numpy数据集练习

import numpy as np
l=list(range(10))
a=np.arange(10)
b=np.array([a,2*a])

print(type(l),type(a),type(b),type(l[0]),type(a[0]),a.dtype,b.dtype)


l.append("xiaodudu")
print(l)

  

a.reshape(2,5)

  

a[3:7]

  

a[:7:2]

  

b.reshape(5,4,1)

  

b.ravel()

  

b.flatten()

  

b.shape=(4,5)

  

b.transpose()

  

c=list(range(10))
d=np.arange(5)
e=np.array([c,d])
f=np.arange(0,60,5).reshape(3,4)
g=np.linspace(0,20)
h=np.random.random(10)
i=np.random.randint(1,100,[5,5])#范围和矩阵形状
j=np.random.rand(2,3)#均匀分布随机数组
k=np.random.randn(3,3)#正态分布随机数组

  

np.max(c)
np.mean(i)
np.std(k)
np.median(k)

  

  




import numpy as np # 从sklearn包自带的数据集中读出鸢尾花数据集data from sklearn.datasets import load_iris data = load_iris() # 查看data类型,包含哪些数据 print("数据类型:",type(data)) print("数据类目:",data.keys()) # 取出鸢尾花特征和鸢尾花类别数据,查看其形状及数据类型 iris_feature = data.feature_names,data.data print("鸢尾花特征:",iris_feature) print("iris_feature数据类型",type(iris_feature)) iris_target = data.target print("鸢尾花数据类别:",iris_target) print("iris_target数据类型:",type(iris_target)) # 取出所有花的花萼长度(cm)的数据 sepal_len = np.array(list(len[0] for len in data.data)) print("花萼长度:",sepal_len) # 取出所有花的花瓣长度(cm)+花瓣宽度(cm)的数据 pental_len = np.array(list(len[2] for len in data.data)) pental_len.resize(3,50) #重新分配花瓣长度内存 pental_wid = np.array(list(len[3] for len in data.data)) pental_wid.resize(3,50) #重新分配花瓣宽度内存 iris_lens = (pental_len,pental_wid) print("花瓣长宽:",iris_lens) # 取出某朵花的四个特征及其类别 print("特征:",data.data[1]) print("类别:",data.target[1]) # 将所有花的特征和类别分成三组,每组50个 #建立3个相应列表存放数据 iris_set = [] iris_ver = [] iris_vir = [] for i in range(0,150): if data.target[i] == 0: Data = data.data[i].tolist() Data.append('setosa') iris_set.append(Data) elif data.target[i] ==1: Data = data.data[i].tolist() Data.append('versicolor') iris_ver.append(Data) else: Data = data.data[i].tolist() Data.append('virginica') iris_vir.append(Data) # 生成新的数组,每个元素包含四个特征+类别 datas = (iris_set,iris_ver,iris_vir) print("新的数组:",datas)

  

data=iris['data']
X=data[:,3]
X
import numpy as np
import matplotlib.pyplot as plt
x=np.linspace(0,150,num=150)
plt.plot(x,X)
plt.show()
plt.scatter(x,X)
plt.show()

  

