TDigest of 1M samples uniform in [0..1]:
    
approximating 1000000 samples using 761 centroids
min = 2.9288356295786855e-7
Q1  = 0.2510225687517002
Q2  = 0.5008974258361709
Q3  = 0.7502745044449638
max = 0.9999991808742237