摘要：#设置小数点后位数options(digits=2)name=c("John Davis","Angela Williams","Bullwinkle Moose", "David Jones","Janice Markhammer","Cheryl Cushing","Reuven Ytzrhak", "Greg Knox","Joel England","Mary Rayburn")math= 阅读全文

摘要：1.数据的产生在直线y=2x+5的基础上，加上服从正态分布的噪声。产生20对(x,y)的训练集。2，模型设回归方程为y=a*x+b，其中a,b为回归系数，利用梯度下降算法求解系数a,b的值代码如下：train_x=c(1:20)train_y=2*train_x+5train_error=rnorm(20,mean=0,sd=2)train_y=train_y+train_errorplot(train_x,train_y,col="red",pch=19,main="x与y的关系图")#abline(lm(train_y~train_x),col=&q 阅读全文

摘要：利用给定的数据预测某天（"Sunny","Cool","High","Strong"）是否打球……数据：NO Outlook Temperature Humidity Wind Play1 Sunny Hot High Weak No2 Sunny Hot High Strong No3 Overcast Hot High Weak Yes4 Rain Mild High Weak Yes5 Rain Cool Normal Weak Yes6 Rain Cool Normal Strong No7 Overcas 阅读全文

摘要：循环语句 a,for语句格式：for(var in seq) statement b,while语句格式：while(cond) statement c,repeat语句 格式：repeatstatement当遇到break后结束例子： forsum=0seq=c(1:100)for(i in seq){ sum=sum+i}print(sum)whilesum=0i=100while(i>0){ sum=sum+i i=i-1}print(sum)repeati=100sum=0repeat { if(i==0) break sum=i+sum i=i-1}print(su... 阅读全文