fifelse() coerces NA to other types and supports vectorized na argume…

…nt (#4289)
Rdatatable · May 14, 2021 · 03dff91 · 03dff91
1 parent 9847445
commit 03dff91
Show file tree

Hide file tree

Showing 4 changed files with 155 additions and 80 deletions.
diff --git a/NEWS.md b/NEWS.md
@@ -91,6 +91,8 @@
 
 12. Typo checking in `i` available since 1.11.4 is extended to work in non-English sessions, [#4989](https://github.com/Rdatatable/data.table/issues/4989). Thanks to Michael Chirico for the PR.
 
+13. `fifelse()` now coerces logical `NA` to other types and the `na` argument supports vectorized input, [#4277](https://github.com/Rdatatable/data.table/issues/4277) [#4286](https://github.com/Rdatatable/data.table/issues/4286) [#4287](https://github.com/Rdatatable/data.table/issues/4287). Thanks to @michaelchirico and @shrektan for reporting, and @shrektan for implementing.
+
 ## BUG FIXES
 
 1. `by=.EACHI` when `i` is keyed but `on=` different columns than `i`'s key could create an invalidly keyed result, [#4603](https://github.com/Rdatatable/data.table/issues/4603) [#4911](https://github.com/Rdatatable/data.table/issues/4911). Thanks to @myoung3 and @adamaltmejd for reporting, and @ColeMiller1 for the PR. An invalid key is where a `data.table` is marked as sorted by the key columns but the data is not sorted by those columns, leading to incorrect results from subsequent queries.

diff --git a/inst/tests/tests.Rraw b/inst/tests/tests.Rraw
@@ -15859,7 +15859,7 @@ test(2072.009, fifelse(test_vec, rep(1L,11L), rep(0L,10L)),      error="Length o
 test(2072.010, fifelse(test_vec, rep(1,10L), rep(0,11L)),        error="Length of 'yes' is 10 but must be 1 or length of 'test' (11).")
 test(2072.011, fifelse(test_vec, rep(TRUE,10L), rep(FALSE,10L)), error="Length of 'yes' is 10 but must be 1 or length of 'test' (11).")
 test(2072.012, fifelse(0:1, rep(TRUE,2L), rep(FALSE,2L)),        error="Argument 'test' must be logical.")
-test(2072.013, fifelse(test_vec, TRUE, "FALSE"),                 error="'yes' is of type logical but 'no' is of type character. Please")
+test(2072.013, fifelse(test_vec, TRUE, "FALSE"),                 error="'no' is of type character but 'yes' is logical. Please")
 test(2072.014, fifelse(test_vec, list(1),list(2,4)),             error="Length of 'no' is 2 but must be 1 or length of 'test' (11).")
 test(2072.015, fifelse(test_vec, list(1,3),list(2,4)),           error="Length of 'yes' is 2 but must be 1 or length of 'test' (11).")
 test(2072.016, fifelse(test_vec, list(1), list(0)), as.list(as.numeric(out_vec)))
@@ -15885,7 +15885,7 @@ test(2072.031, fifelse(test_vec_na, "1", rep("0",12L)), as.character(out_vec_na)
 test(2072.032, fifelse(test_vec_na, rep("1",12L), "0"), as.character(out_vec_na))
 test(2072.033, fifelse(test_vec_na, rep("1",12L), rep("0",12L)), as.character(out_vec_na))
 test(2072.034, fifelse(test_vec_na, "1", "0"), as.character(out_vec_na))
-test(2072.035, fifelse(test_vec, as.Date("2011-01-01"), FALSE), error="'yes' is of type double but 'no' is of type logical. Please")
+test(2072.035, fifelse(test_vec, as.Date("2011-01-01"), FALSE), error="'no' is of type logical but 'yes' is double. Please")
 test(2072.036, fifelse(test_vec_na, 1+0i, 0+0i), as.complex(out_vec_na))
 test(2072.037, fifelse(test_vec_na, rep(1+0i,12L), 0+0i), as.complex(out_vec_na))
 test(2072.038, fifelse(test_vec_na, rep(1+0i,12L), rep(0+0i,12L)), as.complex(out_vec_na))
@@ -16322,7 +16322,7 @@ test(2100.03, fifelse(test_vec_na, TRUE, FALSE, TRUE), as.logical(out_vec_na))
 test(2100.04, fifelse(test_vec_na, "1", "0","2"), as.character(out_vec_na))
 test(2100.05, fifelse(test_vec_na, 1+0i, 0+0i, 2+0i), as.complex(out_vec_na))
 test(2100.06, fifelse(c(TRUE,FALSE,NA), list(1:5), list(5:1), list(15:11)), list(1:5,5:1,15:11))
-test(2100.07, fifelse(test_vec_na, 1, 0, 2L), error = "'yes' is of type double but 'na' is of type integer. Please make sure that both arguments have the same type.")
+test(2100.07, fifelse(test_vec_na, 1, 0, 2L), c(1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 2)) # corece na
 test(2100.08, fifelse(test_vec_na, 1, 0, c(2,3)), error = "Length of 'na' is 2 but must be 1")
 test(2100.09, fifelse(date_vec_na, as.Date("2019-08-31"), as.Date("2019-08-30"), as.Date("2019-08-29")), as.Date(c(18139, 18138, 18138, 18138, 18138, 18137), origin = '1970-01-01'))
 test(2100.10, fifelse(date_vec_na, as.Date("2019-08-31"), as.Date("2019-08-30"), 18137), error = "'yes' has different class than 'na'. Please make sure that both arguments have the same class.")
@@ -17600,3 +17600,21 @@ test(2186, DT[, if (TRUE) .(a=1L) else .(a=1L, b=2L)], DT,
 DT = setDT(replicate(getOption('width'), 1, simplify = FALSE))
 test(2187, {print(DT, col.names='none'); TRUE}, notOutput="V")
 
