Version 0.3-1
2015-01-24  (dedicated to my brothers Stefan's 50 birthday)
   - Major code revision to reflect the internal changes in upcoming 
     PowerTOST V1.2-06 'raw' power functions
   - Sample-size estimation routine (vectorized!) reworked which gives
     a considerable run-time boost
   - Internal change of start value of sample size estimation to Zhang's
     formula (may change the extremal value of n and its mean if usePE=TRUE)
   - Function power.2stage.p() accepts now unbalanced stage 1 and uses the 
     correct power of Welch's test in the power monitoring stepsand in 
     sample size estimation
   - Former function power.2stage.p() now available as power.2stage.pAF()
     which does the calculations exactly as described in A.Fuglsang's paper 
Version 0.2-2
2014-12-08
   - CRAN version of V0.2-1 with two nasty bugs removed.
Version 0.2-1
2014-12-06   (Dedicated to my daughter Antje's 40 birthday)
released to alpha-testers only
   - Depreciated function power.2stage.Bf() removed
   - Functions power.2stage() and power.2stage.fC() now have an argument
     min.n2 to restrict the sample size for stage 2 to a lower limit
   - Calculation of % studies in stage 2 re-defined to studies having total n>n1
     (was in the past studies which had to be evaluated with alpha2, affects 
      only 'unsymmetrical' alpha settings)
   - Function power.2stage.ssr() for (blinded) sample size re-estimation added
     (2-stage design without BE decision at interim)
   - Some code streamlining
   - Some enhancements and unification of output of power functions
Version 0.1-5
2014-10-09
   - power.2stage.Bf() reworked into the new function power.2stage.fC() to 
     include Potvin method "C" and to include an additional futility criterion 
     for the CI also. power.2stage.Bf() is depreciated and will not be contained 
     in one of the next versions. Use power.2stage.fC() instead.
Version 0.1-4
2014-07-24
   - Bug in power.2stage.GS() removed which prevented the convergence of power
     values with increasing number of sims
Version 0.1-3
2014-07-02
   - Power calculation method "shifted" added in power.2stage() to the aim 
     of comparison to Potvin et al.
   - Internal change of start value of sample size search to avoid 
     failed searches if variability is high and theta0 is near 1.
Version 0.1-2
not released to the public
   - Special version to alpha testers
Version 0.1-1
2014-05-08 released via CRAN
2014-04-24 release to alpha testers
   - Contains now the function power.2stage.p() for calculation of power in
     BE studies with sequential (2-stage) designs with 2 parallel groups.
   - Some internal code streamlinig.
Version 0.0-8
2014-04-11
   - Bug in power.2stage.KM() removed if using method="B" (Karalis TSD-2).
     Thanks again and again to Helmut Schuetz!
   - Man page of power.2stage.KM() changed to the correct definition of
     the Karalis/Macheras TSD or Karalis TSD-1, TSD-2 respectively.
Version 0.0-7
2014-02-13
   - Maintenance release to reflect the changes in PowerTOST V1.1-10.
   - Contains now the function power.2stage.GS() for non-adaptive group
     sequential (2-stage) BE studies.
Version 0.0-6
2014-01-02 
   - Examples adapted to complain with CRAN policy "Examples should run for 
     no more than a few seconds each". Few seconds means below 5 sec as I learned.
     Attention! Number of sims are too low to have meaningfull results.
     Minimum number of sims should be 1E5 for 'power', 1E6 sims for 'alpha'.
Version 0.0-5
2013-12-27 
   - First attempt to release via CRAN
Version 0.0-4
2013-09-12 not released, internal version only
   - Function power2.2stage() renamed to power.2stage.KM()
   - Arguments in power.2stage.KM() omitted which are not necessary for
     the TSD's described in the Karalis & Macheras and in Karalis papers 
     (see references).
   - Default method in power.2stage.KM() shifted to "C".
   - Function power.2stage.Bf() implemented which evaluates a 2-stage design
     derived from Potvin method 'B' with a futility criterion for the PE
     of stage 1.
Version 0.0-3
2013-09-03 released to alpha testers
   - function power2.2stage() implemented which uses PE and MSE of stage 1
     also for the power calculation steps if usePE=TRUE
Version 0.0-2
2013-07-10 released to alpha testers
   - Default for npct argument changed to c(0.05, 0.5, 0.95) in accordance
     with the Potvin papers.
   - Cases with n(total)>Nmax now counted at stage 1 since I feel this is more
     logical.
   - More checks of input added (THX to Helmut Schuetz).
   - Bug in output removed claiming that sample size is estimated with PE 
     & mse from stage 1 even if argument usePE=FALSE (THX to Helmut).
   - Internally stage vector introduced and output based on that.
version 0.0-1
2013-07-09
   - First release to alpha testers