r - 如何添加具有相同名称的列

Question

我有很大的数据集，即两个数据框。并想要添加在另一个数据框中具有相同列名的值。我该如何设置代码？

df1
a b c
0 0 0
0 0 0

df2
a c d
1 1 0
0 1 0

我期望的是:

a b c
1 0 1
0 0 1

这意味着我负责保留 colnames df1，但值在 df2 中。谢谢您的帮助。祝你有美好的一天

Answer 1

1. 与data.frame配合使用

    data.frame(lapply(X = split.default(x = cbind(df1, df2),
                                        f = c(names(df1), names(df2))),
                      FUN =  rowSums))[names(df1)]
    #  a b c
    #1 1 0 1
    #2 0 0 1

适用于data.frame和matrix

    nm = intersect(colnames(df1), colnames(df2))
    nm1 = colnames(df1)[!colnames(df1) %in% nm]

    m = cbind(df1[, nm1, drop = FALSE], df1[, nm, drop = FALSE] + df2[, nm, drop = FALSE])
    colnames(m) = c(nm1, nm)
    m[,colnames(df1)]
    #  a b c
    #1 1 0 1
    #2 0 0 1

---

#DATA
df1 = structure(list(a = c(0L, 0L), b = c(0L, 0L), c = c(0L, 0L)),
                class = "data.frame",
                row.names = c(NA, -2L))

df2 = structure(list(a = 1:0, c = c(1L, 1L), d = c(0L, 0L)),
                class = "data.frame",
                row.names = c(NA, -2L))