Temporal count

tcount(tnpoint): {tint_instset,tint_seqset}

WITH Temp(temp) AS (
SELECT tnpoint '[NPoint(1, 0.1)@2012-01-01, NPoint(1, 0.3)@2012-01-03)' UNION
SELECT tnpoint '[NPoint(1, 0.2)@2012-01-02, NPoint(1, 0.4)@2012-01-04)' UNION
SELECT tnpoint '[NPoint(1, 0.3)@2012-01-03, NPoint(1, 0.5)@2012-01-05)' )
SELECT tcount(Temp)
FROM Temp
-- {[1@2012-01-01, 2@2012-01-02, 1@2012-01-04, 1@2012-01-05)}

Window count

wcount(tnpoint): {tint_instset,tint_seqset}

WITH Temp(temp) AS (
SELECT tnpoint '[NPoint(1, 0.1)@2012-01-01, NPoint(1, 0.3)@2012-01-03)' UNION
SELECT tnpoint '[NPoint(1, 0.2)@2012-01-02, NPoint(1, 0.4)@2012-01-04)' UNION
SELECT tnpoint '[NPoint(1, 0.3)@2012-01-03, NPoint(1, 0.5)@2012-01-05)' )
SELECT wcount(Temp, '1 day')
FROM Temp
-- {[1@2012-01-01, 2@2012-01-02, 3@2012-01-03, 2@2012-01-04, 1@2012-01-05,
  1@2012-01-06)}

Temporal centroid

tcentroid(tnpoint): tgeompoint

WITH Temp(temp) AS (
SELECT tnpoint '[NPoint(1, 0.1)@2012-01-01, NPoint(1, 0.3)@2012-01-03)' UNION
SELECT tnpoint '[NPoint(1, 0.2)@2012-01-01, NPoint(1, 0.4)@2012-01-03)' UNION
SELECT tnpoint '[NPoint(1, 0.3)@2012-01-01, NPoint(1, 0.5)@2012-01-03)' )
SELECT astext(tcentroid(Temp))
FROM Temp
-- {[POINT(72.451531682218 76.5231414472853)@2012-01-01,
  POINT(55.7001249027598 72.9552602410653)@2012-01-03)}