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bugs - Cannot get nearest neighbors from Nearest


Bug introduced in 10 and fixed in 10.3


There still persists the failure to return 30.72 (another bug according to Daniel Lichtblau but from the developer's point of view it may be a feature).



Nearest[data,x,{n,r}] is supposed to give the n or fewer nearest neighbors to x that are within radius r of x. Example:


Nearest[{1, 2, 3, 4, 5, 6}, 3.6, {10, 1.5}] (* gives {4, 3, 5} *)
Nearest[{1, 2, 3, 4, 5, 6}, 3, {10, 2}] (* gives {3, 2, 4, 1, 5}, so it's inclusive *)

But this is not working for my data:


v = {10.38,17.77,21.25,20.38,14.34,15.7,19.98,20.83,21.82,24.04,23.24,17.89,24.8,23.95,22.61,27.54,20.13,20.68,22.15,14.36,15.71,12.44,14.26,23.04,21.38,16.4,21.53,20.25,25.27,15.05,25.11,18.7,23.98,26.47,17.88,21.59,21.72,18.42,25.2,20.82,21.58,21.35,24.81,20.28,21.81,17.6,16.84,18.66,14.63,22.3,21.6,16.34,18.24,18.7,22.02,18.75,18.57,21.59,19.31,11.79,14.88,20.98,22.15,13.86,23.84,23.94,21.01,19.04,17.33,16.49,21.31,14.64,24.52,15.79,16.52,19.65,10.94,16.15,23.97,18,20.97,15.86,24.91,26.29,15.65,18.52,21.46,24.59,21.8,15.24,24.02,22.76,14.76,18.3,19.83,23.03,17.84,19.94,12.84,19.77,24.98,13.43,20.52,19.4,19.29,15.56,18.33,18.54,19.67,21.26,16.99,20.76,19.65,20.19,15.83,21.53,15.76,16.67,22.91,20.01,10.82,17.12,20.2,10.89,16.39,17.21,24.69,18.91,16.39,25.12,13.29,19.48,21.54,13.93,21.91,22.47,16.67,15.39,17.57,13.39,11.97,18.05,17.31,15.92,14.97,14.65,16.58,18.77,15.18,17.91,20.78,20.7,15.34,13.08,15.34,17.94,20.74,19.46,12.74,12.96,20.18,15.94,18.15,22.22,22.04,19.76,9.71,18.8,24.68,16.95,12.39,19.63,11.89,14.71,15.15,14.45,18.06,20.11,22.22,13.06,21.87,26.57,20.31,14.92,22.41,15.11,18.58,17.19,17.39,15.9,23.12,21.41,18.22,26.86,23.21,16.33,22.29,21.84,22.49,20.22,19.56,19.32,26.67,23.75,18.6,16.68,17.27,20.26,22.54,12.91,22.14,18.94,18.47,25.56,23.81,16.93,18.35,17.48,21.56,32.47,13.16,13.9,17.53,20.25,17.02,13.47,15.46,15.51,23.97,22.33,19.08,27.08,33.81,27.81,15.91,21.25,26.97,21.46,27.85,39.28,15.6,15.04,18.19,23.77,23.5,19.86,17.43,14.11,25.22,14.93,23.56,18.45,19.82,17.08,19.33,17.05,28.77,17.27,23.2,33.56,27.06,23.06,22.13,19.38,22.07,31.12,18.95,21.84,16.21,20.39,16.82,13.04,20.99,15.67,24.48,17.36,14.16,19.98,17.84,15.18,26.6,14.02,18.18,18.77,15.7,18.4,20.76,13.12,19.96,18.89,19.73,19.1,16.02,17.46,13.78,13.27,12.35,18.14,18.17,23.09,18.9,19.89,23.86,18.61,18.16,24.49,15.82,14.4,12.71,13.84,19.11,15.69,13.37,10.72,18.6,16.85,14.08,18.87,18.9,17,16.18,19.66,13.32,21.51,15.21,17.3,12.88,17.93,20.71,21.88,15.51,19.35,19.86,14.78,19.02,21,14.23,21.43,17.53,24.27,16.54,16.84,14.96,21.68,15.45,14.71,18.9,14.74,16.03,14.96,17.07,19.22,17.46,25.74,14.07,19.07,18.59,16.21,15.49,18.32,18.07,21.57,18.84,18.29,16.95,21.78,26.83,18.02,17.25,21.9,23.29,13.21,15.1,17.35,16.07,16.07,20.22,28.21,15.15,18.83,12.96,14.93,22.72,17.48,13.72,23.29,14.09,16.16,15.5,23.21,12.22,16.84,19.97,22.28,17.72,17.18,18.89,17.46,14.83,17.26,21.02,10.91,18.29,16.17,14.95,18.59,14.86,21.37,20.66,17.92,17.57,16.83,21.68,22.11,29.81,21.17,21.7,21.08,12.17,21.41,19.04,13.98,16.02,19.13,19.12,21.28,14.98,21.98,16.62,17.67,22.53,17.68,19.54,21.97,16.94,19.62,19.54,15.98,19.6,15.66,17.2,25.42,15.79,18.32,16.85,24.89,28.03,17.66,19.34,20.52,21.54,25,28.23,13.98,17.15,30.72,29.29,25.25,25.13,28.2,27.15,26.27,26.99,18.36,18.22,20.13,20.74,18.1,23.33,18.18,18.49,28.14,14.93,29.97,15.62,15.73,20.53,16.62,14.59,19.51,18.03,19.24,14.06,17.64,11.28,16.41,16.85,18.82,16.17,20.2,22.44,13.23,20.56,12.83,20.54,20.21,18.17,17.31,17.52,21.24,16.74,24.49,16.32,19.83,12.87,13.14,20.04,17.12,15.7,23.95,14.69,14.7,20.52,13.66,19.07,18.61,20.58,20.26,18.22,16.7,13.9,21.6,19.83,18.68,15.68,13.1,18.75,12.27,13.17,13.44,17.56,20.02,16.33,20.67,17.62,20.86,22.55,24.44,25.49,25.44,14.44,24.99,25.42,28.06,20.7,23.23,16.35,16.58,19.34,24.21,21.48,22.44,29.43,21.94,28.92,27.61,19.59,27.88,22.68,23.93,27.15,29.37,30.62,25.09,22.39,28.25,28.08,29.33,24.54}


Nearest[v, 39.28, 6]
(* gives {39.28, 33.81, 33.56, 32.47, 31.12, 30.72}, which is fine *)

Nearest[v, 39.28, {6, 8.56}]
(* should have given the same answer because 39.28 - 30.72 = 8.56,
   but gives {39.28} instead *)

Nearest[v, 39.28, {6, 9}]
(* same as above, which is even stranger *)


I cannot explain this behavior. Any ideas?


Mathematica version: 10.2.0.0




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