正如Martin所建议的，在这种情况下，expand.grid是您的朋友。由于你没有提供数据，我创建了一些。以下可能不是最优雅的解决方案，但它应该给予你一个想法，你可以扩展。

# Using double letters so as to not overwrite "c"
factors <- c("aa", "bb", "cc")
# Create permutation list. Set stringsAsFactors to FALSE so we can use "get"
# later.
f2 <- expand.grid(factors, factors, stringsAsFactors = FALSE)
# Order on column 1
f2 <- f2[order(f2[, 1L]), ]
# Augment with correlation data.
set.seed(61L)
n <- 10000L
rho <- 0.7
aa <- rnorm(n, 0, 1)
bb <- rnorm(n, 0, 1)
cc <- rho * aa + sqrt(1 - rho ^ 2) * bb
# Always preallocate your return object if you can.
f2$cor <- 0
# Calculate correlations
for (i in seq_len(nrow(f2))) {
  f2$Cor[i] <- cor(get(f2$Var1[i]), get(f2$Var2[i]))
}

# Create Matrix
corM <- matrix(f2$Cor, ncol = 3L, dimnames = list(factors, factors))

corM
aa  1.00000000 -0.01064047 0.6978159
bb -0.01064047  1.00000000 0.7088116
cc  0.69781586  0.70881156 1.0000000

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