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Questions tagged [bignum]

Common computer-jargon term to refer to arbitrary-precision math and data-types. The term "arbitrary-precision" refers to the ability of a machine to perform numerical computations whose precision is limited only by the available memory.

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What is the difference between Int and Integer?

In Haskell, what is the difference between an Int and an Integer? Where is the answer documented?
0xAX
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Arbitrary-precision arithmetic Explanation

I'm trying to learn C and have come across the inability to work with REALLY big numbers (i.e., 100 digits, 1000 digits, etc.). I am aware that there exist libraries to do this, but I want to attempt to implement it myself. I just want to know if…
TT.
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How to implement big int in C++

I'd like to implement a big int class in C++ as a programming exercise—a class that can handle numbers bigger than a long int. I know that there are several open source implementations out there already, but I'd like to write my own. I'm trying to…
oneself
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Working with large numbers in PHP

To use modular exponentiation as you would require when using the Fermat Primality Test with large numbers (100,000+), it calls for some very large calculations. When I multiply two large numbers (eg: 62574 and 62574) PHP seems to cast the result to…
nickf
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What is the standard solution in JavaScript for handling big numbers (BigNum)?

Is there a bignum built into JavaScript or browsers? The alternate is loading an external library like but that seems slow and may trigger a security warning. I've considered…
David Cary
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How to deal with big numbers in javascript

I'm looking for a Mathematical solution that deals with really (long, big, huge, storms) numbers. I haven't found anything yet, But I don't wanna think that this problem hasn't be solve at this time. I'm looking for an easy Number solution, like…
crsuarezf
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What does GCC __attribute__((mode(XX)) actually do?

This arose from a question earlier today on the subject of bignum libraries and gcc specific hacks to the C language. Specifically, these two declarations were used: typedef unsigned int dword_t __attribute__((mode(DI))); On 32 bit systems…
user257111
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How can I represent a very large integer in .NET?

Does .NET come with a class capable of representing extremely large integers, such as 100 factorial? If not, what are some good third party libraries to accomplish this?
Corey
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Unable to call contract function from web3 with big number as parameter

I am trying to call a custom function of a contract that expects a parameter of unit256. I'm calling this function from web3 with this value as parameter: 10000000000000000000 (10 with 18 zeros) As soon as this call is hit by web3, I faced following…
Fariha Abbasi
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What is the standard (or best supported) big number (arbitrary precision) library for Lua?

I'm working with large numbers that I can't have rounded off. Using Lua's standard math library, there seem to be no convenient way to preserve precision past some internal limit. I also see there are several libraries that can be loaded to work…
Jon 'links in bio' Ericson
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Can long integer routines benefit from SSE?

I'm still working on routines for arbitrary long integers in C++. So far, I have implemented addition/subtraction and multiplication for 64-bit Intel CPUs. Everything works fine, but I wondered if I can speed it a bit by using SSE. I browsed through…
cxxl
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Recursive function calculating factorials leads to stack overflow

I tried a recursive factorial algorithm in Rust. I use this version of the compiler: rustc 1.12.0 (3191fbae9 2016-09-23) cargo 0.13.0-nightly (109cb7c 2016-08-19) Code: extern crate num_bigint; extern crate num_traits; use num_bigint::{BigUint,…
mrLSD
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AVX VMOVDQA slower than two SSE MOVDQA?

While I was working on my fast ADD loop (Speed up x64 assembler ADD loop), I was testing memory access with SSE and AVX instructions. To add I have to read two inputs and produce one output. So I wrote a dummy routine that reads two x64 values…
cxxl
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Best bignum library to solve Project Euler problems in C++?

I am still a student, and I find project Euler very fun. sometimes the question requires calculations that are bigger than primitive types. I know you can implement it but I am too lazy to do this, So I tried few libraries, MAPM :: very good…
Khaled Alshaya
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Fast bignum square computation

To speed up my bignum divisons I need to speed up operation y = x^2 for bigints which are represented as dynamic arrays of unsigned DWORDs. To be clear: DWORD x[n+1] = { LSW, ......, MSW }; where n+1 is number of used DWORDs so value of number x =…
Spektre
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