i have length 520 of array and metrics.roc_curve shows only a few fpr,tpr,threshold
these are some values of my score array
[... 4.6719894 5.3444934 2.575739 3.5660675 3.4357991 4.195427
4.120169 5.021058 5.308503 5.3124313 4.8253884 4.7469654
5.0011086 5.170149 4.5555115 4.4109273 4.6183085 4.356304
4.413242 4.1186514 5.0573816 4.646429 5.063631 4.363433
5.431669 6.1605806 6.1510544 4.8733225 6.0209446 6.5198536
5.1457767 1.3887328 1.3165888 1.143339 1.717379 1.6670974
1.1816382 1.2497046 1.035109 1.4904765 1.195155 1.2590547
1.0998954 1.6484532 1.5722921 1.2841778 1.1058662 1.3368237
1.3262213 1.215088 1.4224783 1.046008 1.262415 1.2319984
1.2202312 1.1610713 1.2327379 1.1951761 1.8699458 0.98760885
1.6670336 1.5051543 1.2339936 1.5215651 1.534271 1.1805111
1.1587876 1.0894692 1.1936147 1.3278677 1.2409594 1.0499009... ]
And i got only these results
fpr [0. 0. 0. 0.00204499 0.00204499 1. ]
tpr [0. 0.03225806 0.96774194 0.96774194 1. 1. ]
threshold [7.5198536 6.5198536 3.4357991 2.5991373 2.575739 0.8769072]
what is the reason of this ?