From: Sam Moore <matches@ucc.asn.au>
Date: Mon, 21 Apr 2014 08:47:20 +0000 (+0800)
Subject: Ability to define Real as long double
X-Git-Url: https://git.ucc.asn.au/?p=ipdf%2Fcode.git;a=commitdiff_plain;h=c9ce50e17952b0feeec68758444a50302a0aafba;ds=inline

Ability to define Real as long double

`make DEF=-DREAL=2` to compile using long double as Real

Also changed calculatepi to include long double.
And also, only actually integrate using Real if it is something other than float, double, long double.
---

diff --git a/src/main.cpp b/src/main.cpp
index d9f2a7f..9b33453 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2,7 +2,12 @@
 #include <unistd.h> // Because we can.
 int main(int argc, char ** argv)
 {	
-	Debug("Compiled with REAL = %d => \"%s\"", REAL, g_real_name[REAL]);
+	#ifndef __STDC_IEC_559__
+       	Warn("__STDC_IEC_559__ not defined. IEEE 754 floating point not fully supported.\n");
+	#endif
+
+
+	Debug("Compiled with REAL = %d => \"%s\" sizeof(Real) == %d bytes", REAL, g_real_name[REAL], sizeof(Real));
 
 	Document doc;
 	srand(time(NULL));
diff --git a/src/real.cpp b/src/real.cpp
index 74c774b..7c70a92 100644
--- a/src/real.cpp
+++ b/src/real.cpp
@@ -5,7 +5,8 @@ namespace IPDF
 	// Maps the REAL to a string
 	const char * g_real_name[] = {
 		"single",
-		"double"
+		"double",
+		"long double"
 	};
 
 }
diff --git a/src/real.h b/src/real.h
index e6e69bc..0068472 100644
--- a/src/real.h
+++ b/src/real.h
@@ -5,6 +5,7 @@
 
 #define REAL_SINGLE 0
 #define REAL_DOUBLE 1
+#define REAL_LONG_DOUBLE 2
 
 #ifndef REAL
 	#error "REAL was not defined!"
@@ -20,6 +21,9 @@ namespace IPDF
 #elif REAL == REAL_DOUBLE
 	typedef double Real;
 	inline double Float(Real r) {return r;}
+#elif REAL == REAL_LONG_DOUBLE
+	typedef long double Real;
+	inline long double Float(Real r) {return r;}
 #else
 	#error "Type of Real unspecified."
 #endif //REAL
diff --git a/src/tests/calculatepi.cpp b/src/tests/calculatepi.cpp
index 46348ff..0b7692b 100644
--- a/src/tests/calculatepi.cpp
+++ b/src/tests/calculatepi.cpp
@@ -4,7 +4,7 @@
  * Compares results obtained with float, double, and Real.
  */
 #include "main.h"
-#include <cmath> // for PI
+#include <cmath>
 #include <ctime> // for performance measurements
 
 /** Function to integrate
@@ -19,7 +19,7 @@ template <class T> T f(const T & x)
 /**
  * Integrate f using the simpson rule
  */
-template <class T> T Integrate(T(*f)(const T&), const T & xmin, const T & xmax, uint64_t intervals)
+template <class T> T Integrate(T(*f)(const T & ), const T & xmin, const T & xmax, uint64_t intervals)
 {
 	T sum = 0.0;
 	T dx = (xmax - xmin) / T(intervals);
@@ -31,33 +31,47 @@ template <class T> T Integrate(T(*f)(const T&), const T & xmin, const T & xmax,
 		odd += f(xmin + dx*T(i));
 	for (i = 2; i < intervals-1; i+=2)
 		even += f(xmin + dx*T(i));
-
 	sum = (f(xmin) + T(4.0)*odd + T(2.0)*even + f(xmin+T(intervals)*dx))*dx / T(3.0);
 	return sum;
 
 }
 
-#define MAX_INTERVALS 1e9
-
+#define MAX_INTERVALS 1e10
 /**
  * main
  */
 int main(int argc, char ** argv)
 {
-	printf("# intervals\terror_float\tclock_float\terror_double\tclock_double\terror_real\tclock_real\n");
-	for (uint64_t intervals = 1; intervals < (uint64_t)(MAX_INTERVALS); intervals*=10)
+	setbuf(stdout, NULL);
+	setbuf(stderr, NULL);
+	long double PI = acosl(-1.0L);
+	printf("# intervals\terror_float\tclock_float\terror_double\tclock_double\terror_long\tclock_long");
+	#if REAL > REAL_LONG_DOUBLE
+		printf("\terror_real\tclock_real\n");
+	#else
+		printf("\n");
+	#endif //REAL
+	for (uint64_t intervals = 1; intervals < (uint64_t)(MAX_INTERVALS); intervals*=5)
 	{
 		clock_t start = clock();
-		float error_float = Integrate<float>(f<float>, 0.0, 1.0, intervals) - (float)(M_PI);
+		float error_float = Integrate<float>(f<float>, 0.0f, 1.0f, intervals) - float(PI);
 		clock_t clock_float = clock() - start;
 		start = clock();
-		double error_double = Integrate<double>(f<double>, 0.0, 1.0, intervals) - (double)(M_PI);
+		double error_double = Integrate<double>(f<double>, 0.0, 1.0, intervals) - double(PI);
 		clock_t clock_double = clock() - start;
 		start = clock();
-		Real error_real = Integrate<Real>(f<Real>, 0.0, 1.0, intervals) - Real(M_PI);
-		clock_t clock_real = clock() - start;
-	
-		printf("%lu\t%.30f\t%li\t%.30f\t%li\t%.30f\t%li\n", intervals, error_float, clock_float, error_double, clock_double, Float(error_real), clock_real);
+		long double error_long = Integrate<long double>(f<long double>,0.0L,1.0L, intervals) - PI;
+		clock_t clock_long = clock() - start;
+
+		printf("%lu\t%.30f\t%li\t%.30lf\t%li\t%.30llf\t%li", intervals, error_float, clock_float, error_double, clock_double, error_long, clock_long);
+		
+		#if REAL > REAL_LONG_DOUBLE
+			Real error_real = Integrate<Real>(f<Real>,Real(0.0L), Real(1.0L), intervals) - Real(PI);
+			clock_t clock_real = clock() - start;	
+			printf("\t%.30lf\t%li\n", error_real, clock_real);
+		#else
+			printf("\n");
+		#endif
 	}
 }