Chris mentioned he wanted to be able to measure a variable "for one
second" and use igt_stats to store them. That's one case where we don't
know the number of data points upfront.
We should really support that, so here it is.
v2: Just free ->sorted when a new capacity is needed.
ensure_sorted_values() will then reallocate the array to the new
capacity on demand (Chris)
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
This changes how we compute the variance. We want an unbiased variance
when reasoning about a sample.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Because the structure started small, I initialized every member
directly, but that means that the new fields added weren't properly
initialized (sigh!). Zero the whole thing first then.
Also, the punishment for introducing a bug should be to write the
corresponding unit test. It's not a perfect one, but I'll take it.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
The master plan would be to get a bit more stats in it, at least the
standard deviation and confidence interval. Just need the average for
now.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>