+# fifelse now supports vector na arguments and coerces NA to other types, PR#4289
+test(2188.01, fifelse(c(TRUE, FALSE, TRUE, NA), 1L, 2L, 1.0), c(1, 2, 1, 1))
+test(2188.02, fifelse(c(TRUE, FALSE, TRUE, NA), 1, 2, 1L), c(1, 2, 1, 1))
+test(2188.03, fifelse(c(TRUE, FALSE, TRUE, NA), 1:4, 11:14, 101:104), c(1L, 12L, 3L, 104L))
+test(2188.04, fifelse(c(TRUE, FALSE, TRUE, NA), NA, 11:14, 101:104), c(NA, 12L, NA, 104L))
+test(2188.05, fifelse(c(TRUE, FALSE, TRUE, NA), 1:4, NA, 101:104), c(1L, NA, 3L, 104L))
+test(2188.06, fifelse(c(TRUE, FALSE, TRUE, NA), 1:4, 11:14, NA), c(1L, 12L, 3L, NA))
+test(2188.07, fifelse(c(TRUE, FALSE, TRUE, NA), 1:4, NA, NA), c(1L, NA, 3L, NA))
+test(2188.08, fifelse(c(TRUE, FALSE, TRUE, NA), NA, NA, NA), c(NA, NA, NA, NA))
+test(2188.09, fifelse(c(TRUE, FALSE, TRUE, NA), NA, NA, NA_character_), rep(NA_character_, 4L))
+test(2188.10, fifelse(c(TRUE, FALSE, TRUE, NA), NA, NA, 101:104), c(NA, NA, NA, 104L))
+test(2188.11, fifelse(c(TRUE, FALSE, TRUE, NA), NA, 11:14, NA), c(NA, 12L, NA, NA))
+test(2188.12, fifelse(c(TRUE, FALSE, TRUE, NA), NA, NA, as.Date("2020-01-01")), as.Date(c(NA, NA, NA, "2020-01-01")))
+test(2188.13, fifelse(TRUE, 1L, 2.0, "a"), error="'na' is of type character but 'no' is double. Please") # smart error message
+test(2188.14, fifelse(TRUE, NA, 2, as.Date("2019-07-07")),  error="'no' has different class than 'na'. Please")
+test(2188.15, fifelse(TRUE, NA, factor('a'), factor('a', levels = c('a','b'))), error="'no' and 'na' are both type factor but their levels are different")
+test(2188.16, fifelse(c(NA, NA), 1L, 2L, NULL), c(NA_integer_, NA_integer_)) # NULL `na` is treated as NA 
+
diff --git a/man/fifelse.Rd b/man/fifelse.Rd
@@ -11,10 +11,10 @@
 \arguments{
   \item{test}{ A logical vector. }
   \item{yes, no}{ Values to return depending on \code{TRUE}/\code{FALSE} element of \code{test}. They must be the same type and be either length \code{1} or the same length of \code{test}. }
-  \item{na}{ Value to return if an element of \code{test} is \code{NA}. It must be the same type as \code{yes} and \code{no} and length \code{1}. Default value \code{NA}. \code{NULL} is treated as \code{NA}. }
+  \item{na}{ Value to return if an element of \code{test} is \code{NA}. It must be the same type as \code{yes} and \code{no} and its length must be either \code{1} or the same length of \code{test}. Default value \code{NA}. \code{NULL} is treated as \code{NA}. }
 }
 \details{
-In contrast to \code{\link[base]{ifelse}} attributes are copied from \code{yes} to the output. This is useful when returning \code{Date}, \code{factor} or other classes.
+In contrast to \code{\link[base]{ifelse}} attributes are copied from the first non-\code{NA} argument to the output. This is useful when returning \code{Date}, \code{factor} or other classes.
 }
 \value{
 A vector of the same length as \code{test} and attributes as \code{yes}. Data values are taken from the values of \code{yes} and \code{no}, eventually \code{na}.

