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Release calc version 2.11.5t3

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Landon Curt Noll
2001-04-14 16:10:29 -07:00
parent 59837e385c
commit a0aba073a6
13 changed files with 913 additions and 559 deletions
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74
help/srand
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@@ -1,5 +1,5 @@
NAME
srand - seed the additive 55 shuffle pseudo-random number generator
srand - seed the subtractive 100 shuffle pseudo-random number generator
SYNOPSIS
srand([seed])
@@ -10,43 +10,43 @@ TYPES
return rand state
DESCRIPTION
Seed the pseudo-random number using an additive 55 shuffle generator.
Seed the pseudo-random number using an subtractive 100 shuffle generator.
For integer seed != 0:
Any buffered rand generator bits are flushed. The additive table
for the rand generator is loaded with the default additive table.
Any buffered rand generator bits are flushed. The subtractive table
for the rand generator is loaded with the default subtractive table.
The low order 64 bits of seed is xor-ed against each table value.
The additive table is shuffled according to seed/2^64.
The subtractive table is shuffled according to seed/2^64.
The following calc code produces the same effect on the internal
additive table:
subtractive table:
/* reload default additive table xor-ed with low 64 seed bits */
/* reload default subtractive table xor-ed with low 64 seed bits */
seed_xor = seed & ((1<<64)-1);
for (i=0; i < 55; ++i) {
additive[i] = xor(default_additive[i], seed_xor);
for (i=0; i < 100; ++i) {
subtractive[i] = xor(default_subtractive[i], seed_xor);
}
/* shuffle the additive table */
/* shuffle the subtractive table */
seed >>= 64;
for (i=55; seed > 0 && i > 0; --i) {
for (i=100; seed > 0 && i > 0; --i) {
quomod(seed, i+1, seed, j);
swap(additive[i], additive[j]);
swap(subtractive[i], subtractive[j]);
}
Seed must be >= 0. All seed values < 0 are reserved for future use.
The additive table pointers are reset to additive[23] and additive[54].
Last the shuffle table is loaded with successive values from the
additive 55 generator.
The subtractive table pointers are reset to subtractive[36]
and subtractive[99]. Last the shuffle table is loaded with
successive values from the subtractive 100 generator.
There is no limit on the size of a seed. On the other hand,
extremely large seeds require large tables and long seed times.
Using a seed in the range of [2^64, 2^64 * 55!) should be
Using a seed in the range of [2^64, 2^64 * 100!) should be
sufficient for most purposes. An easy way to stay within this
range to to use seeds that are between 21 and 93 digits, or
64 to 308 bits long.
range to to use seeds that are between 21 and 178 digits, or
64 to 588 bits long.
To help make the generator produced by seed S, significantly
different from S+1, seeds are scrambled prior to use. The
@@ -68,9 +68,9 @@ DESCRIPTION
After this call, the rand generator is restored to its initial
state after calc started.
The additive 55 pointers are reset to additive[23] and additive[54].
Last the shuffle table is loaded with successive values from the
additive 55 generator.
The subtractive 100 pointers are reset to subtractive[36]
and subtractive[99]. Last the shuffle table is loaded with
successive values from the subtractive 100 generator.
The call:
@@ -80,14 +80,14 @@ DESCRIPTION
For matrix arg:
Any buffered random bits are flushed. The additive table with the
first 55 entries of the matrix mod 2^64.
Any buffered random bits are flushed. The subtractive table with the
first 100 entries of the matrix mod 2^64.
The additive 55 pointers are reset to additive[23] and additive[54].
Last the shuffle table is loaded with successive values from the
additive 55 generator.
The subtractive 100 pointers are reset to subtractive[36]
and subtractive[99]. Last the shuffle table is loaded with
successive values from the subtractive 100 generator.
This form allows one to load the internal additive 55 generator
This form allows one to load the internal subtractive 100 generator
with user supplied values.
The randreseed64 process is NOT applied to the matrix values.
@@ -114,7 +114,7 @@ DESCRIPTION
For no arg given:
Return current a55 generator state. This call does not alter
Return current s100 generator state. This call does not alter
the generator state.
This call allows one to take a snapshot of the current generator state.
@@ -126,25 +126,25 @@ EXAMPLE
RAND state
> state = srand();
> print rand(123), rand(123), rand(123), rand(123), rand(123), rand(123);
32 60 67 71 1 77
80 95 41 78 100 27
> print rand(123), rand(123), rand(123), rand(123), rand(123), rand(123);
52 72 110 15 69 58
122 109 12 95 80 32
> state2 = srand(state);
> print rand(123), rand(123), rand(123), rand(123), rand(123), rand(123);
32 60 67 71 1 77
80 95 41 78 100 27
> print rand(123), rand(123), rand(123), rand(123), rand(123), rand(123);
52 72 110 15 69 58
122 109 12 95 80 32
> state3 = srand();
> print state3 == state2;
1
> print rand();
641407694185874626
10710588361472584495
LIMITS
for matrix arg, the matrix must have at least 55 integers
for matrix arg, the matrix must have at least 100 integers
LINK LIBRARY
RAND *zsrand(ZVALUE *pseed, MATRIX *pmat55)
RAND *zsrand(ZVALUE *pseed, MATRIX *pmat100)
RAND *zsetrand(RAND *state)
SEE ALSO
@@ -166,8 +166,8 @@ SEE ALSO
## received a copy with calc; if not, write to Free Software Foundation, Inc.
## 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
##
## @(#) $Revision: 29.2 $
## @(#) $Id: srand,v 29.2 2000/06/07 14:02:33 chongo Exp $
## @(#) $Revision: 29.3 $
## @(#) $Id: srand,v 29.3 2001/04/14 22:46:33 chongo Exp $
## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/srand,v $
##
## Under source code control: 1996/01/01 04:19:07