stats
Usage:
stats [-[no]parallel] [-qapprox|-qexact] [<item> ...]
Calculates statistics on the data in the table. This filter turns the table sideways, so that each row of the output corresponds to a column of the input. The columns of the output table contain statistical items such as mean, standard deviation etc corresponding to each column of the input table.
By default the output table contains columns for the following items:
Name
: Column nameMean
: AverageStDev
: Population Standard deviationMinimum
: Numeric minimumMaximum
: Numeric maximumNGood
: Number of non-blank cellsHowever, the output may be customised by supplying one or more
<item>
headings. These may be selected
from the above as well as the following:
NBad
: Number of blank cellsVariance
: Population VarianceSampStDev
: Sample Standard DeviationSampVariance
: Sample VarianceMedAbsDev
: Median Absolute DeviationScMedAbsDev
: Median Absolute Deviation * 1.4826Skew
: Gamma 1 skewness measureKurtosis
: Gamma 2 peakedness measureSum
: Sum of valuesMinPos
: Row index of numeric minimumMaxPos
: Row index of numeric maximumCardinality
: Number of distinct values in column; values >100 ignoredMedian
: Middle value in sequenceQuartile1
: First quartileQuartile2
: Second quartileQuartile3
: Third quartileQ.25
: First quartileQ.625
: Fifth octileAny parameters of the input table are propagated to the output one.
The -qapprox
or -qexact
flag controls how quantiles are calculated.
With -qexact
they are calculated exactly,
but this requires memory usage scaling with the number of rows.
If the -qapprox
flag is supplied,
an method is used which is typically slower and produces only
approximate values, but which will work in fixed memory
and so can be used for arbitrarily large tables.
By default, exact calculation is used.
These flags are ignored if neither quantiles nor the MAD
are being calculated
The -noparallel
flag may be supplied to inhibit
multi-threaded statistics accumulation.
Calculation is done in parallel by default if multi-threaded
hardware is available, and it's usually faster.