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Release calc version 2.11.0t10

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Landon Curt Noll
1999-11-11 05:15:39 -08:00
parent 86c8e6dcf1
commit 96c34adee3
283 changed files with 2380 additions and 3032 deletions
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help/rand
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@@ -19,7 +19,7 @@ DESCRIPTION
pseudo-random generator. If you need a fast generator and do not
need a cryptographically strong one, this generator is likely to do
the job. Casual direct use of the shuffle generator may be
acceptable. For a much higher quality cryptographically strong
acceptable. For a much higher quality cryptographically strong
(but slower) generator use the Blum-Blum-Shub generator (see the
random help page).
@@ -55,9 +55,9 @@ DESCRIPTION
by Knuth, Vol 2, 2nd edition (1981), Section 3.2.2, page 32,
Algorithm B.
The rand generator has a good period, and is fast. It is reasonable as
The rand generator has a good period, and is fast. It is reasonable as
generators go, though there are better ones available. The shuffle
method has a very good period, and is fast. It is fairly good as
method has a very good period, and is fast. It is fairly good as
generators go, particularly when it is feed reasonably random
numbers. Because of this, we use feed values from the additive 55
method into the shuffle method.
@@ -120,7 +120,7 @@ DESCRIPTION
perceptions that are noted above.
It should be noted that the purpose of randreseed64 is to scramble a
seed ONLY. We do not care if these generators produce good random
seed ONLY. We do not care if these generators produce good random
numbers. We only want to help eliminate the human factors & perceptions
noted above.
@@ -144,8 +144,8 @@ DESCRIPTION
We will select the randreseed64 multiplier 'a' such that:
a mod 8 == 5 (based on note iii)
0.01*m < a < 0.99*m (based on note iv)
a mod 8 == 5 (based on note iii)
0.01*m < a < 0.99*m (based on note iv)
0.01*2^64 < a < 0.99*2^64
a is prime (help keep the generators independent)
@@ -159,10 +159,10 @@ DESCRIPTION
gcd(a, c) == 1 (adders & multipliers will be more independent)
The values 'a' and 'c for randreseed64 are taken from the Rand book
of numbers. Because m=2^64 is 20 decimal digits long, we will
of numbers. Because m=2^64 is 20 decimal digits long, we will
search the Rand book of numbers 20 at a time. We will skip any of
the 55 values that were used to initialize the additive 55
generators. The values obtained from the Rand book are:
generators. The values obtained from the Rand book are:
a = 6316878969928993981
c = 1363042948800878693
@@ -180,12 +180,12 @@ DESCRIPTION
One might object to the complexity of the seed scramble/mapping via
the randreseed64 process. But Calling srand(0) with the randreseed64
process would be the same as calling srand(10239951819489363767)
without it. No extra security is gained or reduced by using the
without it. No extra security is gained or reduced by using the
randreseed64 process. The meaning of seeds are exchanged, but not
lost or favored (used by more than one input seed).
The randreseed64 process does not reduce the security of the rand
generator. Every seed is converted into a different unique seed.
generator. Every seed is converted into a different unique seed.
No seed is ignored or favored.
The truly paranoid might suggest that my claims in the MAGIC NUMBERS