diff --git a/src/fifelse.c b/src/fifelse.c
@@ -11,127 +11,182 @@ SEXP fifelseR(SEXP l, SEXP a, SEXP b, SEXP na) {
   const int64_t len0 = xlength(l);
   const int64_t len1 = xlength(a);
   const int64_t len2 = xlength(b);
+  const int64_t len3 = xlength(na);
   SEXPTYPE ta = TYPEOF(a);
   SEXPTYPE tb = TYPEOF(b);
-  int nprotect = 0;
+  SEXPTYPE tn = TYPEOF(na);
+  // na_a/b/n means a scalar NA (or NULL for the na argument), which is considered to be coerced into other types
+  bool na_a = len1==1 && ta==LGLSXP && LOGICAL(a)[0]==NA_LOGICAL;
+  bool na_b = len2==1 && tb==LGLSXP && LOGICAL(b)[0]==NA_LOGICAL;
+  bool na_n = isNull(na) || (len3==1 && tn==LGLSXP && LOGICAL(na)[0]==NA_LOGICAL);
 
-  if (ta != tb) {
-    if (ta == INTSXP && tb == REALSXP) {
-      SEXP tmp = PROTECT(coerceVector(a, REALSXP)); nprotect++;
-      a = tmp;
+  if (!na_a && len1!=1 && len1!=len0)
+    error(_("Length of 'yes' is %"PRId64" but must be 1 or length of 'test' (%"PRId64")."), len1, len0);
+  if (!na_b && len2!=1 && len2!=len0)
+    error(_("Length of 'no' is %"PRId64" but must be 1 or length of 'test' (%"PRId64")."), len2, len0);
+  if (!na_n && len3!=1 && len3!=len0)
+    error(_("Length of 'na' is %"PRId64" but must be 1 or length of 'test' (%"PRId64")."), len3, len0);
+
+  int nprotect = 0;
+  SEXPTYPE tans = !na_a ? ta : !na_b ? tb : !na_n ? tn : LGLSXP;
+  if (!(na_a && na_b && na_n)) {
+    SEXPTYPE ta0 = ta, tb0 = tb, tn0 = tn; // record the original type for error message use
+    if (!na_b && tans==INTSXP && tb==REALSXP) tans = tb;
+    if (!na_n && tans==INTSXP && tn==REALSXP) tans = tn;
+    if (!na_a && tans==REALSXP && ta==INTSXP) {
+      a = PROTECT(coerceVector(a, REALSXP)); nprotect++;
       ta = REALSXP;
-    } else if (ta == REALSXP && tb == INTSXP) {
-      SEXP tmp = PROTECT(coerceVector(b, REALSXP)); nprotect++;
-      b = tmp;
+    }
+    // it's not possible that non-NA `yes`' type will be different from `tans`
+    if (!na_b && tans==REALSXP && tb==INTSXP) {
+      b = PROTECT(coerceVector(b, REALSXP)); nprotect++;
       tb = REALSXP;
-    } else {
-      error(_("'yes' is of type %s but 'no' is of type %s. Please make sure that both arguments have the same type."), type2char(ta), type2char(tb));
     }
+    if (!na_b && tans != tb) 
+      error(_("'no' is of type %s but '%s' is %s. Please make all arguments have the same type."), type2char(tb0), tans==ta0 ? "yes" : "na", tans==ta0 ? type2char(ta0) : type2char(tn0));
+    if (!na_n && tans==REALSXP && tn==INTSXP) {
+      na = PROTECT(coerceVector(na, REALSXP)); nprotect++;
+      tn = REALSXP;
+    }
+    if (!na_n && tans != tn) 
