在 R 中将数据帧转换为 cor.mat 数据类型

Question

我有一个属于数据帧数据类型的相关矩阵。

#creates correlation matrix of dataframe data type

eff_1971 <- c(NA, .56, .25, .25, .22, -.47, -.01, -.06)
eff_1972 <- c(.56, NA, .23, .23, .25, .47, -.01, .03)
annual_earnings_1970 <- c(.25, .23, NA, .88, .83, -.02, -.28, -.14)
annual_earnings_1971 <- c(.25, .23, .88, NA, .88, -.02, .21, -.29)
annual_earnings_1972 <- c(.22, .25, .83, .88, NA, .03, .06, .21)
change_eff_1971_1972 <- c(-.47, .47, -.02, -0.02, 0.03, NA, 0.0, .1)
change_ann_earn_1970_1971 <- c(-.01, -.01, -.28, .21, .06, 0.0, NA, -.29)
change_ann_earn_1971_1972 <- c(-.06, .03, -.14, -.29, .21, .10, -.29, NA)
df <- data.frame(eff_1971, 
                 eff_1972, 
                 annual_earnings_1970,
                 annual_earnings_1971,
                 annual_earnings_1972,
                 change_eff_1971_1972,
                 change_ann_earn_1970_1971,
                 change_ann_earn_1971_1972)
rownames(df) <- c("eff_1971","eff_1972","annual_earnings_1970",
                  "annual_earnings_1971", "annual_earnings_1972", "change_eff_1971_1972",
                  "change_ann_ear_1970_1971", "change_ann_earn_1971_1972")

如何将其转换为 cor.mat 数据类型？我想使用 cor2cov 将此相关矩阵转换为协方差矩阵。

非常感谢！