Go to the first, previous, next, last section, table of contents.
-
In the strict mode, the performance of Numerics.Float_Random and
Numerics.Discrete_Random shall be as specified here.
Implementation Requirements
-
Two different calls to the time-dependent Reset procedure shall reset
the generator to different states, provided that the calls are separated
in time by at least one second and not more than fifty years.
-
The implementation's representations of generator states and its
algorithms for generating random numbers shall yield a period of at
least 2**31-2; much longer periods are desirable but not required.
-
The implementations of Numerics.Float_Random.Random and
Numerics.Discrete_Random.Random shall pass at least 85% of the
individual trials in a suite of statistical tests. For
Numerics.Float_Random, the tests are applied directly to the floating
point values generated (i.e., they are not converted to integers first),
while for Numerics.Discrete_Random they are applied to the generated
values of various discrete types. Each test suite performs 6 different
tests, with each test repeated 10 times, yielding a total of 60
individual trials. An individual trial is deemed to pass if the
chi-square value (or other statistic) calculated for the observed counts
or distribution falls within the range of values corresponding to the
2.5 and 97.5 percentage points for the relevant degrees of freedom
(i.e., it shall be neither too high nor too low). For the purpose of
determining the degrees of freedom, measurement categories are combined
whenever the expected counts are fewer than 5.
Go to the first, previous, next, last section, table of contents.