+      error(_("'na' is of type %s but '%s' is %s. Please make all arguments have the same type."), type2char(tn0), tans==ta0 ? "yes" : "no", tans==ta0 ? type2char(ta0) : type2char(tb0));
   }
-
-  if (!R_compute_identical(PROTECT(getAttrib(a,R_ClassSymbol)), PROTECT(getAttrib(b,R_ClassSymbol)), 0))
-    error(_("'yes' has different class than 'no'. Please make sure that both arguments have the same class."));
-  UNPROTECT(2);
-
-  if (isFactor(a)) {
-    if (!R_compute_identical(PROTECT(getAttrib(a,R_LevelsSymbol)), PROTECT(getAttrib(b,R_LevelsSymbol)), 0))
-      error(_("'yes' and 'no' are both type factor but their levels are different."));
+
+  if (!na_a && !na_b) {
+    if (!R_compute_identical(PROTECT(getAttrib(a,R_ClassSymbol)), PROTECT(getAttrib(b,R_ClassSymbol)), 0))
+      error(_("'yes' has different class than 'no'. Please make sure that both arguments have the same class."));
+    UNPROTECT(2);
+  }
+  if (!na_a && !na_n) {
+    if (!R_compute_identical(PROTECT(getAttrib(a,R_ClassSymbol)), PROTECT(getAttrib(na,R_ClassSymbol)), 0))
+      error(_("'yes' has different class than 'na'. Please make sure that both arguments have the same class."));
+    UNPROTECT(2);
+  }
+  if (!na_b && !na_n) {
+    if (!R_compute_identical(PROTECT(getAttrib(b,R_ClassSymbol)), PROTECT(getAttrib(na,R_ClassSymbol)), 0))
+      error(_("'no' has different class than 'na'. Please make sure that both arguments have the same class."));
     UNPROTECT(2);
   }
+
+  if (isFactor(a) || isFactor(b)) {
+    if (!na_a && !na_b) {
+      if (!R_compute_identical(PROTECT(getAttrib(a,R_LevelsSymbol)), PROTECT(getAttrib(b,R_LevelsSymbol)), 0))
+        error(_("'yes' and 'no' are both type factor but their levels are different."));
+      UNPROTECT(2);  
+    }
+    if (!na_a && !na_n) {
+      if (!R_compute_identical(PROTECT(getAttrib(a,R_LevelsSymbol)), PROTECT(getAttrib(na,R_LevelsSymbol)), 0))
+        error(_("'yes' and 'na' are both type factor but their levels are different."));
+      UNPROTECT(2);
+    }
+    if (!na_b && !na_n) {
+      if (!R_compute_identical(PROTECT(getAttrib(b,R_LevelsSymbol)), PROTECT(getAttrib(na,R_LevelsSymbol)), 0))
+        error(_("'no' and 'na' are both type factor but their levels are different."));
+      UNPROTECT(2);
+    }
+  }
 
-  if (len1!=1 && len1!=len0)
-    error(_("Length of 'yes' is %"PRId64" but must be 1 or length of 'test' (%"PRId64")."), len1, len0);
-  if (len2!=1 && len2!=len0)
-    error(_("Length of 'no' is %"PRId64" but must be 1 or length of 'test' (%"PRId64")."), len2, len0);
   const int64_t amask = len1>1 ? INT64_MAX : 0; // for scalar 'a' bitwise AND will reset iterator to first element: pa[i & amask] -> pa[0]
   const int64_t bmask = len2>1 ? INT64_MAX : 0;
+  const int64_t nmask = len3>1 ? INT64_MAX : 0;
 
