Catch variance equal to zero when scaling

.github/workflows/check-standard.yaml

@@ -1,4 +1,4 @@
-# Workflow derived from https://github.com/r-lib/actions/tree/master/examples
+# Workflow derived from https://github.com/r-lib/actions/tree/v2/examples
 # Need help debugging build failures? Start at https://github.com/r-lib/actions#where-to-find-help
 on:
   push:
@@ -18,7 +18,7 @@ jobs:
       fail-fast: false
       matrix:
         config:
-          - {os: macOS-latest,   r: 'release'}
+          - {os: macos-latest,   r: 'release'}
           - {os: windows-latest, r: 'release'}
           - {os: ubuntu-latest,   r: 'devel', http-user-agent: 'release'}
           - {os: ubuntu-latest,   r: 'release'}
@@ -32,21 +32,24 @@ jobs:
       _R_CHECK_LENGTH_1_LOGIC2_: verbose
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
 
-      - uses: r-lib/actions/setup-pandoc@v1
+      - uses: r-lib/actions/setup-pandoc@v2
 
-      - uses: r-lib/actions/setup-r@v1
+      - uses: r-lib/actions/setup-r@v2
         with:
           r-version: ${{ matrix.config.r }}
           http-user-agent: ${{ matrix.config.http-user-agent }}
           use-public-rspm: true
 
-      - uses: r-lib/actions/setup-r-dependencies@v1
+      - uses: r-lib/actions/setup-r-dependencies@v2
         with:
-          extra-packages: rcmdcheck
+          extra-packages: any::rcmdcheck
+          needs: check
 
-      - uses: r-lib/actions/check-r-package@v1
+      - uses: r-lib/actions/check-r-package@v2
+        with:
+          upload-snapshots: true
 
       - name: Show testthat output
         if: always()

DESCRIPTION

@@ -2,8 +2,8 @@ Encoding: UTF-8
 Package: bigstatsr
 Type: Package
 Title: Statistical Tools for Filebacked Big Matrices
-Version: 1.5.13
-Date: 2023-12-13
+Version: 1.5.15
+Date: 2024-03-24
 Authors@R: c(
   person("Florian", "Privé", email = "[email protected]", 
          role = c("aut", "cre")),

NAMESPACE

@@ -68,6 +68,7 @@ exportMethods(tcrossprod)
 exportMethods(typeof)
 import(foreach)
 import(ggplot2)
+import(rmio)
 importFrom(Rcpp,sourceCpp)
 importFrom(bigassertr,assert_01)
 importFrom(bigassertr,assert_all)

NEWS.md

@@ -1,3 +1,7 @@
+## bigstatsr 1.5.14
+
+- Error when variables with a zero scaling are used in e.g. `big_randomSVD()` and `big_crossprodSelf()` (#52).
+
 ## bigstatsr 1.5.13
 
 - Add parameter `backingfile` to `big_crossprodSelf()` and `big_cor()` (#170).

R/FBM.R

@@ -110,6 +110,7 @@ sub_bk <- function(path, replacement = "", stop_if_not_ext = TRUE) {
 #' X[]  # access as standard R matrix
 #'
 #' @exportClass FBM
+#' @import rmio
 #'
 FBM_RC <- methods::setRefClass(
 

R/crossprodSelf.R

@@ -44,6 +44,8 @@ big_crossprodSelf <- function(
     tmp1 <- X[ind.row, ind.col[ind1]]
 
     ms <- fun.scaling(X, ind.row = ind.row, ind.col = ind.col[ind1])
+    if (any_near0(ms$scale)) stop2(MSG_ZERO_SCALE)
+
     mu[ind1]    <- ms$center
     delta[ind1] <- ms$scale
     sums[ind1]  <- colSums(tmp1)

R/plot.R

@@ -12,9 +12,9 @@
 #'
 #' @examples
 #' library(ggplot2)
-#' qplot(y = 1:10)
-#' qplot(y = 1:10) + theme_bw()
-#' qplot(y = 1:10) + theme_bigstatsr()
+#' (p <- ggplot(mapping = aes(x = 1:10, y = 1:10)) + geom_point())
+#' p + theme_bw()
+#' p + theme_bigstatsr()
 theme_bigstatsr <- function(size.rel = 1) {
   theme_bw() +
     theme(
@@ -31,10 +31,6 @@ theme_bigstatsr <- function(size.rel = 1) {
     )
 }
 
-MY_THEME <- function(p, coeff = 1) {
-  p + theme_bigstatsr(size.rel = coeff)
-}
-
 #' @importFrom cowplot plot_grid
 #' @export
 cowplot::plot_grid
@@ -101,7 +97,9 @@ plot.big_SVD <- function(x, type = c("screeplot", "scores", "loadings"),
 
     assert_lengths(nval, 1)
 
