calculated minimum and maximum levels are displayed as markers on the waveform. You can use the cursor to move the markers to the levels you desire, to correct the L.D.P. calculation. When you exit the preview display, the complete graph is shown. If this option is set, and you are repeating the "Go" operation when the graph does not need to be recalculated, the program will ask you if you want to recalculate it anyway, and if not, whether you want to review the calculated levels.
The top title lines of the graph will show a few calculated statistics: the mean L.D.P., trough & peak (min. & max. amplitude). If the alternate unit specifier for the displayed waveform is mmHg, it is assumed that the signal is blood pressure, and in this case the mean arterial pressure is also shown, calculated as 1/3 of the peak plus 2/3 of the trough. If the "Display std dev" option is enabled, another top title line will show the standard deviation calculations for these means.
If the "Show time on X-axis" option is enabled, the usual X-axis is overridden by the cycle start times. In other words, the graph becomes one of L.D.P. amplitude versus time of cycle occurrence in the run.
If the "Flip L.D.P. and duration" option is enabled, the usual X and Y axes are transposed, giving you a graph of cycle duration versus L.D.P. amplitude. If the "Flip L.D.P. and duration" option and the "Show time on X-axis" option are both enabled, the graph becomes one of cycle duration versus time of cycle occurrence.