support nan and inf in parser.

include/LightGBM/utils/common.h

@@ -80,6 +80,7 @@ inline static const char* Atoi(const char* p, int* out) {
 inline static const char* Atof(const char* p, double* out) {
   int frac;
   double sign, value, scale;
+
   // Skip leading white space, if any.
   while (*p == ' ') {
     ++p;
@@ -95,51 +96,85 @@ inline static const char* Atof(const char* p, double* out) {
     ++p;
   }
 
-  // Get digits before decimal point or exponent, if any.
-  for (value = 0.0; *p >= '0' && *p <= '9'; ++p) {
-    value = value * 10.0 + (*p - '0');
-  }
+  // is a number
+  if ((*p >= '0' && *p <= '9') || *p == '.' || *p == 'e' || *p == 'E') {
+    // Get digits before decimal point or exponent, if any.
+    for (value = 0.0; *p >= '0' && *p <= '9'; ++p) {
+      value = value * 10.0 + (*p - '0');
+    }
 
-  // Get digits after decimal point, if any.
-  if (*p == '.') {
-    double pow10 = 10.0;
-    ++p;
-    while (*p >= '0' && *p <= '9') {
-      value += (*p - '0') / pow10;
-      pow10 *= 10.0;
+    // Get digits after decimal point, if any.
+    if (*p == '.') {
+      double pow10 = 10.0;
       ++p;
+      while (*p >= '0' && *p <= '9') {
+        value += (*p - '0') / pow10;
+        pow10 *= 10.0;
+        ++p;
+      }
     }
-  }
 
-  // Handle exponent, if any.
-  frac = 0;
-  scale = 1.0;
-  if ((*p == 'e') || (*p == 'E')) {
-    unsigned int expon;
-    // Get sign of exponent, if any.
-    ++p;
-    if (*p == '-') {
-      frac = 1;
+    // Handle exponent, if any.
+    frac = 0;
+    scale = 1.0;
+    if ((*p == 'e') || (*p == 'E')) {
+      unsigned int expon;
+      // Get sign of exponent, if any.
       ++p;
+      if (*p == '-') {
+        frac = 1;
+        ++p;
+      } else if (*p == '+') {
+        ++p;
+      }
+      // Get digits of exponent, if any.
+      for (expon = 0; *p >= '0' && *p <= '9'; ++p) {
+        expon = expon * 10 + (*p - '0');
+      }
+      if (expon > 308) expon = 308;
+      // Calculate scaling factor.
+      while (expon >= 50) { scale *= 1E50; expon -= 50; }
+      while (expon >= 8) { scale *= 1E8;  expon -= 8; }
+      while (expon > 0) { scale *= 10.0; expon -= 1; }
     }
-    else if (*p == '+') {
+    // Return signed and scaled floating point result.
+    *out = sign * (frac ? (value / scale) : (value * scale));
+  } else {
+    if (*p == 'n' || *p == 'N') {
       ++p;
+      if (!(*p == 'a' || *p == 'A')) {
+        Log::Stderr("meet error while parsing string to float, expect a nan here");
+      }
+      ++p;
+      if (!(*p == 'n' || *p == 'N')) {
+        Log::Stderr("meet error while parsing string to float, expect a nan here");
+      }
+      ++p;
+      // default convert nan to 0
+      *out = 0;
+    } else if (*p == 'i' || *p == 'I') {
+      ++p;
+      if (!(*p == 'n' || *p == 'N')) {
+        Log::Stderr("meet error while parsing string to float, expect a inf here");
+      }
+      ++p;
+      if (!(*p == 'f' || *p == 'F')) {
+        Log::Stderr("meet error while parsing string to float, expect a inf here");
+      }
+      ++p;
+      // default inf
+      *out = sign * 1e308;
+    } else {
+      if (*p != '\0') {
+        Log::Stderr("Meet unknow characters while parsing string to float");
+      }
     }
-    // Get digits of exponent, if any.
-    for (expon = 0; *p >= '0' && *p <= '9'; ++p) {
-      expon = expon * 10 + (*p - '0');
-    }
-    if (expon > 308) expon = 308;
-    // Calculate scaling factor.
-    while (expon >= 50) { scale *= 1E50; expon -= 50; }
-    while (expon >= 8) { scale *= 1E8;  expon -= 8; }
-    while (expon > 0) { scale *= 10.0; expon -= 1; }
   }
-  // Return signed and scaled floating point result.
-  *out = sign * (frac ? (value / scale) : (value * scale));
+
   while (*p == ' ') {
     ++p;
   }
+
   return p;
 }
 

src/io/parser.cpp

@@ -5,7 +5,7 @@
 
 namespace LightGBM {
 
-void GetStatistic(const char* str, int* comma_cnt, int* tab_cnt, int *colon_cnt) {
+void GetStatistic(const char* str, int* comma_cnt, int* tab_cnt, int* colon_cnt) {
   *comma_cnt = 0;
   *tab_cnt = 0;
   *colon_cnt = 0;

src/io/parser.hpp

@@ -15,7 +15,7 @@ namespace LightGBM {
 class CSVParser: public Parser {
 public:
   inline void ParseOneLine(const char* str,
-                           std::vector<std::pair<int, double>>* out_features) const override {
+    std::vector<std::pair<int, double>>* out_features) const override {
     int idx = 0;
     double val = 0.0;
     while (*str != '\0') {
@@ -30,16 +30,14 @@ public:
     }
   }
   inline void ParseOneLine(const char* str, std::vector<std::pair<int, double>>* out_features,
-                                                           double* out_label) const override {
+    double* out_label) const override {
     // first column is label
     str = Common::Atof(str, out_label);
-
-	if (*str == ',') {
-		++str;
-	} else if (*str != '\0') {
-		Log::Stderr("input format error, should be CSV");
-	}
-
+    if (*str == ',') {
+      ++str;
+    } else if (*str != '\0') {
+      Log::Stderr("input format error, should be CSV");
+    }
     return ParseOneLine(str, out_features);
   }
 };
@@ -61,16 +59,14 @@ public:
     }
   }
   inline void ParseOneLine(const char* str, std::vector<std::pair<int, double>>* out_features,
-                                                           double* out_label) const override{
+    double* out_label) const override {
     // first column is label
     str = Common::Atof(str, out_label);
-
-	if (*str == '\t') {
-		++str;
-	} else if (*str != '\0') {
-		Log::Stderr("input format error, should be TSV");
-	}
-
+    if (*str == '\t') {
+      ++str;
+    } else if (*str != '\0') {
+      Log::Stderr("input format error, should be TSV");
+    }
     return ParseOneLine(str, out_features);
   }
 };
@@ -94,7 +90,7 @@ public:
     }
   }
   inline void ParseOneLine(const char* str, std::vector<std::pair<int, double>>* out_features,
-                                                            double* out_label) const override{
+    double* out_label) const override {
     // first column is label
     str = Common::Atof(str, out_label);
     str = Common::SkipSpaceAndTab(str);