Search-report.pdf

The Search-report.pdf file is meant to collate the overall progress of the current optimization, stretching over multiple searches. If only one search is performed, it is mostly redundant with the Search-progress.pdf file.

R-factor / Generations

The \(R\) factor is plotted over the total number of generations, similar as in the Search-progress.pdf file. Vertical lines indicate the transition from one search to the next, and which search is being performed is labelled at the top of the plot. As in Search-progress.pdf, the black line represents the \(R\) factor of the best-fit structure, the grey area is the range between the best and worst \(R\) factor, and the blue line is the average \(R\) factor of the entire population. Both the range and the average can and do often increase when the next search begins.

Parameter scatter / Generations

The x-axis is shared with the \(R\)-factor plot above. This plot is supposed to give a measure of how well a given search has converged. The ‘parameter scatter’ being drawn is defined as the standard deviation of parameter positions in the parameter scatter plots below, where each displacement range is normalized to the interval [0, 1]. The black line indicates the standard deviation for the most scattered parameter, i.e., the least well-defined or well-converged parameter. The blue line tracks the mean of those standard deviations. If the black line reaches zero, then this means that the entire population has converged to the same values for every parameter.

Parameter scatter plots

The parameter scatter plots in the Search-report.pdf file are direct copies of the latest such plots in the Search-progress.pdf files. If a search is performed in a loop, only the latest iteration of the loop is found in the Search-report.pdf file.

Example

Below are is an example of a Search-report.pdf file that was generated a structural optimization discussed in the example calculation discussed here.

Fig. 27 Example of the first page of a Search-report.pdf file. The upper plot shows the \(R\) factor over generations, the lower plot shows the number of generations since the last improvement.

Fig. 28 Example of the second page of a Search-report.pdf file showing the parameter scatter plots. The upper three lines show z-displacements, the lowest line shows changes in vibrational amplitude.