   const int *restrict pl = LOGICAL(l);
-  SEXP ans = PROTECT(allocVector(ta, len0)); nprotect++;
-  copyMostAttrib(a, ans);
-
-  bool nonna = !isNull(na);
-  if (nonna) {
-    if (xlength(na) != 1)
-      error(_("Length of 'na' is %"PRId64" but must be 1"), (int64_t)xlength(na));
-    SEXPTYPE tn = TYPEOF(na);
-    if (tn == LGLSXP && LOGICAL(na)[0]==NA_LOGICAL) {
-      nonna = false;
-    } else {
-      if (tn != ta)
-        error(_("'yes' is of type %s but 'na' is of type %s. Please make sure that both arguments have the same type."), type2char(ta), type2char(tn));
-      if (!R_compute_identical(PROTECT(getAttrib(a,R_ClassSymbol)), PROTECT(getAttrib(na,R_ClassSymbol)), 0))
-        error(_("'yes' has different class than 'na'. Please make sure that both arguments have the same class."));
-      UNPROTECT(2);
-      if (isFactor(a)) {
-        if (!R_compute_identical(PROTECT(getAttrib(a,R_LevelsSymbol)), PROTECT(getAttrib(na,R_LevelsSymbol)), 0))
-          error(_("'yes' and 'na' are both type factor but their levels are different."));
-        UNPROTECT(2);
-      }
-    }
-  }
+  SEXP ans = PROTECT(allocVector(tans, len0)); nprotect++;
+  if (!na_a) 
+    copyMostAttrib(a, ans);
+  else if (!na_b)
+    copyMostAttrib(b, ans);
+  else if (!na_n)
+    copyMostAttrib(na, ans);
 
