How to replace values in a data frame using R language?

In R language, you can use the substitute() function to replace values in a data frame. The specific steps are as follows:

1. Select one or more columns to replace in the data frame.
2. Use conditional statements or logical operators to filter the selected columns, in order to obtain the row index that needs to be replaced.
3. replace

Here is an example code demonstrating how to use R language to replace values in a data frame.

# 创建一个示例数据框
df <- data.frame(A = c(1, 2, 3, 4),
                 B = c("apple", "banana", "apple", "banana"))

# 查看原始数据框
print(df)

# 替换数据框中 B 列中值为 "apple" 的行的 A 列的值为 10
df$A[df$B == "apple"] <- 10

# 查看替换后的数据框
print(df)

By running the above code, you can see that the values in column A of the original dataframe have been replaced with 10 for the rows where column B contains the value “apple.”