added GlobalStandardNormalizer class. changed names in StandardNormalizer class.

git-archimport-id: [email protected]/torch--devel--1.0--patch-71

Author: Ronan Collobert

datasets/T4GlobalStandardNormalizer.h

@@ -0,0 +1,21 @@
+#import "T4Object.h"
+#import "T4Matrix.h"
+
+@interface T4GlobalStandardNormalizer : T4Object <NSCoding>
+{
+    real mean;
+    real standardDeviation;
+}
+
+-initWithMean: (real)aMean standardDeviation: (real)aStandardDeviation;
+-initWithDataset: (NSArray*)aDataset columnIndex: (int)anIndex;
+-initWithDataset: (NSArray*)aDataset;
+
+-normalizeDataset: (NSArray*)aDataset columnIndex: (int)anIndex;
+-normalizeDataset: (NSArray*)aDataset;
+-normalizeMatrix: (T4Matrix*)aMatrix;
+
+-(real)mean;
+-(real)standardDeviation;
+
+@end

datasets/T4GlobalStandardNormalizer.m

@@ -0,0 +1,127 @@
+#import "T4GlobalStandardNormalizer.h"
+
+@implementation T4GlobalStandardNormalizer
+
+-initWithMean: (real)aMean standardDeviation: (real)aStandardDeviation
+{
+  if( (self = [super init]) )
+  {
+    mean = aMean;
+    standardDeviation = aStandardDeviation;
+  }
+
+  return self;
+}
+
+-initWithDataset: (NSArray*)aDataset columnIndex: (int)anIndex
+{  
+  int numRows;
+  int numExamples;
+  int numTotal;
+  real aMean;
+  real aStandardDeviation;
+  int r, c, e;
+
+  numExamples = [aDataset count];
+  numRows = [[[aDataset objectAtIndex: 0] objectAtIndex: anIndex] numberOfRows];
+
+  aMean = 0;
+  aStandardDeviation = 0;
+  numTotal = 0;
+
+  for(e = 0; e < numExamples; e++)
+  {
+    T4Matrix *matrix = [[aDataset objectAtIndex: e] objectAtIndex: anIndex];
+    int numColumns = [matrix numberOfColumns];
+
+    for(c = 0; c < numColumns; c++)
+    {
+      real *matrixColumn = [matrix columnAtIndex: c];
+      for(r = 0; r < numRows; r++)
+      {
+        real z = matrixColumn[r];
+        aMean += z;
+        aStandardDeviation += z*z;        
+      }
+    }
+
+    numTotal += numRows*numColumns;
+  }
+
+  aMean /= (real)numTotal;
+  aStandardDeviation /= (real)numTotal;
+  aStandardDeviation -= aMean*aMean;
+  aStandardDeviation = sqrt(aStandardDeviation);
+
+  return [self initWithMean: aMean standardDeviation: aStandardDeviation];
+}
+
+-initWithDataset: (NSArray*)aDataset
+{
+  return [self initWithDataset: aDataset columnIndex: 0];
+}
+
+-normalizeDataset: (NSArray*)aDataset columnIndex: (int)anIndex
+{
+  int numExamples = [aDataset count];
+  int e;
+
+  for(e = 0; e < numExamples; e++)
+  {
+    T4Matrix *matrix = [[aDataset objectAtIndex: e] objectAtIndex: anIndex];
+    [self normalizeMatrix: matrix];
+  }
+  return self;
+}
+
+-normalizeDataset: (NSArray*)aDataset
+{
+  return [self normalizeDataset: aDataset columnIndex: 0];
+}
+
+-normalizeMatrix: (T4Matrix*)aMatrix
+{
+  int numColumns = [aMatrix numberOfColumns];
+  int numRows = [aMatrix numberOfRows];
+  int r, c;
+
+  for(c = 0; c < numColumns; c++)
+  {
+    real *matrixColumn = [aMatrix columnAtIndex: c];
+    for(r = 0; r < numRows; r++)
+    {
+      if(standardDeviation > 0)
+        matrixColumn[r] = (matrixColumn[r] - mean) / standardDeviation;
+      else
+        matrixColumn[r] -= mean;
+    }
+  }
+  return self;
+}
+
+-(real)mean
+{
+  return mean;
+}
+
+-(real)standardDeviation
+{
+  return standardDeviation;
+}
+
+-initWithCoder: (NSCoder*)aCoder
+{
+  self = [super initWithCoder: aCoder];
+  [aCoder decodeValueOfObjCType: @encode(real) at: &mean];
+  [aCoder decodeValueOfObjCType: @encode(real) at: &standardDeviation];
+  return self;
+}
+
+-(void)encodeWithCoder: (NSCoder*)aCoder
+{
+  [super encodeWithCoder: aCoder];
+  [aCoder encodeValueOfObjCType: @encode(real) at: &mean];
+  [aCoder encodeValueOfObjCType: @encode(real) at: &standardDeviation];
+}
+
+@end

datasets/T4StandardNormalizer.h

@@ -3,19 +3,19 @@
 
 @interface T4StandardNormalizer : T4Object <NSCoding>
 {
-    T4Matrix *mean;
-    T4Matrix *standardDeviation;
+    T4Matrix *means;
+    T4Matrix *standardDeviations;
 }
 
