Merge pull request #56 from albrow/master

Use a user-configurable log.Logger to print to console instead of fmt.Println

base/logger.go

@@ -0,0 +1,34 @@
+package base
+
+import (
+	"io"
+	"log"
+	"os"
+)
+
+// Logger is the default logger for the entire golearn package. It writes
+// to stdout and has no prefix and no flags.
+var Logger *log.Logger = log.New(os.Stdout, "", 0)
+
+// SetLogger sets the base logger for the entire golearn package.
+func SetLogger(logger *log.Logger) {
+	Logger = logger
+}
+
+// SetLoggerOut creates a new base logger for the entire golearn
+// package using the given out instead of the default, os.Stdout.
+// The other log options are set to the default, i.e. no prefix and no
+// flags.
+func SetLoggerOut(out io.Writer) {
+	Logger = log.New(out, "", 0)
+}
+
+// Silent turns off logging throughout the golearn package by setting
+// the logger to write to dev/null.
+func Silent() {
+	if out, err := os.Open(os.DevNull); err != nil {
+		panic(err)
+	} else {
+		Logger = log.New(out, "", 0)
+	}
+}

linear_models/cfuncs.go

@@ -0,0 +1,14 @@
+// +build go1.2
+
+package linear_models
+
+/*
+
+void libLinearPrintFunc(char *);
+
+void golearn_liblinear_print_func_cgo(char *c) {
+    libLinearPrintFunc(c);
+}
+
+*/
+import "C"

linear_models/liblinear.go

@@ -59,6 +59,7 @@ func NewProblem(X [][]float64, y []float64, bias float64) *Problem {
 }
 
 func Train(prob *Problem, param *Parameter) *Model {
+	libLinearHookPrintFunc() // Sets up logging
 	return &Model{C.train(&prob.c_prob, &param.c_param)}
 }
 

linear_models/liblinear_print.go

@@ -0,0 +1,27 @@
+// +build go1.2
+
+package linear_models
+
+/*
+#cgo LDFLAGS: -llinear
+#cgo CFLAGS:
+#include <linear.h>
+
+typedef void (*print_func)(char *);
+void golearn_liblinear_print_func_cgo(char *);
+*/
+import "C"
+
+import (
+	"github.com/sjwhitworth/golearn/base"
+	"unsafe"
+)
+
+//export libLinearPrintFunc
+func libLinearPrintFunc(str *C.char) {
+	base.Logger.Println(C.GoString(str))
+}
+
+func libLinearHookPrintFunc() {
+	C.set_print_string_function((C.print_func)(unsafe.Pointer(C.golearn_liblinear_print_func_cgo)))
+}

linear_models/liblinear_print_11.go

@@ -0,0 +1,16 @@
+// +build go1.1
+// +build !go1.2
+// +build !go1.3
+
+package linear_models
+
+import "C"
+
+//export libLinearPrintFunc
+func libLinearPrintFunc(str *C.char) {
+	// Stubbed
+}
+
+func libLinearHookPrintFunc() {
+	// Stubbed
+}

linear_models/logistic.go

@@ -40,7 +40,7 @@ func convertInstancesToProblemVec(X *base.Instances) [][]float64 {
 			problemVecCounter++
 		}
 	}
-	fmt.Println(problemVec, X)
+	base.Logger.Println(problemVec, X)
 	return problemVec
 }
 
@@ -70,7 +70,7 @@ func (lr *LogisticRegression) Predict(X *base.Instances) *base.Instances {
 				rowCounter++
 			}
 		}
-		fmt.Println(Predict(lr.model, row), row)
+		base.Logger.Println(Predict(lr.model, row), row)
 		ret.Set(i, 0, Predict(lr.model, row))
 	}
 	return ret

trees/random.go

@@ -25,7 +25,7 @@ func (r *RandomTreeRuleGenerator) GenerateSplitAttribute(f *base.Instances) base
 			break
 		}
 		selectedAttribute := rand.Intn(maximumAttribute)
-		fmt.Println(selectedAttribute, attrCounter, consideredAttributes, len(consideredAttributes))
+		base.Logger.Println(selectedAttribute, attrCounter, consideredAttributes, len(consideredAttributes))
 		if selectedAttribute != f.ClassIndex {
 			matched := false
 			for _, a := range consideredAttributes {