-    p <- MY_THEME(qplot(y = x$d[seq_len(nval)]), coeff = coeff) +
+    p <- ggplot(mapping = aes(x = seq_len(nval), y = x$d[seq_len(nval)])) +
+      theme_bigstatsr(size.rel = coeff) +
+      geom_point() +
       geom_line() +
       scale_y_log10() +
       labs(title = "Scree Plot", x = "PC Index", y = "Singular Value")
@@ -133,7 +131,9 @@ plot.big_SVD <- function(x, type = c("screeplot", "scores", "loadings"),
         nx <- scores[1]
         ny <- scores[2]
 
-        MY_THEME(qplot(x = sc[, nx], y = sc[, ny]), coeff = coeff) +
+        ggplot(mapping = aes(x = sc[, nx], y = sc[, ny])) +
+          geom_point() +
+          theme_bigstatsr(size.rel = coeff) +
           coord_fixed() +
           labs(title = "Scores of PCA", x = paste0("PC", nx), y = paste0("PC", ny))
 
@@ -155,7 +155,9 @@ plot.big_SVD <- function(x, type = c("screeplot", "scores", "loadings"),
 
     } else {
 
-      p <- MY_THEME(qplot(y = x$v[, loadings]), coeff = coeff) +
+      p <- ggplot(mapping = aes(x = rows_along(x$v), y = x$v[, loadings])) +
+        geom_point() +
+        theme_bigstatsr(size.rel = coeff) +
         labs(title = paste0("Loadings of PC", loadings),
              x = "Column index", y = NULL)
 
@@ -215,17 +217,20 @@ plot.mhtest <- function(x, type = c("hist", "Manhattan", "Q-Q", "Volcano"),
   type <- match.arg(type)
   main <- paste(type, "plot")
 
-  if (type == "Manhattan") {
-    qplot(y = -lpval) +
+  p <- if (type == "Manhattan") {
+    ggplot(mapping = aes(x = seq_along(lpval), y = -lpval)) +
+      geom_point() +
       labs(title = main, x = "Column Index",
            y = expression(-log[10](italic("p-value"))))
   } else if (type == "Volcano") {
-    qplot(x = x[["estim"]], y = -lpval) +
+    ggplot(mapping = aes(x = x[["estim"]], y = -lpval)) +
+      geom_point() +
       labs(title = main, x = "Estimate",
            y = expression(-log[10](italic("p-value"))))
   } else if (type == "Q-Q") {
     unif.ranked <- stats::ppoints(length(lpval))[rank(lpval)]
-    qplot(x = -log10(unif.ranked), y = -lpval) +
+    ggplot(mapping = aes(x = -log10(unif.ranked), y = -lpval)) +
+      geom_point() +
       labs(title = main,
            x = expression(Expected~~-log[10](italic("p-value"))),
            y = expression(Observed~~-log[10](italic("p-value")))) +
@@ -239,7 +244,7 @@ plot.mhtest <- function(x, type = c("hist", "Manhattan", "Q-Q", "Volcano"),
       labs(x = "p-value")
   }
 
-  last_plot() + theme_bigstatsr(size.rel = coeff)
+  p + theme_bigstatsr(size.rel = coeff)
 }
 
 ################################################################################

R/randomSVD.R

@@ -13,7 +13,7 @@
 
   Ax   <- FBM(n, ncores)
   Atx  <- FBM(m, 1)
-  calc <- FBM(ncores, 1, init = 0)
+  calc <- FBM(ncores, 1, init = -1)
 
   cluster_type <- getOption("bigstatsr.cluster.type")
   if (verbose) {
@@ -26,24 +26,32 @@
 
     if (ic == 0) { # I'm the master
 
+      # Wait for the slaves to finish computing the scalings
+      while (any(calc[] < 0)) {
+        if (any(calc[] == -2)) {
+          calc[] <- 3  # signal all slaves to stop
+          stop2(MSG_ZERO_SCALE)
+        } else Sys.sleep(TIME)
+      }
+
       printf <- function(...) cat(sprintf(...))
       it <- 0
       # A
       A <- function(x, args) {
         printf("%d - computing A * x\n", it <<- it + 1)
         Atx[] <- x
         calc[] <- 1  # make them work
-        # Master wait for its slaves to finish working
-        while (sum(calc[]) > 0) Sys.sleep(TIME)
+        # the master wait for its slaves to finish working
+        while (any(calc[] > 0)) Sys.sleep(TIME)
         rowSums(Ax[])
       }
       # Atrans
       Atrans <- function(x, args) {
         printf("%d - computing At * x\n", it <<- it + 1)
         Ax[, 1] <- x
         calc[] <- 2  # make them work
-        # Master wait for its slaves to finish working
-        while (sum(calc[]) > 0) Sys.sleep(TIME)
+        # the master wait for its slaves to finish working
+        while (any(calc[] > 0)) Sys.sleep(TIME)
         Atx[]
       }
 
