| Title: | Improved Random Number Generator Seeding |
| Version: | 0.1.0 |
| Description: | A procedure for seeding R's built in random number generators using a variable-length sequence of values. Accumulates input entropy into a 256-bit hash digest or "ironseed" and is able to generate a variable-length sequence of output seeds from an ironseed. |
| License: | MIT + file LICENSE |
| Language: | en-US |
| Encoding: | UTF-8 |
| RoxygenNote: | 7.3.2 |
| Biarch: | TRUE |
| NeedsCompilation: | yes |
| URL: | https://github.com/reedacartwright/ironseed |
| BugReports: | https://github.com/reedacartwright/ironseed/issues |
| Suggests: | tinytest |
| Packaged: | 2025-07-06 21:50:57 UTC; reed |
| Author: | Reed Cartwright 
[aut, cre] |
| Maintainer: | Reed Cartwright <racartwright@gmail.com> |
| Repository: | CRAN |
| Date/Publication: | 2025-07-11 08:40:02 UTC |
Ironseed: Improved Random Number Generator Seeding
Description
A procedure for seeding R's built in random number generators using a variable-length sequence of values. Accumulates input entropy into a 256-bit hash digest or "ironseed" and is able to generate a variable-length sequence of output seeds from an ironseed.
Author(s)
Maintainer: Reed Cartwright racartwright@gmail.com (ORCID)
See Also
Useful links:
Report bugs at https://github.com/reedacartwright/ironseed/issues
Initialize .Random.seed
Description
Initialize .Random.seed
Usage
fill_random_seed(x, quiet = FALSE)
has_random_seed()
get_random_seed()
set_random_seed(seed)
Arguments
x |
an ironseed. |
quiet |
a logical indicating whether to silence messages. |
seed |
a previous |
Value
fill_random_seed() returns the previous value of .Random.seed or
NULL.
Ironseed: Improved Random Number Generator Seeding
Description
An ironseed is a 256-bit hash digest constructed from a variable-length input sequence and can be used to generate a variable-length output sequence of seeds, including initializing R's built-in random number generator.
-
ironseed()creates an ironseed from user supplied objects or automatically from multiple sources of entropy on the local system. It also initializes R's built-in random number generator from an ironseed. -
create_seqseq()uses an ironseed to generate a sequence of 32-bit seeds. -
is_ironseed()tests whether an object is an ironseed, andis_ironseed_str()tests if it is a string representing and ironseed. -
as_ironseed()casts an object to an ironseed, andparse_ironseed_str()parses a string to an ironseed.
Usage
ironseed(..., set_seed = !has_random_seed(), quiet = FALSE)
create_seedseq(fe, n)
is_ironseed(x)
is_ironseed_str(x)
as_ironseed(x)
parse_ironseed_str(x)
Arguments
... |
objects |
set_seed |
a logical indicating whether to initialize |
quiet |
a logical indicating whether to silence messages. |
fe |
an ironseed |
n |
a scalar integer specifying the number of seeds to generate |
x |
a string, ironseed, or other object |
Details
Ironseeds have a specific string representation, e.g. "rBQSjhjYv1d-z8dfMATEicf-sw1NSWAvVDi-bQaKSKKQmz1", where each element is a 64-bit number encoded in little-endian base58 format.
Parameter set_seed defaults to TRUE if .Random.seed does not already
exist and FALSE otherwise.
Ironseed behaves differently depending on the number of arguments passed as
....
0 arguments: If initialization is enabled,
ironseed()generates an automatic ironseed. Otherwise,ironseed()returns the last ironseed used to initialize.Random.seed.1 argument:
ironseed(NULL)generates an automatic ironseed. Forironseed(x), ifxis an ironseed object, it is used as is. Ifx, is a scalar character that matches an ironseed string, it is parsed to an ironseed. Otherwise,xhashed to create an ironseed.2+ arguments:
ironseed(x,y,...)hashes the arguments to create an ironseed.
An ironseed is a finite-entropy (or fixed-entropy) hash digest that can be used to generate an unlimited sequence of seeds for initializing the state of a random number generator. It is inspired by the work of M.E. O’Neill and others.
An ironseed is a 256-bit hash digest constructed from a variable-length sequence of 32-bit inputs. Each ironseed consists of eight 32-bit sub-digests. The sub-digests are 32-bit multilinear hashes that accumulate entropy from the input sequence. Each input is included in every sub-digest. The coefficients for the multilinear hashes are generated by a Weyl sequence.
Multilinear hashes are also used to generate an output seed sequence from an ironseed. Each 32-bit output value is generated by uniquely hashing the sub-digests. The coefficients for the output are generated by a second Weyl sequence.
Value
An ironseed. If .Random.seed was initialized, the ironseed used
will be returned invisibly.
References
O’Neill (2015) Developing a seed_seq Alternative. https://www.pcg-random.org/posts/developing-a-seed_seq-alternative.html
O’Neill (2015) Simple Portable C++ Seed Entropy. https://www.pcg-random.org/posts/simple-portable-cpp-seed-entropy.html
O’Neill (2015) Random-Number Utilities. https://gist.github.com/imneme/540829265469e673d045
Lemire and Kaser (2018) Strongly universal string hashing is fast. http://arxiv.org/pdf/1202.4961
Weyl Sequence https://en.wikipedia.org/wiki/Weyl_sequence
See Also
Examples
# Generate an ironseed with user supplied data
ironseed::ironseed("Experiment", 20251031, 1)
# Generate an ironseed automatically and initialize `.Random.seed` with it
ironseed::ironseed(set_seed = TRUE)