The waveform parameter under the display parameters in the working parameter file determines whether the simulated waveforms are to be viewed on-line. If the waveform parameter is assigned the numerical value of -1, then the waveforms are not displayed as they are being calculated but may be subsequently viewed and analyzed off-line. The researcher may choose this option, if, for example, the data required for analysis are very time consuming to generate (e.g., Monte Carlo simulations). If the waveform parameter is assigned one or more numerical values between 0 and 28 inclusive (with a single space inserted between each assigned numerical value), then the waveforms corresponding to those numerical values (see the $DIR/pararmeters.def file (Figure 9) or the generated file with extension .hea for mapping key between waveforms and numerical values) will be displayed as they are being calculated. For example, in Figure 9, the waveform parameter is set such that left ventricle and systemic arterial pressures will be displayed on-line. Note that the annotations parameter beneath the waveform parameter is simply a flag indicating whether the contents of the annotations file, which include the times of onset of ventricular contractions and parameter updates, will be viewed on-line with the waveforms selected by the waveform parameter. Note that if the waveform parameter is set to the numerical value of -1, then the contents of the annotations file will not be displayed on-line regardless of the value assigned to the annotations parameter.
The rcvsim executable file implements on-line viewing by periodically updating the WAVE display with the most recently computed window of waveforms. The time duration of the window and the update time period (both simulation times) may be respectively set to desired values with the window and step parameters. For optimal on-line viewing, the window parameter should be set equal to the time duration displayed by WAVE. This latter time duration is set by the physical size of the WAVE window as well as the Time scale variable which is essentially a calibration factor mapping this physical size to time duration. The Time scale variable may be altered by clicking the VIEW option on the WAVE menu bar. The step parameter should be chosen to be sufficiently small such that the displayed waveforms appear to scroll continuously through the WAVE window. However, if the step parameter is chosen to be too small, then the actual time required to update the display of the simulated data may not be sufficient and the quality of viewing may thus be compromised.