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@(@\newcommand{\B}[1]{ {\bf #1} } \newcommand{\R}[1]{ {\rm #1} } \newcommand{\W}[1]{ \; #1 \; }@)@This is dismod_at-20221105 documentation: Here is a link to its current documentation .
Perturb Command: Random Change to Start or Scale Tables

Syntax
     As Program
     As Python Function
database
tbl_name
     scale_var
     start_var
sigma
     Random Seed

Syntax

As Program
dismodat.py database perturb tbl_name sigma

As Python Function
dismod_at.perturb_command(database, tbl_name, sigma)

database
is the path from the currently directory to the database. This must be a dismod_at and the init_command must have been run on the database.

tbl_name
This is the name of an input table that we are perturbing. This must be one of the following choices:

scale_var
In this case the scale_var_table is perturbed. This can be useful when one starts near the solution where the derivative of the objective may be small.

start_var
In this case the start_var_table is perturbed. This can be useful when one wants to see if the starting point has an effect on the solution.

sigma
We use multiplier for a randomly chose multiplier, that is different for each table entry, and that has a log with mean zero and standard deviation sigma . The value chosen for each table entry is its original value times the multiplier. If this value is below (above) the lower (upper) limit for the table entry the lower (upper) limit is chosen.

Random Seed
If the random_seed is non-zero, it is used to seed the random number generator that is used. Otherwise, the system clock is used to seed the random number generator.
Input File: python/dismod_at/perturb_command.py