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  GAP 4.4 Update 8 (September 2006)   
                  
    New or improved functionality     
                  
   1. A function Positions with underlying operation      
      PositionsOp, which returns the list of all          
      positions at which a given object appears in a      
      given list. 
   2. LogFFE now returns `fail' when the element is not a 
      power of the base.
   3. It is now allowed to continue long integers,        
      strings or identifiers by ending a line with a      
      backslash or with a backslash and carriage return   
      character. So, files with GAP code and              
      DOS/Windows-style line breaks are now valid input   
      on all architectures.           
   4. The command line for starting the session and the   
      system environment are now available in             
      GAPInfo.SystemCommandLine and   
      GAPInfo.SystemEnvironment.      
   5. Names of all bound global variables and all          
      component names are available on GAP level.         
   6. Added a few new Conway polynomials computed by Kate 
      Minola and John Bray.           
   7. There is a new concept of random sources, see       
      IsRandomSource, which provides random number        
      generators which are independent of each other.
      
      There is kernel code for the Mersenne twister       
      random number generator (based on the code by       
      Makoto Matsumoto distributed at
      http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html).
      It provides fast 32 bit pseudo random integers with
      a period of length 2^19937-1 and a 623-dimensional              
      equidistribution. The library methods for random    
      elements of lists and for random (long) integers    
      (Random(low, high)) are using the Mersenne twister  
      now.
                  
   8. In line editing mode (usual input mode without -n   
      option) in lines starting with gap> , > or brk>     
      this beginning part is immediately removed. This is 
      a convenient feature that allows one to cut and     
      paste input lines from other sessions or from       
      manual examples into the current session.           

    Fixed bugs which could produce wrong results          
                  
   1. The function Decomposition returned coefficient     
      vectors also in certain situations where in fact no 
      decomposition exists. This happened only if the     
      matrix entered as the first argument contained      
      irrational values and a row in the matrix entered   
      as the second argument did not respect the          
      algebraic conjugacy relations between the columns   
      of the first argument. So there was no problem for  
      the usual cases that the two matrices are integral  
      or that they are lists of Brauer characters.        
      [Reported by J"urgen M"uller]   
   2. PC group homomorphisms can claim a wrong kernel     
      after composition. [Reported by S.Bouc]             
   3. The return value of OctaveAlgebra had an            
      inconsistent defining structure constants table for 
      the case of coefficients fields not containing the  
      integer zero. [Reported by G'abor Nagy]             
   4. The manual guarantees that a conjugator             
      automorphism has a conjugating element in the group 
      if possible. This was not guaranteed.               
   5. StabChain for symmetric groups gave a wrong result  
      if fixed points were prescribed for base.           
   6. Contrary to what is documented the function         
      POW_OBJ_INT returned an immutable result for        
      POW_OBJ_INT(m,1) for a mutable object m. This is    
      triggered by the code m^1.      
   7. PseudoRandom for a group had a problem if the group 
      had lots of equal generators. The produced elements 
      were extremely poorly distributed in that case. This   
      is now fixed for the case that elements of the      
      group can easily be sorted.     
   8. Fixed the bug that the type of a blist was computed 
      wrongly: The type previously had IS_PLIST_REP       
      instead of IS_BLIST_REP in its filter list.         
   9. `Orbits' did not respect a special                  
      `PositionCanonical' method for right transversals.  
      [Reported by Steve Costenoble]  
  10. Wrong results for GcdInt for some arguments on 64   
      bit systems only. [Reported by Robert Morse]        
  11. When prescribing a subgroup to be included, the low 
      index algorithm for fp groups sometimes returned    
      subgroups which are in fact conjugate. (No          
      subgroups are missing.) [Reported by I.Soroko]      
                  
    Fixed bugs which could lead to crashes                
                  
   1. The command line option -x allowed arguments > 256  
      which can then result in internal buffers           
      overflowing. Can't really test it except by         
      starting gap -x 300 and checking SizeScreen(); With 
      the fix it is [256,24], without it was [300,24]     
      [Reported by Michael Hartley]   
                  
    Other fixed bugs                  

   1. Two special methods for the operation               
      CompositionMapping2 were not correct, such that     
      composing (and multiplying) certain group           
      homomorphisms did not work. [Reported by Peter      
      Mayr]       
   2. In the definition of FrobeniusCharacterValue, it    
      had been stated erroneously that the value must lie 
      in the field of p^n-th roots of unity; the correct  
      condition is that the value must lie in the field   
      of (p^n-1)-th roots of unity. [Reported by Jack     
      Schmidt]    
   3. The function DirectProduct failed when one of the   
      factors was known to be infinite.                   
   4. For a linear action homomorphism PreImageElm was    
      very slow because there was no good method to check 
      for injectivity, which is needed for nearly all     
      good methods for PreImageElm. This change adds such 
      a new method for IsInjective. [Reported by Akos     
      Seress]     
   5. Rare errors in the complement routine for           
      permutation groups.             
   6. Blocks code now uses jellyfish-style random         
      elements to avoid bad schreier trees                
   7. A method for IsPolycyclicGroup has been added. Such 
      a method was missing so far.    
   8. Corrected EpimorphismSchurCover to handle the       
      trivial group correctly. Added new methods that     
      follow immediately from computing the Schur Cover   
      of a group. The attribute Epicentre, the operations 
      NonabelianExteriorSquare and    
      EpimorphismNonabelianExteriorSquare, and the        
      property IsCentralFactor are added to the library   
      with documentation and references.                  
   9. Display the correct expression in a call stack      
      trace if an operation was called somewhere up due   
      to the evaluation of a unary or binary operation.   
  10. Made StripMemory an operation rather than a global  
      function. Added ForgetMemory operation.             
  11. Adjust things slightly to make later conversion to  
      new vectors/matrices easier. Nothing of this should 
      be visible. 
  12. Corrected some details in the documentation of the  
      GAP language. [Reported by AK]  
  13. Now PositionSorted is much faster on long mutable   
      plain lists. (The former operation is substituted   
      by a function and a new operation                   
      PositionSortedOp.) [Reported by Radu Silviu]        
  14. Now it is possible to switch repeated warnings off  
      when working with iterative polynomial rings.       
                  

     ----------------------------------------------------------------------
  
   The GAP Group, September 2006.