from sklearn.datasets import load_iris
iris=load_iris()
iris.keys() #查看data类型,包含哪些数据
Out[3]:
dict_keys(['data', 'target', 'target_names', 'DESCR', 'feature_names'])
In [34]:
data1=iris['data']
data1#"鸢尾花特征
#type(data1)#鸢尾花特征数据类型
data1.transpose()#转置形状矩阵
Out[34]:
array([[5.1, 4.9, 4.7, 4.6, 5. , 5.4, 4.6, 5. , 4.4, 4.9, 5.4, 4.8, 4.8,
        4.3, 5.8, 5.7, 5.4, 5.1, 5.7, 5.1, 5.4, 5.1, 4.6, 5.1, 4.8, 5. ,
        5. , 5.2, 5.2, 4.7, 4.8, 5.4, 5.2, 5.5, 4.9, 5. , 5.5, 4.9, 4.4,
        5.1, 5. , 4.5, 4.4, 5. , 5.1, 4.8, 5.1, 4.6, 5.3, 5. , 7. , 6.4,
        6.9, 5.5, 6.5, 5.7, 6.3, 4.9, 6.6, 5.2, 5. , 5.9, 6. , 6.1, 5.6,
        6.7, 5.6, 5.8, 6.2, 5.6, 5.9, 6.1, 6.3, 6.1, 6.4, 6.6, 6.8, 6.7,
        6. , 5.7, 5.5, 5.5, 5.8, 6. , 5.4, 6. , 6.7, 6.3, 5.6, 5.5, 5.5,
        6.1, 5.8, 5. , 5.6, 5.7, 5.7, 6.2, 5.1, 5.7, 6.3, 5.8, 7.1, 6.3,
        6.5, 7.6, 4.9, 7.3, 6.7, 7.2, 6.5, 6.4, 6.8, 5.7, 5.8, 6.4, 6.5,
        7.7, 7.7, 6. , 6.9, 5.6, 7.7, 6.3, 6.7, 7.2, 6.2, 6.1, 6.4, 7.2,
        7.4, 7.9, 6.4, 6.3, 6.1, 7.7, 6.3, 6.4, 6. , 6.9, 6.7, 6.9, 5.8,
        6.8, 6.7, 6.7, 6.3, 6.5, 6.2, 5.9],
       [3.5, 3. , 3.2, 3.1, 3.6, 3.9, 3.4, 3.4, 2.9, 3.1, 3.7, 3.4, 3. ,
        3. , 4. , 4.4, 3.9, 3.5, 3.8, 3.8, 3.4, 3.7, 3.6, 3.3, 3.4, 3. ,
        3.4, 3.5, 3.4, 3.2, 3.1, 3.4, 4.1, 4.2, 3.1, 3.2, 3.5, 3.1, 3. ,
        3.4, 3.5, 2.3, 3.2, 3.5, 3.8, 3. , 3.8, 3.2, 3.7, 3.3, 3.2, 3.2,
        3.1, 2.3, 2.8, 2.8, 3.3, 2.4, 2.9, 2.7, 2. , 3. , 2.2, 2.9, 2.9,
        3.1, 3. , 2.7, 2.2, 2.5, 3.2, 2.8, 2.5, 2.8, 2.9, 3. , 2.8, 3. ,
        2.9, 2.6, 2.4, 2.4, 2.7, 2.7, 3. , 3.4, 3.1, 2.3, 3. , 2.5, 2.6,
        3. , 2.6, 2.3, 2.7, 3. , 2.9, 2.9, 2.5, 2.8, 3.3, 2.7, 3. , 2.9,
        3. , 3. , 2.5, 2.9, 2.5, 3.6, 3.2, 2.7, 3. , 2.5, 2.8, 3.2, 3. ,
        3.8, 2.6, 2.2, 3.2, 2.8, 2.8, 2.7, 3.3, 3.2, 2.8, 3. , 2.8, 3. ,
        2.8, 3.8, 2.8, 2.8, 2.6, 3. , 3.4, 3.1, 3. , 3.1, 3.1, 3.1, 2.7,
        3.2, 3.3, 3. , 2.5, 3. , 3.4, 3. ],
       [1.4, 1.4, 1.3, 1.5, 1.4, 1.7, 1.4, 1.5, 1.4, 1.5, 1.5, 1.6, 1.4,
        1.1, 1.2, 1.5, 1.3, 1.4, 1.7, 1.5, 1.7, 1.5, 1. , 1.7, 1.9, 1.6,
        1.6, 1.5, 1.4, 1.6, 1.6, 1.5, 1.5, 1.4, 1.5, 1.2, 1.3, 1.5, 1.3,
        1.5, 1.3, 1.3, 1.3, 1.6, 1.9, 1.4, 1.6, 1.4, 1.5, 1.4, 4.7, 4.5,
        4.9, 4. , 4.6, 4.5, 4.7, 3.3, 4.6, 3.9, 3.5, 4.2, 4. , 4.7, 3.6,
        4.4, 4.5, 4.1, 4.5, 3.9, 4.8, 4. , 4.9, 4.7, 4.3, 4.4, 4.8, 5. ,
        4.5, 3.5, 3.8, 3.7, 3.9, 5.1, 4.5, 4.5, 4.7, 4.4, 4.1, 4. , 4.4,
        4.6, 4. , 3.3, 4.2, 4.2, 4.2, 4.3, 3. , 4.1, 6. , 5.1, 5.9, 5.6,
        5.8, 6.6, 4.5, 6.3, 5.8, 6.1, 5.1, 5.3, 5.5, 5. , 5.1, 5.3, 5.5,
