biginteger

问题 Due to mathematica constraints I've to use the BigInteger class to represent values. After some calculations I would like to store the result (given by 2x BigInteger instances) into Mysql... What is the best datatype to store such object ? I was thinking about using a Blob to store the binary format of those results (128 bits) ? But I would like to avoid unnecessary type conversions. 回答1: I would recommend using a Blob and then the BigInteger(byte[] val) constructor to go from byte array to

问题 I'm writing an app which involves arithmetic with humongous numbers, with very many digits. I've previously written a class that simplifies handling big numbers by defining them as strings and then using slow arithmetic string functions. Is this the best way to do it? If not, how should I approach this problem? Does C# have anything built-in for such situations? 回答1: .NET 4 will have this built in via the BigInteger type. This is claimed to be pretty well tuned and should perform very well.

问题 I'm writing an app which involves arithmetic with humongous numbers, with very many digits. I've previously written a class that simplifies handling big numbers by defining them as strings and then using slow arithmetic string functions. Is this the best way to do it? If not, how should I approach this problem? Does C# have anything built-in for such situations? 回答1: .NET 4 will have this built in via the BigInteger type. This is claimed to be pretty well tuned and should perform very well.

问题 In Java, most of the primitive types are signed (one bit is used to represent the +/-), and therefore when I exceed the limits of the type, I can get unexpected results, like negative numbers. Is there any better solution than using BigInteger for this, since BigInteger has performance issues and you need to use the class methods for basic arithmetic instead of the language operators (ruins readability)? 回答1: No, there is not a better solution. If you are working with values that cannot fit

问题 I'm looking for a replacement of the stock Delphi Data.FmtBcd library because I just hit its limits like maximum decimal digits it can represent and program terminates with EBcdOverflowException . For the curious, I'm calculating arithmetic series members and need to handle very large numbers - hundred-thousands positions are not so uncommon. And also get results in a reasonable time. I did rewritten part of the code to Python 3.2 for the testing purposes and calculation speed would be

问题 This is my Sender entity @Entity public class Sender { @Id @GeneratedValue(strategy = GenerationType.AUTO) private long senderId; ... ... public long getSenderId() { return senderId; } public void setSenderId(long senderId) { this.senderId = senderId; } } When I try to execute following query: StringBuilder query = new StringBuilder(); query.append("Select sender.* "); query.append("From sender "); query.append("INNER JOIN coupledsender_subscriber "); query.append("ON coupledsender_subscriber

问题 I am trying to compare if the value of one BigInteger(base) is > the value of another BigInteger(prime) and if the value of 'a' is not equal to one. If value of a is not 1, it should break out of the loop. How should i compare them? Random ran = new Random(); BigInteger prime = new BigInteger(16,ran); BigInteger base,a,one; one = new BigInteger("1"); for (int i = 0; i < 65535; i++){ while (base>prime){ base = new BigInteger(16,ran); } a = base.modPow(prime.subtract(one),prime); System.out

问题 I've been searching around for quite a while, and I've found almost nothing on how BigInteger actually holds its numbers. Are they an array of chars? Something else? And how is data converted to/from BigInteger ? From what I've found, I am assuming that all of arbitrary precision classes, like BigInteger and BigDecimal , hold data as a character array. Is this how it actually works? Or is it just people's guess? I'm asking because I have been working on my own implementation of something like

问题 I'm trying to implement BigInt and have read some threads and articles regarding it, most of them suggested to use higher bases(256 or 2^32 or even 2^64). Why higher bases are good for this purpose? Other question I have is how am I supposed to convert a string into higher base(>16). I read there is no standard way, except for base64. And the last question, how do I use those higher bases. Some examples would be great. 回答1: The CPU cycles spent multiplying or adding a number that fits in a

问题 I need to convert a string to BigInt like BigInteger in Javascript Example var reqId = "78099864177253771992779766288266836166272662"; var result = parseInt(reqId); document.write(result); Resultant value not matching since JavaScript only allows integers up to (2^53)-1. Is there any way to overcome this? 回答1: BigInt is now a native JavaScript language feature. It's at Stage 3 in the TC39 process and it's shipping in V8 v6.7 and Chrome 67. To turn a string containing a valid numeric literal