I have a very large data frame of sales data (df8). When loading in, some of the variables that I want to be numeric loaded as chr. I want to change every column where the colname contains the word "Order" from chr to numeric. How can I do this?
我有一个非常大的销售数据数据框（df8）。加载时，我希望将一些变量数字加载为chr。我想将colname包含单词“Order”的每一列从chr更改为numeric。我怎样才能做到这一点？
1 个解决方案
#1
1
I would use function grepl to find the occurrences of "order" and go through each column and convert to numeric. Notice that the variables are actually characters and it won't work if your data is a factor (that will need (as.numeric(as.character(x))).
我会使用函数grepl来查找“order”的出现并遍历每一列并转换为numeric。请注意，变量实际上是字符，如果您的数据是一个因素（需要（as.numeric（as.character（x））），它将无法工作。
# create data.frame with characters
xy <- data.frame(a = runif(5), b.order = runif(5), cOrder = runif(5))
xy[, c(2, 3)] <- sapply(xy[, c(2, 3)], FUN = as.character)
str(xy)
'data.frame': 5 obs. of 3 variables:
$ a : num 0.914 0.468 0.106 0.624 0.841
$ b.order: chr "0.363523897947744" "0.56488766730763" "0.42081760126166" "0.560672372812405" ...
$ cOrder : chr "0.949268750846386" "0.596737345447764" "0.368769273394719" "0.717566329054534" ...
with.order <- grepl("order", names(xy), ignore.case = TRUE)
xy[, with.order] <- sapply(xy[, with.order], FUN = as.numeric)
str(xy)
'data.frame': 5 obs. of 3 variables:
$ a : num 0.914 0.468 0.106 0.624 0.841
$ b.order: num 0.364 0.565 0.421 0.561 0.768
$ cOrder : num 0.949 0.597 0.369 0.718 0.417
#1
1
I would use function grepl to find the occurrences of "order" and go through each column and convert to numeric. Notice that the variables are actually characters and it won't work if your data is a factor (that will need (as.numeric(as.character(x))).
我会使用函数grepl来查找“order”的出现并遍历每一列并转换为numeric。请注意，变量实际上是字符，如果您的数据是一个因素（需要（as.numeric（as.character（x））），它将无法工作。
# create data.frame with characters
xy <- data.frame(a = runif(5), b.order = runif(5), cOrder = runif(5))
xy[, c(2, 3)] <- sapply(xy[, c(2, 3)], FUN = as.character)
str(xy)
'data.frame': 5 obs. of 3 variables:
$ a : num 0.914 0.468 0.106 0.624 0.841
$ b.order: chr "0.363523897947744" "0.56488766730763" "0.42081760126166" "0.560672372812405" ...
$ cOrder : chr "0.949268750846386" "0.596737345447764" "0.368769273394719" "0.717566329054534" ...
with.order <- grepl("order", names(xy), ignore.case = TRUE)
xy[, with.order] <- sapply(xy[, with.order], FUN = as.numeric)
str(xy)
'data.frame': 5 obs. of 3 variables:
$ a : num 0.914 0.468 0.106 0.624 0.841
$ b.order: num 0.364 0.565 0.421 0.561 0.768
$ cOrder : num 0.949 0.597 0.369 0.718 0.417