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NAME
	median - Calculate the median values for a set of groups

SYNOPSIS
	median

DESCRIPTION
	median takes the first blank space-separated column values
	and the remainder as keys. It will then print the median for
	each key. Lines with the same key form a group.

	median outputs the median value for each key, no order of
	the output lines are prescribed. No order is prescribed for
	the input lines.

	Lines without a blank space are parsed as having the empty
	string as the key, for lines with a blank space, the first
	blank space is parsed as part of the key.

	For groups with an even number of elements, if the mean of
	the middle two values are used as the median if all values
	in the group are numerical, otherwise the lower value is
	used as the median.

EXAMPLES
	$ cat <<EOF | median
	-10
	2
	4
	3
	50
	EOF
	3

	$ cat <<EOF | median
	+003  c
	.001  a
	-002  b
	+001  c
	-001  b
	+002  c
	EOF
	.001  a
	-001.5  b
	+002  c

RATIONALE
	Combining sort(1), sed(1), wc(1), expr(1) to do this is
	too much work to do on a regular basis.

SEE ALSO
	sort(1), expr(1), sets(1)