result = 0
factorial = 1
for i in range(1, 21):
factorial *= i
result += factorial
print(result)
2561327494111820313
s = [9, 7, 8, 3, 2, 1, 55, 6]
# 计算元素个数、最大值和最小值
count = len(s)
max_num = max(s)
min_num = min(s)
# 添加一个元素10
s.append(10)
# 删除一个元素55
s.remove(55)
# 输出结果
print("列表s中元素的个数为:", count)
print("列表s中的最大数为:", max_num)
print("列表s中的最小数为:", min_num)
print("添加元素后的列表s为:", s)
列表s中元素的个数为: 8 列表s中的最大数为: 55 列表s中的最小数为: 1 添加元素后的列表s为: [9, 7, 8, 3, 2, 1, 6, 10]
TTTTTx
TTTTxx
TTTxxx
TTxxxx
Txxxxx
n = 5
for i in range(n):
print('T'*(n-i-1) + 'x'*(i+1))
TTTTx TTTxx TTxxx Txxxx xxxxx
# 定义加法函数
def add(x, y):
return x + y
# 定义减法函数
def subtract(x, y):
return x - y
# 定义乘法函数
def multiply(x, y):
return x * y
# 定义除法函数
def divide(x, y):
return x / y
# 打印菜单提示信息
print("请选择要进行的计算:")
print("1. 加法")
print("2. 减法")
print("3. 乘法")
print("4. 除法")
# 获取用户选择
choice = input("请输入计算的序号(1/2/3/4):")
# 获取用户输入的数字
num1 = float(input("请输入第一个数字:"))
num2 = float(input("请输入第二个数字:"))
# 根据用户选择调用相应的函数进行计算
if choice == '1':
result = add(num1, num2)
elif choice == '2':
result = subtract(num1, num2)
elif choice == '3':
result = multiply(num1, num2)
elif choice == '4':
result = divide(num1, num2)
else:
print("输入的计算序号不正确!")
# 输出计算结果
print("计算结果为:", result)
请选择要进行的计算: 1. 加法 2. 减法 3. 乘法 4. 除法 请输入计算的序号(1/2/3/4):3 请输入第一个数字:782 请输入第二个数字:712 计算结果为: 556784.0
class Student:
def __init__(self, name, age, course):
self.name = name
self.age = age
self.course = course
def get_name(self):
return self.name
def get_age(self):
return self.age
def get_course(self):
return max(self.course)
# 创建一个学生对象
st = Student('zhangming', 20, [69, 88, 100])
# 打印学生的姓名、年龄和最高分数
print('姓名:', st.get_name())
print('年龄:', st.get_age())
print('最高分数:', st.get_course())
姓名: zhangming 年龄: 20 最高分数: 100
X | Y | X | Y |
---|---|---|---|
-3.00 | 4 | 0.15 | 255 |
-2.50 | 12 | 0.75 | 170 |
-1.75 | 50 | 1.25 | 100 |
-1.15 | 120 | 1.85 | 20 |
-0.50 | 205 | 2.45 | 14 |
import matplotlib.pyplot as plt
import numpy as np
# 定义数据
x1 = [-3.00, -2.50, -1.75, -1.15, -0.50]
y1 = [4, 12, 50, 120, 205]
x2 = [0.15, 0.75, 1.25, 1.85, 2.45]
y2 = [255, 170, 100, 20, 14]
# 创建画布和子图对象
fig, ax = plt.subplots()
# 创建柱状图
width = 0.35
rects1 = ax.bar(x1, y1, width, label='Values 1')
rects2 = ax.bar(x2, y2, width, label='Values 2')
# 添加轴标签、标题和图例
ax.set_xlabel('X Value')
ax.set_ylabel('Y Value')
ax.set_title('Comparison of Values in Different Categories')
ax.set_xticks(x1 + x2)
ax.legend()
# 显示图形
plt.show()
注:训练集:测试集=8:2,随机种子采用你学号后两位,例如你学号后两位=01,则random_state=1,如果最后两位=34,则random_state=34。最终结果打印出各个回归的w和b系数即可。
序号 | X1 | X2 | X3 | X4 | Y |
---|---|---|---|---|---|
1 | 7 | 26 | 6 | 60 | 78.5 |
2 | 1 | 29 | 15 | 52 | 74.3 |
3 | 11 | 56 | 8 | 20 | 104.3 |
4 | 11 | 31 | 8 | 47 | 87.6 |
5 | 7 | 52 | 6 | 33 | 95.9 |
6 | 11 | 55 | 9 | 22 | 109.2 |
7 | 3 | 71 | 17 | 6 | 102.7 |
8 | 1 | 31 | 22 | 44 | 72.5 |
9 | 2 | 54 | 18 | 22 | 93.1 |
10 | 21 | 47 | 4 | 26 | 115.9 |
11 | 1 | 40 | 23 | 34 | 83.8 |
12 | 11 | 66 | 9 | 12 | 113.3 |
13 | 10 | 68 | 8 | 12 | 109.4 |
import numpy as np
from sklearn.model_selection import train_test_split
from sklearn.linear_model import LinearRegression, Ridge, Lasso
# 手动输入数据
X = np.array([[7,26,6,60],
[1,29,15,52],
