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Checkpoint for SumStats rename.

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This commit is contained in:
Seth Hall 2013-04-15 15:12:28 -04:00
parent 8165d6077d
commit fbe967e16a
32 changed files with 626 additions and 620 deletions
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69
scripts/base/frameworks/sumstats/plugins/variance.bro Normal file
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@load ./average
@load base/frameworks/sumstats
module SumStats;
export {
redef enum Calculation += {
## Find the variance of the values.
VARIANCE
};
redef record ResultVal += {
## For numeric data, this calculates the variance.
variance: double &optional;
};
}
redef record ResultVal += {
# Internal use only. Used for incrementally calculating variance.
prev_avg: double &optional;
# Internal use only. For calculating incremental variance.
var_s: double &default=0.0;
};
function calc_variance(rv: ResultVal)
{
rv$variance = (rv$num > 1) ? rv$var_s/(rv$num-1) : 0.0;
}
# Reduced priority since this depends on the average
hook add_to_reducer_hook(r: Reducer, val: double, data: Observation, rv: ResultVal) &priority=-5
{
if ( VARIANCE in r$apply )
{
if ( rv$num > 1 )
rv$var_s += ((val - rv$prev_avg) * (val - rv$average));
calc_variance(rv);
rv$prev_avg = rv$average;
}
}
# Reduced priority since this depends on the average
hook compose_resultvals_hook(result: ResultVal, rv1: ResultVal, rv2: ResultVal) &priority=-5
{
if ( rv1?$var_s && rv1?$average &&
rv2?$var_s && rv2?$average )
{
local rv1_avg_sq = (rv1$average - result$average);
rv1_avg_sq = rv1_avg_sq*rv1_avg_sq;
local rv2_avg_sq = (rv2$average - result$average);
rv2_avg_sq = rv2_avg_sq*rv2_avg_sq;
result$var_s = rv1$num*(rv1$var_s/rv1$num + rv1_avg_sq) + rv2$num*(rv2$var_s/rv2$num + rv2_avg_sq);
}
else if ( rv1?$var_s )
result$var_s = rv1$var_s;
else if ( rv2?$var_s )
result$var_s = rv2$var_s;
if ( rv1?$prev_avg && rv2?$prev_avg )
result$prev_avg = ((rv1$prev_avg*rv1$num) + (rv2$prev_avg*rv2$num))/(rv1$num+rv2$num);
else if ( rv1?$prev_avg )
result$prev_avg = rv1$prev_avg;
else if ( rv2?$prev_avg )
result$prev_avg = rv2$prev_avg;
calc_variance(result);
}