From 58dfc538adf7752d9038454292932354051fee99 Mon Sep 17 00:00:00 2001
From: Miles Stoudenmire <miles.stoudenmire@gmail.com>
Date: Thu, 24 Apr 2014 13:54:27 -0400
Subject: [PATCH] Added more convenient interface to InputGroup class which
 allows defining parameters on a single line and specifying defaults.

---
 sample/dmrg_table.cc | 13 ++++----
 utilities/input.cc   | 89 +++++++++++++++++++++++++++++++++++++++-------------
 utilities/input.h    | 13 ++++++++
 3 files changed, 87 insertions(+), 28 deletions(-)

diff --git a/sample/dmrg_table.cc b/sample/dmrg_table.cc
index b62eaa43..cc5c89b0 100644
--- a/sample/dmrg_table.cc
+++ b/sample/dmrg_table.cc
@@ -27,14 +27,15 @@ int main(int argc, char* argv[])
     InputGroup basic(infile,"basic");
 
     //Read in individual parameters from the input file
-    int N = 0;
-    basic.GetIntM("N",N); //the 'M' stands for mandatory
-    int nsweeps = 0;
-    basic.GetIntM("nsweeps",nsweeps);
-    int quiet = 1;
-    basic.GetYesNo("quiet",quiet);
+    const int N = basic.getInt("N");
+    const int nsweeps = basic.getInt("nsweeps");
+    //second argument to getXXX methods is a default
+    //in case parameter not provided in input file
+    const bool quiet = basic.getYesNo("quiet",true);
 
+    //
     // Read the sweeps parameters from a table.
+    //
 
     //Read in the sweeps table itself
     InputGroup table(basic,"sweeps");
diff --git a/utilities/input.cc b/utilities/input.cc
index d72534a2..217ba755 100644
--- a/utilities/input.cc
+++ b/utilities/input.cc
@@ -277,35 +277,44 @@ int InputGroup::GetYesNo(string s, int& yes,const char* c)
     {
     string res;
     if(!GotoToken(s) || !(infile.file >> res)) 
-	{
-	if(!quiet) 
-    {
-    cout << "Couldnt get " << name << "." << s;
-	if(c) cout  << ": " << c;
-	cout << endl;
-    }
-	return 0;
-	}
+        {
+        if(!quiet) 
+            {
+            cout << "Couldnt get " << name << "." << s;
+            if(c) cout  << ": " << c;
+            cout << endl;
+            }
+        return 0;
+        }
     if(!quiet) 
-    {
-    cout << "Got " << name << "." << s << " = " << res;
-    if(c) cout  << ": " << c;
-    cout << endl;
-    }
+        {
+        cout << "Got " << name << "." << s << " = " << res;
+        if(c) cout  << ": " << c;
+        cout << endl;
+        }
     transform(res.begin(),res.end(),res.begin(),mydolower);
     if(res == "yes" || res == "y")
-	{
-	yes = 1;
-	return 1;
-	}
+        {
+        yes = 1;
+        return 1;
+        }
     if(res == "no" || res == "n")
-	{
-	yes = 0;
-	return 1;
-	}
+        {
+        yes = 0;
+        return 1;
+        }
     return 0;
     }
 
+int InputGroup::
+GetYesNo(string s, bool& yes,const char* c)
+    {
+    int resi = 0;
+    int got = GetYesNo(s,resi,c);
+    yes = (resi==1);
+    return got;
+    }
+
 void InputGroup::SkipLine()
     {
     char c = '\0';
@@ -314,6 +323,42 @@ void InputGroup::SkipLine()
     eatwhite(infile.file);
     }
 
+int InputGroup::
+getInt(std::string s, int def, const char* c)
+    {
+    int res = 0;
+    int got = GetInt(s,res,c);
+    if(!got) return def;
+    return res;
+    }
+
+Real InputGroup::
+getReal(std::string s, Real def, const char* c)
+    {
+    Real res = 0;
+    int got = GetReal(s,res,c);
+    if(!got) return def;
+    return res;
+    }
+
+std::string  InputGroup::
+getString(std::string s, std::string def, const char* c)
+    {
+    std::string res;
+    int got = GetString(s,res,c);
+    if(!got) return def;
+    return res;
+    }
+
+bool  InputGroup::
+getYesNo(std::string s, bool def, const char* c)
+    {
+    bool res = false;
+    int got = GetYesNo(s,res,c);
+    if(!got) return def;
+    return res;
+    }
+
 void InputGroup::GetIntM(string s, int& res,const char* c)
     {
     if(!GetInt(s,res,c))
diff --git a/utilities/input.h b/utilities/input.h
index 431a373a..8298a042 100644
--- a/utilities/input.h
+++ b/utilities/input.h
@@ -13,10 +13,16 @@
 #include <string>
 //#include "String.h"
 #include <cctype>
+#include "math.h"
+#include <cmath>
 #define SP << " " <<
 typedef double Real;
 void error(const std::string& s);
 
+#ifndef NAN
+#define NAN (std::numeric_limits<Real>::quiet_NaN())
+#endif
+
 class InputFile
     {
 public:
@@ -63,6 +69,13 @@ class InputGroup
     int GetReal(std::string s, Real& r,const char* c = 0);	
     int GetString(std::string s, std::string& t,const char* c = 0);
     int GetYesNo(std::string s, int& yes,const char* c = 0);	 // understands yes/no
+    int GetYesNo(std::string s, bool& yes,const char* c = 0);	 // understands yes/no
+
+    //These versions return their value
+    int getInt(std::string s, int def = 0, const char* c = 0);
+    Real getReal(std::string s, Real def = NAN, const char* c = 0);
+    std::string getString(std::string s, std::string def = "", const char* c = 0);
+    bool getYesNo(std::string s, bool def = false, const char* c = 0);
 
 // The following are mandatory versions; if they doesn't get it, we quit
     void GetIntM(std::string s, int& i,const char* c = 0);