        6.7, 6.9, 5. , 5.7, 4.9, 6.7, 4.9, 5.7, 6. , 4.8, 4.9, 5.6, 5.8,
        6.1, 6.4, 5.6, 5.1, 5.6, 6.1, 5.6, 5.5, 4.8, 5.4, 5.6, 5.1, 5.1,
        5.9, 5.7, 5.2, 5. , 5.2, 5.4, 5.1],
       [0.2, 0.2, 0.2, 0.2, 0.2, 0.4, 0.3, 0.2, 0.2, 0.1, 0.2, 0.2, 0.1,
        0.1, 0.2, 0.4, 0.4, 0.3, 0.3, 0.3, 0.2, 0.4, 0.2, 0.5, 0.2, 0.2,
        0.4, 0.2, 0.2, 0.2, 0.2, 0.4, 0.1, 0.2, 0.1, 0.2, 0.2, 0.1, 0.2,
        0.2, 0.3, 0.3, 0.2, 0.6, 0.4, 0.3, 0.2, 0.2, 0.2, 0.2, 1.4, 1.5,
        1.5, 1.3, 1.5, 1.3, 1.6, 1. , 1.3, 1.4, 1. , 1.5, 1. , 1.4, 1.3,
        1.4, 1.5, 1. , 1.5, 1.1, 1.8, 1.3, 1.5, 1.2, 1.3, 1.4, 1.4, 1.7,
        1.5, 1. , 1.1, 1. , 1.2, 1.6, 1.5, 1.6, 1.5, 1.3, 1.3, 1.3, 1.2,
        1.4, 1.2, 1. , 1.3, 1.2, 1.3, 1.3, 1.1, 1.3, 2.5, 1.9, 2.1, 1.8,
        2.2, 2.1, 1.7, 1.8, 1.8, 2.5, 2. , 1.9, 2.1, 2. , 2.4, 2.3, 1.8,
        2.2, 2.3, 1.5, 2.3, 2. , 2. , 1.8, 2.1, 1.8, 1.8, 1.8, 2.1, 1.6,
        1.9, 2. , 2.2, 1.5, 1.4, 2.3, 2.4, 1.8, 1.8, 2.1, 2.4, 2.3, 1.9,
        2.3, 2.5, 2.3, 1.9, 2. , 2.3, 1.8]])
In [17]:
data2=iris['target']
data2
Out[17]:
array([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
       0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
       0, 0, 0, 0, 0, 0, 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, 1, 1, 1,
       1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
       2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
       2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2])
In [28]:
import numpy as np
data=iris['data']
a=np.array(data[:,2])
a
Out[28]:
array([1.4, 1.4, 1.3, 1.5, 1.4, 1.7, 1.4, 1.5, 1.4, 1.5, 1.5, 1.6, 1.4,
       1.1, 1.2, 1.5, 1.3, 1.4, 1.7, 1.5, 1.7, 1.5, 1. , 1.7, 1.9, 1.6,
       1.6, 1.5, 1.4, 1.6, 1.6, 1.5, 1.5, 1.4, 1.5, 1.2, 1.3, 1.5, 1.3,
       1.5, 1.3, 1.3, 1.3, 1.6, 1.9, 1.4, 1.6, 1.4, 1.5, 1.4, 4.7, 4.5,
       4.9, 4. , 4.6, 4.5, 4.7, 3.3, 4.6, 3.9, 3.5, 4.2, 4. , 4.7, 3.6,
       4.4, 4.5, 4.1, 4.5, 3.9, 4.8, 4. , 4.9, 4.7, 4.3, 4.4, 4.8, 5. ,
       4.5, 3.5, 3.8, 3.7, 3.9, 5.1, 4.5, 4.5, 4.7, 4.4, 4.1, 4. , 4.4,
       4.6, 4. , 3.3, 4.2, 4.2, 4.2, 4.3, 3. , 4.1, 6. , 5.1, 5.9, 5.6,
       5.8, 6.6, 4.5, 6.3, 5.8, 6.1, 5.1, 5.3, 5.5, 5. , 5.1, 5.3, 5.5,
       6.7, 6.9, 5. , 5.7, 4.9, 6.7, 4.9, 5.7, 6. , 4.8, 4.9, 5.6, 5.8,
       6.1, 6.4, 5.6, 5.1, 5.6, 6.1, 5.6, 5.5, 4.8, 5.4, 5.6, 5.1, 5.1,
       5.9, 5.7, 5.2, 5. , 5.2, 5.4, 5.1])
In [37]:
data[1]#谋朵花的的四种特征
Out[37]:
array([4.9, 3. , 1.4, 0.2])
In [38]:
data2[1]#某朵花的类别
Out[38]:
0

  

原文地址:https://www.cnblogs.com/cc013/p/9787881.html