for循环中没有实现cbind命令

Question

我的代码和数据类似于以下示例（在R中），但在下面的代码中，cbind命令未在for循环中实现，并且最终t1未添加到A，因为列数是不相等。请帮我。

test <- data.frame(c(2, 3), 
                   c("b", "a"), 
                   c("f", "t"), 
                   c("T", "F"))
names(test) <- c("x", "y", "d", "L")

A <- data.frame(c(1, 2, 3), 
                c("a", "b", "c"), 
                c("f", "f", "t"),
                c("T", "T", "F"),
                 c(2, 2, 3))
names(A) <- c("x", "y", "d", "L", "n")

for (i in 1:nrow(test)) {
  t1 <- test[i, ]
  if (t1$d == "f") {
    A_reduct <- A[, c(1:2)]
    test_reduct <- test[, c(1:2)]
    mix_test_A <- rbind(A_reduct, test_reduct)
    dist_mix_test_A <- as.matrix(FD::gowdis(mix_test_A))
    idxs_mix_test_A <- KernelKnn::distMat.knn.index.dist(
        dist_mix_test_A, 
        TEST_indices = c(4:5), 
        k = 1, 
        threads = 1, 
        minimize = T
    )
    nn_test_A <- idxs_mix_test_A$test_knn_idx
    x <- nn_test_A[i]
    lbltest <- test[i, 4]
    lblgroup <- A[x, 4]
    if (lbltest == lblgroup) {
      y <- A[x, 5]
      t1 <- cbind(t1, n = y)
      A <- rbind(A, t1)
    }
  }
}