-  switch(ta) {
+  switch(tans) {
   case LGLSXP: {
     int *restrict pans = LOGICAL(ans);
-    const int *restrict pa   = LOGICAL(a);
-    const int *restrict pb   = LOGICAL(b);
-    const int pna = nonna ? LOGICAL(na)[0] : NA_LOGICAL;
+    const int *restrict pa;  if (!na_a) pa  = LOGICAL(a);
+    const int *restrict pb;  if (!na_b) pb  = LOGICAL(b);
+    const int *restrict pna; if (!na_n) pna = LOGICAL(na);
+    const int na = NA_LOGICAL;
     #pragma omp parallel for num_threads(getDTthreads(len0, true))
     for (int64_t i=0; i<len0; ++i) {
-      pans[i] = pl[i]==0 ? pb[i & bmask] : (pl[i]==1 ? pa[i & amask] : pna);
+      pans[i] = pl[i]==0 ?
+                (na_b ? na : pb[i & bmask]) :
+                pl[i]==1 ? 
+                (na_a ? na : pa[i & amask]) : 
+                (na_n ? na : pna[i & nmask]);
     }
   } break;
   case INTSXP: {
     int *restrict pans = INTEGER(ans);
-    const int *restrict pa   = INTEGER(a);
-    const int *restrict pb   = INTEGER(b);
-    const int pna = nonna ? INTEGER(na)[0] : NA_INTEGER;
+    const int *restrict pa;  if (!na_a) pa  = INTEGER(a);
+    const int *restrict pb;  if (!na_b) pb  = INTEGER(b);
+    const int *restrict pna; if (!na_n) pna = INTEGER(na);
+    const int na = NA_INTEGER;
     #pragma omp parallel for num_threads(getDTthreads(len0, true))
     for (int64_t i=0; i<len0; ++i) {
-      pans[i] = pl[i]==0 ? pb[i & bmask] : (pl[i]==1 ? pa[i & amask] : pna);
+      pans[i] = pl[i]==0 ?
+                (na_b ? na : pb[i & bmask]) :
+                pl[i]==1 ? 
+                (na_a ? na : pa[i & amask]) : 
+                (na_n ? na : pna[i & nmask]);
     }
   } break;
   case REALSXP: {
     double *restrict pans = REAL(ans);
-    const double *restrict pa   = REAL(a);
-    const double *restrict pb   = REAL(b);
-    const double na_double = Rinherits(a, char_integer64) ? NA_INT64_D : NA_REAL; // Rinherits() is true for nanotime
-    const double pna = nonna ? REAL(na)[0] : na_double;
+    const double *restrict pa;  if (!na_a) pa  = REAL(a);
+    const double *restrict pb;  if (!na_b) pb  = REAL(b);
+    const double *restrict pna; if (!na_n) pna = REAL(na);
+    const double na = Rinherits(a, char_integer64) ? NA_INT64_D : NA_REAL; // Rinherits() is true for nanotime
     #pragma omp parallel for num_threads(getDTthreads(len0, true))
     for (int64_t i=0; i<len0; ++i) {
-      pans[i] = pl[i]==0 ? pb[i & bmask] : (pl[i]==1 ? pa[i & amask] : pna);
+      pans[i] = pl[i]==0 ?
+                (na_b ? na : pb[i & bmask]) :
+                pl[i]==1 ? 
+                (na_a ? na : pa[i & amask]) : 
+                (na_n ? na : pna[i & nmask]);
     }
   } break;
   case STRSXP : {
-    const SEXP *restrict pa = STRING_PTR(a);
-    const SEXP *restrict pb = STRING_PTR(b);
-    const SEXP pna = nonna ? STRING_PTR(na)[0] : NA_STRING;
+    const SEXP *restrict pa;  if (!na_a) pa  = STRING_PTR(a);
+    const SEXP *restrict pb;  if (!na_b) pb  = STRING_PTR(b);
+    const SEXP *restrict pna; if (!na_n) pna = STRING_PTR(na);
+    const SEXP na = NA_STRING;
     for (int64_t i=0; i<len0; ++i) {
-      SET_STRING_ELT(ans, i, pl[i]==0 ? pb[i & bmask] : (pl[i]==1 ? pa[i & amask] : pna));
+      SET_STRING_ELT(
+        ans, i, pl[i]==0 ?
+                (na_b ? na : pb[i & bmask]) :
+                pl[i]==1 ? 
+                (na_a ? na : pa[i & amask]) : 
+                (na_n ? na : pna[i & nmask])
+      );
     }
   } break;
   case CPLXSXP : {
     Rcomplex *restrict pans = COMPLEX(ans);
-    const Rcomplex *restrict pa   = COMPLEX(a);
-    const Rcomplex *restrict pb   = COMPLEX(b);
-    const Rcomplex pna = nonna ? COMPLEX(na)[0] : NA_CPLX;
+    const Rcomplex *restrict pa;  if (!na_a) pa  = COMPLEX(a);
+    const Rcomplex *restrict pb;  if (!na_b) pb  = COMPLEX(b);
+    const Rcomplex *restrict pna; if (!na_n) pna = COMPLEX(na);
+    const Rcomplex na = NA_CPLX;
     #pragma omp parallel for num_threads(getDTthreads(len0, true))
     for (int64_t i=0; i<len0; ++i) {
-      pans[i] = pl[i]==0 ? pb[i & bmask] : (pl[i]==1 ? pa[i & amask] : pna);
+      pans[i] = pl[i]==0 ?
+                (na_b ? na : pb[i & bmask]) :
+                pl[i]==1 ? 
+                (na_a ? na : pa[i & amask]) : 
+                (na_n ? na : pna[i & nmask]);
     }
   } break;
   case VECSXP : {
-    const SEXP *restrict pa = SEXPPTR_RO(a);
-    const SEXP *restrict pb = SEXPPTR_RO(b);
-    const SEXP *restrict pna = SEXPPTR_RO(na);
+    const SEXP *restrict pa;  if (!na_a) pa  = SEXPPTR_RO(a);
+    const SEXP *restrict pb;  if (!na_b) pb  = SEXPPTR_RO(b);
+    const SEXP *restrict pna; if (!na_n) pna = SEXPPTR_RO(na);
     for (int64_t i=0; i<len0; ++i) {
-      if (pl[i]==NA_LOGICAL) {
-        if (nonna)
-          SET_VECTOR_ELT(ans, i, pna[0]);
-        continue; // allocVector already initialized with R_NilValue
+      if (pl[i] == NA_LOGICAL) {
+        if (!na_n) SET_VECTOR_ELT(ans, i, pna[i & nmask]);
+      } else if (pl[i]==0) {
+        if (!na_b) SET_VECTOR_ELT(ans, i, pb[i & bmask]);
+      } else if (pl[i]==1) {
+        if (!na_a) SET_VECTOR_ELT(ans, i, pa[i & amask]);
       }
-      SET_VECTOR_ELT(ans, i, pl[i]==0 ? pb[i & bmask] : pa[i & amask]);
     }
   } break;
   default: