基于另一列中的值子集的多个列的条件替换行值

Question

Ok this should be simple and I am aware of many questions similar to this that have been answered but none of the answers are working for my data.

Here is some quick example data to illustrate my point:

Soil <- c("Organic - 10", "Organic - 12", "Sand - 6", "Silt - 6", "Silt - 6")
Value1 <- c(2, 5, 1, 4, 6)
Value2 <- c(45, 21, 776, 2, 6)
X03 <- c(4, 23, 45, 12, 23)
X04 <- c(56, 2, 7, 34, 65)

DF <- data.frame(Soil, Value1, Value2, X03, X04)

Basically what I want to do is replace the values of X02 and X03 with 0 for the rows where Soil is "Organic".

My initial thought was to do the following:

# create index of the columns in whcih values are to be changed
index <- grep("^X0", colnames(DF))
# Use ifelse statement to change values conditionally
DF[,c(index)] <- ifelse(grepl("^Organic", DF$Soil), 0, DF[index])

This however gives the following warning and replaces all values with 0 in X03 and X04:

Warning message:
In `[<-.data.frame`(`*tmp*`, , c(index), value = list(0, 0, c(4,  :
  provided 5 variables to replace 2 variables

Any ideas appreciated.

Answer 1

尝试

DF[grepl("^Organic", DF$Soil),index]<-0