bream_length = [25.4, 26.3, 26.5, 29.0, 29.0, 29.7, 29.7, 30.0, 30.0, 30.7, 31.0, 31.0, 31.5, 32.0, 32.0, 32.0, 33.0, 33.0, 33.5, 33.5, 34.0, 34.0, 34.5, 35.0, 35.0, 35.0, 35.0, 36.0, 36.0, 37.0, 38.5, 38.5, 39.5, 41.0, 41.0]
bream_weight = [242.0, 290.0, 340.0, 363.0, 430.0, 450.0, 500.0, 390.0, 450.0, 500.0, 475.0, 500.0, 500.0, 340.0, 600.0, 600.0, 700.0, 700.0, 610.0, 650.0, 575.0, 685.0, 620.0, 680.0, 700.0, 725.0, 720.0, 714.0, 850.0, 1000.0, 920.0, 955.0, 925.0, 975.0, 950.0]
import matplotlib.pyplot as plt
plt.scatter(bream_length, bream_weight)
plt.xlabel('length')
plt.ylabel('weight')
plt.show()
smelt_length = [9.8, 10.5, 10.6, 11.0, 11.2, 11.3, 11.8, 11.8, 12.0, 12.2, 12.4, 13.0, 14.3, 15.0]
smelt_weight = [6.7, 7.5, 7.0, 9.7, 9.8, 8.7, 10.0, 9.9, 9.8, 12.2, 13.4, 12.2, 19.7, 19.9]
plt.scatter(bream_length, bream_weight)
plt.scatter(smelt_length, smelt_weight)
plt.xlabel('length')
plt.ylabel('weight')
plt.show()
length = bream_length+smelt_length
weight = bream_weight+smelt_weight
fish_data = [[l, w] for l, w in zip(length, weight)]
print(fish_data)
[[25.4, 242.0], [26.3, 290.0], [26.5, 340.0], [29.0, 363.0], [29.0, 430.0], [29.7, 450.0], [29.7, 500.0], [30.0, 390.0], [30.0, 450.0], [30.7, 500.0], [31.0, 475.0], [31.0, 500.0], [31.5, 500.0], [32.0, 340.0], [32.0, 600.0], [32.0, 600.0], [33.0, 700.0], [33.0, 700.0], [33.5, 610.0], [33.5, 650.0], [34.0, 575.0], [34.0, 685.0], [34.5, 620.0], [35.0, 680.0], [35.0, 700.0], [35.0, 725.0], [35.0, 720.0], [36.0, 714.0], [36.0, 850.0], [37.0, 1000.0], [38.5, 920.0], [38.5, 955.0], [39.5, 925.0], [41.0, 975.0], [41.0, 950.0], [9.8, 6.7], [10.5, 7.5], [10.6, 7.0], [11.0, 9.7], [11.2, 9.8], [11.3, 8.7], [11.8, 10.0], [11.8, 9.9], [12.0, 9.8], [12.2, 12.2], [12.4, 13.4], [13.0, 12.2], [14.3, 19.7], [15.0, 19.9]]
fish_target = [1]*35 + [0]*14
print(fish_target)
[1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
from sklearn.neighbors import KNeighborsClassifier
kn = KNeighborsClassifier()
kn.fit(fish_data, fish_target)
KNeighborsClassifier()In a Jupyter environment, please rerun this cell to show the HTML representation or trust the notebook.
KNeighborsClassifier()
kn.score(fish_data, fish_target)
1.0
plt.scatter(bream_length, bream_weight)
plt.scatter(smelt_length, smelt_weight)
plt.scatter(30, 600, marker='^')
plt.xlabel('length')
plt.ylabel('weight')
plt.show()
kn.predict([[30, 600]])
array([1])
print(kn._fit_X)
[[ 25.4 242. ] [ 26.3 290. ] [ 26.5 340. ] [ 29. 363. ] [ 29. 430. ] [ 29.7 450. ] [ 29.7 500. ] [ 30. 390. ] [ 30. 450. ] [ 30.7 500. ] [ 31. 475. ] [ 31. 500. ] [ 31.5 500. ] [ 32. 340. ] [ 32. 600. ] [ 32. 600. ] [ 33. 700. ] [ 33. 700. ] [ 33.5 610. ] [ 33.5 650. ] [ 34. 575. ] [ 34. 685. ] [ 34.5 620. ] [ 35. 680. ] [ 35. 700. ] [ 35. 725. ] [ 35. 720. ] [ 36. 714. ] [ 36. 850. ] [ 37. 1000. ] [ 38.5 920. ] [ 38.5 955. ] [ 39.5 925. ] [ 41. 975. ] [ 41. 950. ] [ 9.8 6.7] [ 10.5 7.5] [ 10.6 7. ] [ 11. 9.7] [ 11.2 9.8] [ 11.3 8.7] [ 11.8 10. ] [ 11.8 9.9] [ 12. 9.8] [ 12.2 12.2] [ 12.4 13.4] [ 13. 12.2] [ 14.3 19.7] [ 15. 19.9]]
print(kn._y)
[1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0]
kn49 = KNeighborsClassifier(n_neighbors=49)
kn49.fit(fish_data, fish_target)
kn49.score(fish_data, fish_target)
0.7142857142857143
print(35/49)
0.7142857142857143
kn = KNeighborsClassifier()
kn.fit(fish_data, fish_target)
for n in range(5, 50):
# 최근접 이웃 개수 설정
kn.n_neighbors = n
# 점수 계산
score = kn.score(fish_data, fish_target)
# 100% 정확도에 미치지 못하는 이웃 개수 출력
if score < 1:
print(n, score)
break
18 0.9795918367346939