From ff76b2ab5126636ad509e6ba1e01ccc67b773467 Mon Sep 17 00:00:00 2001
From: Markus Blatt <mblatt@dune-project.org>
Date: Thu, 19 Nov 2009 10:22:25 +0000
Subject: [PATCH] Added conversion to double
[[Imported from SVN: r5714]]
---
dune/common/bigunsignedint.hh | 23 ++++++++++++++++++++-
dune/common/test/bigunsignedinttest.cc | 28 ++++++--------------------
2 files changed, 28 insertions(+), 23 deletions(-)
diff --git a/dune/common/bigunsignedint.hh b/dune/common/bigunsignedint.hh
index 845d88c12..53ba0e60f 100644
--- a/dune/common/bigunsignedint.hh
+++ b/dune/common/bigunsignedint.hh
@@ -124,6 +124,7 @@ namespace Dune
//! export to other types
// operator unsigned int () const;
unsigned int touint() const;
+ double todouble() const;
friend class bigunsignedint<k/2>;
friend class std::numeric_limits<bigunsignedint<k> >;
@@ -141,7 +142,9 @@ namespace Dune
// Constructors
template<int k>
bigunsignedint<k>::bigunsignedint ()
- { }
+ {
+ assign(0u);
+ }
template<int k>
bigunsignedint<k>::bigunsignedint (int y)
@@ -175,6 +178,24 @@ namespace Dune
return (digit[1]<<bits)+digit[0];
}
+ template<int k>
+ inline double bigunsignedint<k>::todouble() const
+ {
+ int firstInZeroRange=n;
+ for(int i=n-1; i>=0; --i)
+ if(digit[i]!=0)
+ break;
+ else
+ --firstInZeroRange;
+ int representableDigits=std::numeric_limits<double>::digits/bits;
+ int lastInRepresentableRange=0;
+ if(representableDigits<firstInZeroRange)
+ lastInRepresentableRange=firstInZeroRange-representableDigits;
+ double val=0;
+ for(int i=firstInZeroRange-1; i>=lastInRepresentableRange; --i)
+ val =val*(1<<bits)+digit[i];
+ return val*(1<<(bits*lastInRepresentableRange));
+ }
// print
template<int k>
inline void bigunsignedint<k>::print (std::ostream& s) const
diff --git a/dune/common/test/bigunsignedinttest.cc b/dune/common/test/bigunsignedinttest.cc
index 2586185cb..80e3451d4 100644
--- a/dune/common/test/bigunsignedinttest.cc
+++ b/dune/common/test/bigunsignedinttest.cc
@@ -47,25 +47,8 @@ int main()
Dune::bigunsignedint<100> a, b, c;
a=100;
- int ret=0;
- if(a.touint()!=100)
- {
- std::cerr<<"wrong conversion"<<std::endl;
- ++ret;
- }
-
b=3;
- if(b.touint()!=3)
- {
- std::cerr<<"wrong conversion"<<std::endl;
- ++ret;
- }
c=a/b;
- if(c.touint()!=100/3)
- {
- std::cerr<<"wrong conversion"<<std::endl;
- ++ret;
- }
std::cout<<a<<"/"<<b<<"="<<c<<std::endl;
try{
@@ -74,13 +57,14 @@ int main()
b=0;
c=a/1;
std::cout<<a1<<"/"<<b1<<"="<<c1<<std::endl;
- return ret;
-
+ a=1000000;
+ std::cout<<a.todouble()<<std::endl;
+ std::cout<<a.touint()<<std::endl;
+ b=a;
+ a=a*b*b;
+ std::cout<<a.todouble()<<std::endl;
}
catch(Dune::MathError e) {
std::cout<<e<<std::endl;
- return 1;
}
-
-
}
--
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