使用for循环将列名从大写转换为小写
我希望使用for循环将列名转换为小写使用for循环将列名从大写转换为小写,r,R,我希望使用for循环将列名转换为小写 df <- structure(list(a = c(1, 2), b = c(2, 3)), .Names = c("a", "b" ), row.names = c(NA, -2L), class = "data.frame") 请告诉我哪里弄错了,谢谢。您应该能够使用for循环来完成此操作,循环的列名称数为: for (i in 1:length(colnames(df))) { colnames(df)[i] = toupper(co
df <- structure(list(a = c(1, 2), b = c(2, 3)), .Names = c("a", "b"
), row.names = c(NA, -2L), class = "data.frame")
请告诉我哪里弄错了,谢谢。您应该能够使用
for
循环来完成此操作,循环的列名称数为:
for (i in 1:length(colnames(df))) {
colnames(df)[i] = toupper(colnames(df)[i])
# return() ... you don't need this
}
他比我跑得快。您也可以跳过
长度(colnames(df))
:
for(1中的i:ncol(df)){
colnames(df)[i]df[i]
与df
是一个不同的对象。而colnames为什么要在循环中执行此操作?这根本不应该在Rjantitor::clean_names()中使用for循环(在CRAN和此处)
for( i in colnames(df)){
colnames(df[i]) = toupper(i)
return()
}
for (i in 1:length(colnames(df))) {
colnames(df)[i] = toupper(colnames(df)[i])
# return() ... you don't need this
}
for( i in 1:ncol(df)){
colnames(df)[i] <- toupper(colnames(df)[i])
}
for( i in colnames(df)){
colnames(df)[which(colnames(df)==i)] = toupper(i)
}
df
A B
1 1 2
2 2 3