Documentation/UserGuide/PDF Files

Contain a pdf (probability distribution function) of selected variables as a formatted table (essentially a .tab file). A variety of statistics are computed, including the mean and variance of the distribution, the average and standard deviation, and the skewness and kurtosis of the distribution.

A new sequentially numbered file is created whenever the integration time exceeds an integer multiple of <output>/dt. At the end of execution, the lesser of tlim/dt or <time>/nlim sequentially numbered files will be created. Also writes a history-type file with name prb_stat.id, where id is the string identifier for this output, with each row in the file containing statistics of each .pdf output.

This is a specialized format that is useful only for some problems, where the statistics of fluctuations in some variable is important (for example, 3D turbulence).

An example of an <output> block which creates a pdf of the density is given below.

<output2>
out_fmt = pdf                # Binary data dump
out     = d                  # density
id      = d                  # string identifier
dt      = 1.0                # time increment between outputs


Created by the function output_pdf.c; this function should be studied carefully to understand more about this format and what information it contains.