@@ -61,6 +69,12 @@
 
       # Scaling
       ms <- fun.scaling(X, ind.row = ind.row, ind.col = ind.col.part)
+      if (any_near0(ms$scale)) {
+        calc[ic] <- -2  # signal the master there is an issue with the scaling
+        return(ms)
+      } else {
+        calc[ic] <- 0
+      }
 
       repeat {
         # Slaves wait for their master to give them orders
@@ -78,8 +92,6 @@
         } else if (c == 3) {
           # End
           break
-        } else {
-          stop("RandomSVD: unclear order from the master.")
         }
         calc[ic] <- 0
       }
@@ -110,6 +122,7 @@
 
   # scaling
   ms <- fun.scaling(X, ind.row, ind.col)
+  if (any_near0(ms$scale)) stop2(MSG_ZERO_SCALE)
 
   printf <- function(...) if (verbose) cat(sprintf(...))
   it <- 0

R/scaling.R

@@ -55,6 +55,8 @@ big_scale <- function(center = TRUE, scale = TRUE) {
       sds <- rep(1, m)
     }
 
+    if (any_near0(sds)) warning2(MSG_ZERO_SCALE)
+
     data.frame(center = means, scale = sds)
   }
 }

R/tcrossprodSelf.R

@@ -42,6 +42,8 @@ big_tcrossprodSelf <- function(
     ind <- seq2(intervals[j, ])
     ind.col.ind <- ind.col[ind]
     ms <- fun.scaling(X, ind.row = ind.row, ind.col = ind.col.ind)
+    if (any_near0(ms$scale)) stop2(MSG_ZERO_SCALE)
+
     means[ind] <- ms$center
     sds[ind]   <- ms$scale
     increment_scaled_tcrossprod(K, X_part_temp, X,

R/utils-assert.R

@@ -4,6 +4,17 @@
 
 ################################################################################
 
+MSG_ZERO_SCALE <-
+  "Some variables have zero scaling; remove them before attempting to scale."
+
+################################################################################
+
+any_near0 <- function(x) {
+  any(dplyr::near(x, 0))
+}
+
+################################################################################
+
 as_vec <- function(x) {
   x2 <- drop(x)
   if (is.matrix(x2))

inst/WORDLIST

@@ -26,10 +26,12 @@ bty
 cbind
 cdot
 CMSA
+Codecov
 confounders
 Crossprod
 crossprods
 didn
+dir
 doesn
 doi
 eigen

tests/testthat/helper-init.R

@@ -55,6 +55,14 @@ diffPCs <- function(test, rot) {
 
 ################################################################################
 
+custom_scaling <- function(X, ind.row = rows_along(X),
+                           ind.col = cols_along(X), ncores = 1) {
+  stats <- big_colstats(X, ind.row, ind.col, ncores = ncores)
+  data.frame(center = stats$sum / length(ind.row), scale = sqrt(stats$var))
+}
+
+################################################################################
+
 set.seed(NULL)
 if (not_cran) {
   # Seeds that won't work (because of bad luck)

tests/testthat/test-crossprodSelf.R

@@ -76,3 +76,15 @@ test_that("equality with crossprod with half of the data", {
 })
 
 ################################################################################
+
+test_that("we catch zero variance variables when scaling", {
+
+  X <- FBM(20, 20, init = rnorm(400))
+  expect_no_error(big_crossprodSelf(X, fun.scaling = custom_scaling))
+
+  X[, 1] <- 0
+  expect_error(big_crossprodSelf(X, fun.scaling = custom_scaling),
+               "Some variables have zero scaling")
+})
+
+################################################################################

tests/testthat/test-randomSVD.R

@@ -138,3 +138,22 @@ test_that("as_scaling_fun() works", {
 })
 
 ################################################################################
+
+test_that("zero variance is caught", {
+
+  X <- FBM(20, 20, init = rnorm(400))
+  expect_no_error(big_randomSVD(X, big_scale()))
+
+  X[, 1] <- 0  # set a variable to have zero variance
+  # this is also catched as a warning in big_scale()
+  expect_error(expect_warning(big_randomSVD(X, big_scale()),
+                              "Some variables have zero scaling"),
+               "Some variables have zero scaling")
+
+  expect_error(big_randomSVD(X, custom_scaling),
+               "Some variables have zero scaling")
+  expect_error(big_randomSVD(X, custom_scaling, ncores = test_cores()),
+               "Some variables have zero scaling")
+})
+
+################################################################################