Rand index over 1

[seyseykun]

When performing ruptures.metric.randindex(bkps1, bkps2) with the two lists below, I obtain a value of 1.002088251282002, while the Rand index is supposed to be between 0 and 1.

bkps1 = [5338, 6766, 7154, 7173, 12244, 14707, 17672, 19448, 19460, 20717, 20732, 21327, 22265, 22591, 24695, 25372, 25936, 26073, 26316, 26326, 26901, 26969, 29887, 29901, 30364, 30433, 32905, 36333, 39037, 39054, 40446, 42076, 43532, 44262, 47820, 48304, 50871, 51038, 53561, 62202, 65810, 67386, 68141, 68235, 68626, 70421, 70435, 70937, 79021, 81554, 84436, 87278, 87521, 88402, 94163, 97984, 98228, 98715, 99506, 100627, 100643, 101298, 101326, 102490, 102665, 102766, 102839, 104923, 110593, 111396, 111426, 111665, 113245, 121000, 126768, 127192, 127714, 129647, 129657, 131620, 146273, 151044, 151706, 152275, 152346, 152364, 152488, 154343, 154901, 154969, 155749, 155761, 155947, 156692, 156703, 160531, 164525, 172328, 174394, 174422, 175323, 175412, 175761, 176158, 176185, 178372, 178989, 180630, 184193, 184525, 190080, 190542, 192530, 195278, 195431, 196043, 196417, 196965, 197430, 198130, 198151, 201606, 205640, 205671, 206618, 206668, 210409, 210420, 212581, 219433, 223396, 223508, 224304, 226933, 227370, 227585, 230335, 233442, 236232, 236529, 236545, 236756, 236769, 237162, 240479, 240509, 240716, 240974, 241945, 242283, 242627, 242645, 242992, 243520, 243897, 243909, 244634, 244650, 244829, 246488, 246910, 246922, 246980, 247010, 247216, 247231, 247462, 248486, 248707, 248991, 249774, 249799, 254087, 254104, 256966, 257630, 257790, 260062, 261281, 263240, 263885, 264176, 277763, 281755, 282414, 282757, 282768, 283029, 283044, 283789, 284876, 284886, 289298, 291351, 296145, 297357, 306611, 308622, 308682, 312052, 312070, 314924, 314934, 315949, 316148, 316425, 316588, 316599, 316644, 316723, 316856, 316868, 317817, 317837, 318546, 319582, 319593, 320127, 320506, 320516, 321711, 323253, 323284, 323913, 324503, 324521, 324791, 324868, 324934, 324958, 324973, 325046, 325137, 325150, 325296, 325324, 325350, 325362, 328201, 329050, 329084, 329109, 331578, 333404, 333418, 335705, 347448, 349187, 349216, 350706, 350782, 350812, 350877, 350907, 351196, 351250, 351619, 351635, 353745, 353961, 353991, 356918, 361955, 380666, 380676, 382511, 383359, 383790, 384469, 386566, 386650, 394860, 427765, 439048, 440208, 442167, 460670, 493575, 498012, 500009, 525460, 526480, 530932, 532612, 532627, 533685, 533798, 533819, 534252, 534319, 534616, 534702, 534868, 534915, 534925, 535162, 535263, 537715, 539793, 539812, 541988, 546949, 559385, 572718, 592290, 595682, 602247, 602321, 614898, 617345, 617510, 621881, 625195, 646182, 647476, 647632, 648348, 648431, 650988, 658100, 661055, 661068, 667033, 670513, 691005, 720273, 723910, 737485, 746877, 747928, 749142, 749152, 756815, 785477, 787512, 789720, 791593, 799643, 802446, 803018, 803513, 803529, 804230, 807149, 807455, 808333, 808435, 809044, 809109, 809334, 809670, 809936, 812389, 812399, 813002, 816383, 821071, 822625, 823914, 825758, 825989, 828851, 831106, 831885, 832146, 832196, 832435, 833595, 834455, 834808, 835005, 835946, 837382, 837758, 840227, 842375, 842462, 842627, 842787, 842823, 842903, 843050, 843085, 843107, 843140, 846445, 855530, 856760, 861607, 862783, 866791, 867265, 867332, 867481, 867731, 867747, 867918, 868106, 868120, 869250, 869285, 869981, 870014, 870095, 870356, 870822, 871329, 871665, 872127, 872185, 872256, 872280, 872679, 872715, 872805, 874551, 874623, 874707, 874759, 875387, 875441, 878235, 878981, 888296, 888435, 888935, 888954, 889104, 889120, 892206, 892687, 899524, 908064, 908975, 908993, 909113, 909728, 909799, 909932, 910206, 910516, 911186, 911301, 913145, 915612, 921340, 923783, 927497, 928961, 933141, 933890, 935810, 935820, 938235, 938591, 938700, 938785, 938814, 939304, 941886, 941926, 942355, 943055, 943257, 943744, 944757, 945713, 946890, 947624, 948040, 948656, 949218, 950250, 951060, 951524, 951615, 951825, 952243, 953519, 954197, 954227, 954245, 955535, 957883, 958979, 958998, 959084, 959364, 960427, 960520, 964835, 975733, 978095, 981279, 981454, 982396, 984486, 984539, 984857, 985679, 985699, 985977, 985988, 986122, 987150, 989009, 989388, 989665, 990293, 990698, 990736, 991224, 991513, 991668, 991772, 991796, 992179, 992192, 992723, 992814, 993679, 993731, 993957, 994145, 995303, 995319, 995796, 995949, 997255, 997318, 998299, 999520, 1000174, 1008183, 1008214, 1010030, 1010556, 1010813, 1011066, 1011513, 1012490, 1015402, 1016157, 1016761, 1017215, 1017399, 1017527, 1018674, 1019057, 1019509, 1019526, 1020055, 1020447, 1020478, 1023739, 1031564, 1031766, 1032197, 1032637, 1033715, 1033943, 1034111, 1034345, 1034375, 1035038, 1035638, 1036425, 1037092, 1037121, 1037998, 1038054, 1039657, 1039880, 1040418, 1040726, 1041203, 1041230, 1041614, 1041631, 1042014, 1042348, 1043145, 1043636, 1043659, 1044314, 1044327, 1044615, 1045966, 1046216, 1046237, 1046922, 1047309, 1047398, 1047461, 1048269, 1048438, 1050564, 1052960, 1053640, 1055328, 1055724, 1056137, 1056154, 1059362, 1059552, 1059577, 1059771, 1061426, 1062710, 1063849, 1063916, 1065455, 1066970, 1067125, 1067218, 1067303, 1068027, 1069739, 1070393, 1070442, 1070587, 1071645, 1072258, 1072270, 1072393, 1072498, 1072777, 1073345, 1073358, 1073621, 1073879, 1076775, 1077234, 1077259, 1077461, 1077494, 1081427, 1081921, 1083157, 1083176, 1084681, 1085865, 1086837, 1088332, 1088348, 1090436, 1091042, 1091377, 1098861, 1100008, 1100051, 1101387, 1101406, 1101731, 1101810, 1101856, 1101883, 1102396, 1102420, 1103634, 1103662, 1105092, 1108992, 1114505, 1118066, 1118079, 1118770, 1127423, 1131203, 1140349, 1142714, 1142725, 1143407, 1150773, 1151675, 1152082, 1152407, 1152462, 1153185, 1153195, 1154100, 1154155, 1154280, 1154363, 1154375, 1154856, 1154910, 1155173, 1155337, 1156353, 1157361, 1157515, 1157969, 1158121, 1158295, 1158350, 1158412, 1158446, 1158501, 1158527, 1158870, 1159555, 1159586, 1160299, 1160363, 1160462, 1160475, 1160642, 1160783, 1160884, 1160956, 1161217, 1161231, 1161631, 1161686, 1161799, 1161822, 1162103, 1162146, 1163916, 1163962, 1164449, 1164488, 1166399, 1168108, 1169205, 1169561, 1173838, 1184580, 1194988, 1205328, 1209703, 1212616, 1217485, 1225055, 1225071, 1236091, 1244532, 1250390, 1258592, 1264860, 1265052, 1267668, 1267678, 1271053, 1275278, 1278754, 1283295]

