ubigintschangehistory.txt

Delphi for fun library v12, latest. This is the library for manuplating list, combination-permutati

{Changes Jan 2007 by GDD
    * Added variations of "Divide With Remainder" operations to include
      DivideRemFloor and DivideRemEuclidean in addition to the standard
      DivideRem which uses truncated divide.

    * Added "Scratchpad: memory management to improve handling large integers used
      witihn routine to hold interim results.
      
    * Moved procedures  ShiftLeftBase10, ShiftRightBase10, ShiftLeftNum,
      and ShiftRightNum to UBigFloat unit for use in TFloatInt integer class used
      by TBigFloat.

 }

 {additions by Hans Klein 2005([e-mail])
        Procedures:
          pow(const exponent:Int64);
          square;
          sqroot;
          gcd(i2:tinteger);
          gcd(i2:Int64);
          shiftleft: fast multiplication by base;
          modpow(const e,m:Tinteger);
          invmod(I2:Tinteger);
        Functions:
          shiftright: fast division by base; result=remainder;
          isodd:boolean;
          IsProbablyPrime:boolean;
 }
 {Changes by Charles Doumar September 2005
  Copyright 2005, Charles Doumar
        Rewrites or Additions:
          ConvertToDecimalString(commas:boolean); (total rewrite)
          mult(i2:tinteger) (total rewrite);
          mult(const I2:int64); (total rewrite);
          square (total rewrite);
          Nroot(const root: integer); : find the Nth root of an integer (New)
          abscompare(I2:Int64):integer; (new function)
          GetBase: integer;
          IsZero:boolean;
          CompareZero:integer; {Changed to IsZero for consistency
          AssignOne;
          AssignZero;
          ShiftLeftBase10(num: integer);
          ShiftRightBase10(num: integer);
          ShiftLeftNum(num: integer);
          ShiftRightNum(num: integer);
        Optimizations:
          trim - remove condition from loop, check for sign = 0 when val=0
          Assign(Const i2:Int64);  - remove MOD statements
          Assign(const i2:string); - remove MOD statements
          dividerem(const I2:TInteger; var remain:TInteger); - remove MOD statements
          pow(const exponent:Int64);  - remove MOD, call square, remove div
          isodd - remove MOD statement
          absadd - removed MOD statements
          ConvertToDecimalString - removed Mod Statements
          Sqroot; - call new Nroot function
         Bug fixes
          converttoInt64(n: Int64); - fixed overflow problem, fixed sign problem
          invmod - fixed failure to free memory problem
          dividerem - change remainder to 0 when divisor is 0
          fixed various sign functions....

}

{Changes made by Hans Klein Oct 2005, can be found by searching for hk
added
        divide2: handles efficient division by 2.
        divmodsmall(int 64, var int64)
        assignsmall(int 64)
                these two procedures handle integers less than base more efficient;
modified to use these procedures:
        assign(int64)
        modulo(int64)
        modulo(tinteger)
        divide(int64)
        divide(tinteger)
modified and partially rewritten
        modpow
        gcd
optimized:
        isprobablyprime:
          uses divide2
          first factors out small factors using divmodsmall
changed setbaseval(1000) to SetbaseVal(100000);
          }
{Changes made by Charles Doumar Jan 2005

Added:
    AbsoluteValue: make negative number positive
Bug fixes:
    DigitCount: Now correctly counts digits...
    Assign:  Now works with different bases ...
    ShiftLeftBase10: ensure digits Array is set...
    ShiftRightBase10: correctly count digits...

optimized:
    Square:  faster
    Mult:  Faster

}