> set.seed(1)> x  <- matrix(rnorm(200), nrow=20)> p1 <- prcomp_irlba(x, n=3)> summary(p1)Importance of components%s:                         PC1    PC2    PC3Standard deviation     1.541 1.2513 1.1916Proportion of Variance 0.443 0.2921 0.2649Cumulative Proportion  0.443 0.7351 1.0000> p2 <- prcomp(x, tol=0.7)> summary(p2)Importance of first k=3 (out of 10) components:                          PC1    PC2    PC3Standard deviation     1.5411 1.2513 1.1916Proportion of Variance 0.2806 0.1850 0.1678Cumulative Proportion  0.2806 0.4656 0.6334