bkps2 = [6238, 7179, 17679, 25307, 26969, 32905, 38071, 43532, 44262, 50868, 51038, 53561, 62202, 65810, 67386, 70943, 81556, 84436, 88369, 94163, 98715, 101282, 102841, 104923, 110593, 111396, 111665, 126784, 128464, 131620, 147038, 152283, 152410, 154901, 154969, 157020, 160531, 164525, 172870, 175201, 178989, 192932, 196041, 196400, 197430, 201606, 211153, 219433, 227845, 230335, 236506, 244830, 246880, 249037, 256966, 263240, 264176, 277763, 281755, 282241, 284894, 289297, 296145, 311961, 316587, 316723, 321711, 324500, 325368, 328201, 329050, 335705, 348044, 351196, 351250, 351696, 353745, 353991, 361955, 382165, 386728, 394860, 427765, 439200, 442167, 460670, 493575, 526480, 532555, 535271, 537715, 546710, 559385, 592290, 614829, 621881, 625195, 646193, 650982, 658100, 661269, 667047, 691005, 723910, 737485, 747928, 756815, 785476, 789720, 791593, 800253, 804230, 807456, 808436, 809334, 809670, 809936, 822625, 825688, 825989, 829320, 831636, 833598, 834455, 834869, 837925, 842375, 842903, 843050, 843140, 846445, 855530, 866791, 872112, 872281, 872667, 872805, 874551, 874824, 879017, 888435, 892724, 899524, 908064, 911301, 915607, 921340, 932977, 938235, 939304, 942337, 949280, 951322, 951895, 953519, 954245, 958934, 959364, 961181, 978093, 984858, 986122, 987150, 990278, 995794, 1010552, 1012490, 1016761, 1017527, 1020055, 1023739, 1033718, 1034415, 1039657, 1039878, 1042014, 1042348, 1043145, 1044619, 1046922, 1047309, 1048269, 1048438, 1050564, 1052960, 1053640, 1055328, 1055724, 1061283, 1066904, 1068027, 1069667, 1072393, 1072770, 1076774, 1077504, 1081921, 1084681, 1085865, 1090396, 1100008, 1100051, 1101728, 1105031, 1108992, 1118770, 1127423, 1131203, 1140349, 1142714, 1142725, 1151675, 1154096, 1154915, 1157949, 1158535, 1158870, 1160956, 1162651, 1173827, 1184580, 1206073, 1217485, 1236109, 1250390, 1260591, 1270501, 1283295]

[Lucas-Prates]

Greetings!

I failed to reproduce your result. Installing the latest version (1.1.8) of ruptures, the output of the randindex method for the provided lists was $0.9968722559866201$ . I also tested it on sklearn using sklearn.metrics.randindex method. Using the same input (it has to be adapted since they handle clustering instead of change-points directly), and the output was again $0.9968722559866201$ , matching exactly ruptures output.

Could you check your output again?