Add extra options to CreateFrame to make (potentially sparse) binary …

…columns.

src/main/java/hex/CreateFrame.java

@@ -41,6 +41,12 @@ public class CreateFrame extends Request2 {
   @API(help = "Fraction of categorical columns (for randomize=true)", filter = Default.class, dmin = 0, dmax = 1, json=true)
   public double categorical_fraction = 0.2;
 
+  @API(help = "Fraction of binary columns (for randomize=true)", filter = Default.class, dmin = 0, dmax = 1, json=true)
+  public double binary_fraction = 0.1;
+
+  @API(help = "Approximate fraction of 1's in binary columns", filter = Default.class, dmin = 0, dmax = 1, json=true)
+  public double binary_ones_fraction = 0.02;
+
   @API(help = "Factor levels for categorical variables", filter = Default.class, lmin = 2, json=true)
   public int factors = 100;
 
@@ -60,9 +66,11 @@ public class CreateFrame extends Request2 {
 
   @Override public Response serve() {
     try {
-      if (integer_fraction + categorical_fraction > 1) throw new IllegalArgumentException("Integer and categorical fractions must add up to <= 1.");
+      if (integer_fraction + binary_fraction + categorical_fraction > 1) throw new IllegalArgumentException("Integer, binary and categorical fractions must add up to <= 1.");
       if (Math.abs(missing_fraction) > 1) throw new IllegalArgumentException("Missing fraction must be between 0 and 1.");
       if (Math.abs(integer_fraction) > 1) throw new IllegalArgumentException("Integer fraction must be between 0 and 1.");
+      if (Math.abs(binary_fraction) > 1) throw new IllegalArgumentException("Binary fraction must be between 0 and 1.");
+      if (Math.abs(binary_ones_fraction) > 1) throw new IllegalArgumentException("Binary ones fraction must be between 0 and 1.");
       if (Math.abs(categorical_fraction) > 1) throw new IllegalArgumentException("Categorical fraction must be between 0 and 1.");
       if (categorical_fraction > 0 && factors <= 1) throw new IllegalArgumentException("Factors must be larger than 2 for categorical data.");
       if (response_factors < 1) throw new IllegalArgumentException("Response factors must be either 1 (real-valued response), or >=2 (factor levels).");

src/main/java/water/fvec/FrameCreator.java

@@ -29,15 +29,18 @@ public FrameCreator(CreateFrame createFrame, Key job) {
 
     int catcols = (int)(_createFrame.categorical_fraction * _createFrame.cols);
     int intcols = (int)(_createFrame.integer_fraction * _createFrame.cols);
-    int realcols = _createFrame.cols - catcols - intcols;
+    int bincols = (int)(_createFrame.binary_fraction * _createFrame.cols);
+    int realcols = _createFrame.cols - catcols - intcols - bincols;
 
     assert(catcols >= 0);
     assert(intcols >= 0);
+    assert(bincols >= 0);
     assert(realcols >= 0);
 
-    _cat_cols  = Arrays.copyOfRange(shuffled_idx, 0,               catcols);
-    _int_cols  = Arrays.copyOfRange(shuffled_idx, catcols,         catcols+intcols);
-    _real_cols = Arrays.copyOfRange(shuffled_idx, catcols+intcols, catcols+intcols+realcols);
+    _cat_cols  = Arrays.copyOfRange(shuffled_idx, 0,                        catcols);
+    _int_cols  = Arrays.copyOfRange(shuffled_idx, catcols,                  catcols+intcols);
+    _real_cols = Arrays.copyOfRange(shuffled_idx, catcols+intcols,          catcols+intcols+realcols);
+    _bin_cols  = Arrays.copyOfRange(shuffled_idx, catcols+intcols+realcols, catcols+intcols+realcols+bincols);
 
     // create domains for categorical variables
     if (_createFrame.randomize) {
@@ -63,6 +66,7 @@ public FrameCreator(CreateFrame createFrame, Key job) {
   private int[] _cat_cols;
   private int[] _int_cols;
   private int[] _real_cols;
+  private int[] _bin_cols;
   private String[][] _domain;
   private Frame _out;
   final private Key _job;
@@ -79,7 +83,7 @@ public FrameCreator(CreateFrame createFrame, Key job) {
     _out.delete_and_lock(_job);
 
     // fill with random values
-    new FrameRandomizer(_createFrame, _cat_cols, _int_cols, _real_cols).doAll(_out);
+    new FrameRandomizer(_createFrame, _cat_cols, _int_cols, _real_cols, _bin_cols).doAll(_out);
 
     //overwrite a fraction with N/A
     new MissingInserter(this, _createFrame.seed, _createFrame.missing_fraction).asyncExec(_out);
@@ -95,12 +99,14 @@ private static class FrameRandomizer extends MRTask2<FrameRandomizer> {
     final private int[] _cat_cols;
     final private int[] _int_cols;
     final private int[] _real_cols;
+    final private int[] _bin_cols;
 
-    public FrameRandomizer(CreateFrame createFrame, int[] cat_cols, int[] int_cols, int[] real_cols){
+    public FrameRandomizer(CreateFrame createFrame, int[] cat_cols, int[] int_cols, int[] real_cols, int[] bin_cols){
       _createFrame = createFrame;
       _cat_cols = cat_cols;
       _int_cols = int_cols;
       _real_cols = real_cols;
+      _bin_cols = bin_cols;
     }
 
     //row+col-dependent RNG for reproducibility with different number of VMs, chunks, etc.
@@ -143,6 +149,12 @@ else if (_createFrame.positive_response)
           cs[c].set0(r, _createFrame.real_range * (1 - 2 * rng.nextDouble()));
         }
       }
+      for (int c : _bin_cols) {
+        for (int r = 0; r < cs[c]._len; r++) {
+          setSeed(rng, c, cs[c]._start + r);
+          cs[c].set0(r, rng.nextFloat() > _createFrame.binary_ones_fraction ? 0 : 1);
+        }
+      }
     }
   }