--initWithMean: (T4Matrix*)aMean standardDeviation: (T4Matrix*)aStandardDeviation;
+-initWithMeans: (T4Matrix*)someMeans standardDeviations: (T4Matrix*)someStandardDeviations;
 -initWithDataset: (NSArray*)aDataset columnIndex: (int)anIndex;
 -initWithDataset: (NSArray*)aDataset;
 
 -normalizeDataset: (NSArray*)aDataset columnIndex: (int)anIndex;
 -normalizeDataset: (NSArray*)aDataset;
 -normalizeMatrix: (T4Matrix*)aMatrix;
 
--(T4Matrix*)mean;
--(T4Matrix*)standardDeviation;
+-(T4Matrix*)means;
+-(T4Matrix*)standardDeviations;
 
 @end

datasets/T4StandardNormalizer.m

@@ -2,15 +2,15 @@
 
 @implementation T4StandardNormalizer
 
--initWithMean: (T4Matrix*)aMean standardDeviation: (T4Matrix*)aStandardDeviation
+-initWithMeans: (T4Matrix*)someMeans standardDeviations: (T4Matrix*)someStandardDeviations
 {
   if( (self = [super init]) )
   {
-    if([aMean numberOfRows] != [aStandardDeviation numberOfRows])
+    if([someMeans numberOfRows] != [someStandardDeviations numberOfRows])
       T4Error(@"StandardNormalizer: mean and standard deviation matrices do not match!!!");
 
-    mean = [aMean retainAndKeepWithAllocator: allocator];
-    standardDeviation = [aStandardDeviation retainAndKeepWithAllocator: allocator];
+    means = [someMeans retainAndKeepWithAllocator: allocator];
+    standardDeviations = [someStandardDeviations retainAndKeepWithAllocator: allocator];
   }
 
   return self;
@@ -21,20 +21,20 @@ @implementation T4StandardNormalizer
   int numRows;
   int numExamples;
   int totalNumColumns;
-  T4Matrix *aMean;
-  T4Matrix *aStandardDeviation;
+  T4Matrix *someMeans;
+  T4Matrix *someStandardDeviations;
   real *meanColumn;
   real *standardDeviationColumn;
   int r, c, e;
 
   numExamples = [aDataset count];
   numRows = [[[aDataset objectAtIndex: 0] objectAtIndex: anIndex] numberOfRows];
-  aMean = [[[T4Matrix alloc] initWithNumberOfRows: numRows] keepWithAllocator: allocator];
-  aStandardDeviation = [[[T4Matrix alloc] initWithNumberOfRows: numRows] keepWithAllocator: allocator];
-  meanColumn = [aMean firstColumn];
-  standardDeviationColumn = [aStandardDeviation firstColumn];
-  [aMean zero];
-  [aStandardDeviation zero];
+  someMeans = [[[T4Matrix alloc] initWithNumberOfRows: numRows] keepWithAllocator: allocator];
+  someStandardDeviations = [[[T4Matrix alloc] initWithNumberOfRows: numRows] keepWithAllocator: allocator];
+  meanColumn = [someMeans firstColumn];
+  standardDeviationColumn = [someStandardDeviations firstColumn];
+  [someMeans zero];
+  [someStandardDeviations zero];
   totalNumColumns = 0;
 
   for(e = 0; e < numExamples; e++)
@@ -64,7 +64,7 @@ @implementation T4StandardNormalizer
     standardDeviationColumn[r] = sqrt(standardDeviationColumn[r]);
   }
 
-  return [self initWithMean: aMean standardDeviation: aStandardDeviation];
+  return [self initWithMeans: someMeans standardDeviations: someStandardDeviations];
 }
 
 -initWithDataset: (NSArray*)aDataset
@@ -94,8 +94,8 @@ @implementation T4StandardNormalizer
 {
   int numColumns = [aMatrix numberOfColumns];
   int numRows = [aMatrix numberOfRows];
-  real *meanColumn = [mean firstColumn];
-  real *standardDeviationColumn = [standardDeviation firstColumn];
+  real *meanColumn = [means firstColumn];
+  real *standardDeviationColumn = [standardDeviations firstColumn];
   int r, c;
 
   for(c = 0; c < numColumns; c++)
@@ -112,29 +112,29 @@ @implementation T4StandardNormalizer
   return self;
 }
 
--(T4Matrix*)mean
+-(T4Matrix*)means
 {
-  return mean;
+  return means;
 }
 
--(T4Matrix*)standardDeviation
+-(T4Matrix*)standardDeviations
 {
-  return standardDeviation;
+  return standardDeviations;
 }
 
 -initWithCoder: (NSCoder*)aCoder
 {
   self = [super initWithCoder: aCoder];
-  mean = [[aCoder decodeObject] retainAndKeepWithAllocator: allocator];
-  standardDeviation = [[aCoder decodeObject] retainAndKeepWithAllocator: allocator];
+  means = [[aCoder decodeObject] retainAndKeepWithAllocator: allocator];
+  standardDeviations = [[aCoder decodeObject] retainAndKeepWithAllocator: allocator];
   return self;
 }
 
 -(void)encodeWithCoder: (NSCoder*)aCoder
 {
   [super encodeWithCoder: aCoder];
-  [aCoder encodeObject: mean];
-  [aCoder encodeObject: standardDeviation];
+  [aCoder encodeObject: means];
+  [aCoder encodeObject: standardDeviations];
 }
 
 @end