Warning: file_get_contents(/data/phpspider/zhask/data//catemap/4/r/78.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181

Warning: file_get_contents(/data/phpspider/zhask/data//catemap/9/loops/2.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
R 使用循环将计算变量添加到数据集_R_Loops_Variables - Fatal编程技术网

R 使用循环将计算变量添加到数据集

R 使用循环将计算变量添加到数据集,r,loops,variables,R,Loops,Variables,我已经检查过是否有人问过这个问题,但大多数答案都是关于使用向量的,我希望在理解循环之后解决这个问题 varlist <- c("var1", "var2", "var3", "var4") for (i in varlist){ Zscore<-(df$i - mean(df$i[df$time == 0], na.rm = T) ) / sd(df$i[df$time == 0], na.rm = TRUE) df[,paste0(i,"_Standard")

我已经检查过是否有人问过这个问题,但大多数答案都是关于使用向量的,我希望在理解循环之后解决这个问题

varlist <- c("var1", "var2", "var3", "var4")

for (i in varlist){
    Zscore<-(df$i - mean(df$i[df$time == 0], na.rm = T) ) /  sd(df$i[df$time == 0], na.rm = TRUE) 
    df[,paste0(i,"_Standard")] <- Zscore
}

varlist将
df$i
更改为
df[[i]]
谢谢!在
[.data.frame(df,I):未定义的列被选中时,没有人告诉我错误。
当我使用
varlist分配列时