Boost library for numeric types with arbitrary precision.
This library allows to create numeric types with a greater precision than default types like double int and so on.
Questions tagged [boost-multiprecision]
59 questions
8
votes
1 answer
C2143/C2518 when trying to compile project using boost.multiprecision
I've been having problems trying to get boost.multiprecision to work in my VC2017 project, and I tried to make the simplest project possible as a proof of concept:
#include
int main() {
…
Xirema
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6
votes
1 answer
Why does Boost::multiprecision::sqrt(1) return 0?
Boost::multiprecision::sqrt(1) seems to return 0
#include
#include
#include
using std::cout;
using std::endl;
int main() {
namespace mp = boost::multiprecision;
…
Chad
- 548
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4
votes
1 answer
boost::multiprecision::uint128_t sizeof is 24
Basic math (128 / 8 = 16) speaks differently. I'm kinda disappointed and want some answers - since from what I've been used to, that notation(type_num_of_bytes_t) describes not just the amount of data you can put into the variable, but also…
Leontyev Georgiy
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3
votes
2 answers
C++ boost/multiprecision: fatal error: mpfr.h: No such file or directory
I have followed this answer and used Boost.Multiprecision to use high accuracy floating point numbers (examples).
main.cpp
#include
#include // Defines the Backend type that wraps MPFR
int main(int argc,…
ar2015
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3
votes
0 answers
boost::multiprecision::export_bits throws on a negative cpp_int number
When calling export_bits on a negative boost::multiprecision number based on cpp_int, an exception is thrown from the internal method msb ("testing individual bits in negative values is not supported"). (Boost…
ta55e
- 184
- 8
3
votes
1 answer
how to change at runtime number precision with boost::multiprecision
I've read from the boost::multiprecision documentation:
Depending upon the number type, precision may be arbitrarily large (limited only by available memory), fixed at compile time (for example 50 or 100 decimal digits), or a variable controlled at…
Jepessen
- 9,377
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2
votes
2 answers
boost::multiprecision random number with fixed seed and variable precision
When using a fixed seed inside a rng, results are not reproducible when precision is varied. Namely, if one changes the template argument cpp_dec_float and runs the following code, different outputs are seen (for each change in…
algae
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2
votes
1 answer
How to set rounding mode in Boost Multiprecision when using MPFR
I am trying to figure out how I can format mpfr_float numbers using a rounding mode in Boost Multiprecision. In the below example, I expect 1.55 to round to either 1.5 or 1.6 depending on which rounding mode is used, but instead for all cases it…
Jay
- 23
- 4
2
votes
2 answers
Type trait for boost multiprecision integers
I want to write a type trait to identify boost multiprecision integer types. I can do this for a concrete type like uint256_t:
template
struct is_multiprecision_int : std::false_type {};
template <>
struct…
Silicomancer
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2
votes
1 answer
Why does odeint fail with the newer versions of odeint?
I was struggling with the new version of boost. I am using odeint with mupltiprecision. The following piece of code can be successfully compiled with boost version 1.67.0. However, since version 1.68.0 and newer, I can no longer compile. In version…
Schnarco
- 173
- 4
2
votes
1 answer
Find First Set instruction (ffs) for boost multiprecision uint512_t
I'm developing an algorithm that uses __builtin_ffsll() with uint64_t type.
I want to switch to 512-bit field using boost multiprecision library (I'm running on a machine with avx512 support).
Is there a similar function as the mentioned builtin?…
Purple
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2
votes
1 answer
Mysterious stackoverflow exception in boost::multiprecision::gmp_float::operator=?
I am trying to calculate pi for one of my university project using Ramanujan's formula for arbitrary number of digits after the floating point. For the job, I am using boost::multiprecision library that is simply wrapper around mpfr and mpir I…
kuskmen
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2
votes
2 answers
Simple alternatives to floating-point when performing arithmetic on short string-encoded rationals
I am creating unit tests for a function that rounds "rational" numbers stored as strings. The current rounding implementation casts the strings to a floating point type:
#include
#include
#include…
Rogozhin
- 23
- 3
2
votes
1 answer
Is it possible to set a deterministic seed for boost::random::uniform_int_distribution<>?
I'm using boost::random::uniform_int_distribution to generate some unit tests. Notice that I'm using multiprecision, which is why I need to use boost and not the standard library. For my periodic tests, I need to…
The Quantum Physicist
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2
votes
1 answer
Building a large boost unordered_map with cpp_int
I am writing some code in c++ for a class assignment that requires work with multiprecision library such as boost. Basically, I need to build a hash table with some large integers and then lookup a certain value in that table.
When I use h, g, p…
Daniel S
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