[11,56,8,20],
[11,31,8,47],
[7,52,6,33],
[11,55,9,22],
[3,71,17,6],
[1,31,22,44],
[2,54,18,22],
[21,47,4,26],
[1,40,23,34],
[11,66,9,12],
[10,68,8,12]])
y = np.array([78.5, 74.3, 104.3, 87.6, 95.9, 109.2, 102.7, 72.5, 93.1, 115.9, 83.8, 113.3, 109.4])
# 划分训练集和测试集
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2, random_state=33)
# 线性回归
lr = LinearRegression()
lr.fit(X_train, y_train)
print('线性回归: w =', lr.coef_, ', b =', lr.intercept_)
# 岭回归
ridge = Ridge(alpha=1)
ridge.fit(X_train, y_train)
print('岭回归: w =', ridge.coef_, ', b =', ridge.intercept_)
# Lasso回归
lasso = Lasso(alpha=0.1)
lasso.fit(X_train, y_train)
print('Lasso回归: w =', lasso.coef_, ', b =', lasso.intercept_)
线性回归: w = [1.8345409 0.94625926 0.44872786 0.21458594] , b = 25.07192199710964 岭回归: w = [ 1.57447024 0.68161575 0.18808347 -0.04549686] , b = 50.56897681218462 Lasso回归: w = [ 1.61643393 0.72707903 0.22806763 -0. ] , b = 46.242690616035496
注:训练集:测试集=1:1,随机种子采用你学号后两位,例如你学号后两位=01,则random_state=1,如果最后两位=34,则random_state=34。最终结果输出你预测结果、实际结果以及模型得分三项。
序号 | 年龄 | 收入 | 是否为学生 | 信誉 | 购买计算机 |
---|---|---|---|---|---|
1 | <=30 | 高 | 否 | 中 | 否 |
2 | <=30 | 高 | 否 | 优 | 否 |
3 | 31-40 | 高 | 否 | 中 | 是 |
4 | >40 | 中 | 否 | 中 | 是 |
5 | >40 | 低 | 是 | 中 | 是 |
6 | >40 | 低 | 是 | 优 | 否 |
7 | 31-40 | 低 | 是 | 优 | 是 |
8 | <=30 | 中 | 否 | 中 | 否 |
9 | <=30 | 低 | 是 | 中 | 是 |
10 | >40 | 中 | 是 | 中 | 是 |
11 | <=30 | 中 | 是 | 优 | 是 |
12 | 31-40 | 中 | 否 | 优 | 是 |
13 | 31-40 | 高 | 是 | 中 | 是 |
14 | >40 | 中 | 否 | 优 | 否 |
# 导入库
import pandas as pd
from sklearn.model_selection import train_test_split
from sklearn.naive_bayes import GaussianNB
from sklearn.metrics import accuracy_score
# 定义数据集
data = {"Age": ["<=30", "<=30", "31-40", ">40", ">40", ">40", "31-40", "<=30", "<=30", ">40", "<=30",
"31-40", "31-40", ">40"],
"Income": ["high", "high", "high", "medium", "low", "low", "low", "medium", "low", "medium",
"medium", "medium", "high", "medium"],
"Student": ["no", "no", "no", "no", "yes", "yes", "yes", "no", "yes", "yes", "yes", "no", "yes",
"no"],
"Credit_rating": ["mid", "high", "mid", "mid", "mid", "high", "high", "mid", "mid", "mid", "high",
"high", "mid", "high"],
"Buy_computer": ["no", "no", "yes", "yes", "yes", "no", "yes", "no", "yes", "yes", "yes", "yes",
"yes", "no"]
}
# 将数据集转换为DataFrame格式
df = pd.DataFrame(data)
# 将字符特征转换成数值特征
df["Age"] = df["Age"].map({"<=30": 0, "31-40": 1, ">40": 2})
df["Income"] = df["Income"].map({"low": 0, "medium": 1, "high": 2})
df["Student"] = df["Student"].map({"no": 0, "yes": 1})
df["Credit_rating"] = df["Credit_rating"].map({"low": 0, "mid": 1, "high": 2})
df["Buy_computer"] = df["Buy_computer"].map({"no": 0, "yes": 1})
# 将数据集分割成训练集和测试集
X_train, X_test, y_train, y_test = train_test_split(df.drop(columns=["Buy_computer"]), df["Buy_computer"], test_size=0.5, random_state=33)
# 初始化模型
gnb = GaussianNB()
# 训练模型
gnb.fit(X_train, y_train)
# 预测测试集结果
y_pred = gnb.predict(X_test)
# 计算准确率
score = accuracy_score(y_test, y_pred)
# 输出预测结果、实际结果和模型得分
print("Predict\tActual")
for i in range(len(y_test)):
print("{}\t{}".format(y_pred[i], y_test.iloc[i]))
print("Model score:", score)
Predict Actual 1 0 1 1 1 0 1 1 1 0 1 1 1 0 Model score: 0.42857142857142855