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2025-10-25Add Regular Complexity to Compact ViewAdrien Hopkins
2025-09-22Update copyright years using Git historyv1.0.0rc2Adrien Hopkins
2025-09-22Add option to show logarithmic RCAdrien Hopkins
This makes finding the RC of prime powers multiplication instead of exponentation, which is much easier to do mentally.
2025-09-22Show regular complexity of prime factorsAdrien Hopkins
This metric shows how many combinations you'll need to memorize prime powers, and how big the numbers are in complementary multiplication. The YouTube video "the best way to count" inspired me to think I need a metric to handle both size and factors, but the specific metric is entirely original (or at least independently discovered).
2024-11-20Add reciprocoal logarithm to non-compact viewAdrien Hopkins
Although I have the regular logarithm, its reciprocoal is useful to determine the length of numbers in a certain radix. Like with the totative ratio (where both it and its reciprocoal are useful), I showed both in the regular view and only one in the compact view.
2024-11-20Change logarithms to binaryAdrien Hopkins
After thinking about how I want to best represent logarithms, I think the best way is to see them as equivalent to the size of a digit. Binary logarithms allow for using a familiar unit (bits) to represent this size. Nepers exist for the natural logarithm, but almost no one uses them. Also, because binary is the smallest base out there, this value will always be ≥1. This means I'm making the most out of my digits! This does mean that digit length isn't immediately obvious, but this is the same idea as "1 km = 1000 m" meaning that the number of km is 1/1000 the number of m - using the regular logarithm is like associating the km with the number 1000, using the reciprocoal is like associating it with 1/1000=0.001. Documentation has been changed to reflect this.
2023-11-12Add per-file copyright notices & contact infoAdrien Hopkins
This is the safest thing to do to ensure my software is free while avoiding legal trouble ... hopefully, I'm not a lawyer!
2023-11-09Reduce golang requirement to go1.18Adrien Hopkins
go1.21, the previous requirement, was released a few months ago, so not all systems have adopted it. go1.18 is old enough that most systems should support it, but it introduces generics, which my testing code is highly dependent on, so I can't easily go any earlier.
2023-10-09factors: Give Type proper name & zero valueAdrien Hopkins
2023-09-14Bump version to 1.0.0-beta & gofmtv1.0.0bAdrien Hopkins
2023-09-07Add regular util. score, replace in compact viewAdrien Hopkins
The RUS is like the factor utility score, but for regulars (numbers divisible by any power of the radix) instead of factors (numbers divisible by the radix). It estimates the utility of fractions that terminate but with more than one digit, like 4, 8 and 20 in decimal. It is also (by coincidence) the reciprocoal of the totative ratio. I am replacing it in the compact view because it is more useful, for two reasons: - It can be meaningfully compared with the factor utility score. By subtracting RUS-FUS, you can find the utility of non-factor regulars. This score can give a hint about how often these fractions will be used in a radix. It also can tell you how much benefit you can get from adding another copy of a radix's prime factors. For example, senary (RUS-FUS=1.0) can gain a lot from adding another 2 or 3, while octal (RUS-FUS=0.125) probably won't (in terms of factors at least, the benefits for computers are separate to this) - Because of the way they are calculated, the RUS is far more likely to be a round/terminating decimal than the totative ratio. This means that taking the reciprocoal to get the benefits of the other number is far easier with the RUS than the totative ratio.
2023-09-07Add ability to display specific totative digitsAdrien Hopkins
Instead of just saying how many totative digits there are, the new -t flag allows the user to determine the specific digits. All totatives will end in one of these digits, and all primes are either factors or totatives. This feature is not useful in comparing radices, only learning one you have already chosen. Because there can be so many totatives (p - 1 of them for primes!), this is not displayed by default. The digit map (without -f) gives this information, and beyond its range every number will have more than 8 totatives, so do not use this flag if you only want the count.
2023-09-07Calculate type of all radices without -lAdrien Hopkins
factors.Type now supports all numbers; I have used lookup arrays instead of determining whether a number is SAN or not. There are only 117 elements to store, and this makes the algorithm Θ(1), so it's an improvement. Also, I have changed the size of some integer values to correspond to this change - they now indicate the size of numbers they can accept. The only outputs that are hidden for large radices are: - The digit map, which goes up to 36 because I don't have any more digits beyond that point - The multiplication table complexity, which is estimated above 2^16 (for performance), and can optionally be extended to 2^32 (above this, the output could overflow a uint64).
2023-09-07Standardize naming in compact viewAdrien Hopkins
- Use 'r' instead of 'n' as variable name for radix - Use 'ln' instead of 'Ln' Both of these are for consistency.
2023-09-05Unexport everything outside factors pkgAdrien Hopkins
because it's not public API!
2023-09-05Treat radices >2^16 as large unless -l setAdrien Hopkins
These radices are large enough that: - there is no reason to use them as actual radices - calculating them takes a lot of time! Therefore, the exact MTC and radix type shouldn't be calculated by default. If you want to take the time, you still can with -l. I am keeping the original 2^32 limit even with -l, because the problem with that is not performance, it is that the resulting MTC could overflow a uint64 (also the CAN list only goes up to this range).
2023-09-05Add lower bound estimate for massive MTCsAdrien Hopkins
This can easily be estimated from existing information, so it's useful to have, even in the compact view. This estimate is more accurate (narrows the range down further) the higher the radix's totative ratio. It also should be closer to the actual value than the upper bound.
2023-09-05Remove totative ratio from factors APIAdrien Hopkins
This value can easily be calculated as φ(r)/r. There is no need to have this now that I have a function φ(r) (renamed to its mathematical name, Totient). I removed totative ratio instead of totient because, while it is more important, totient is an integer while totative ratio is a float. This means that the totative ratio can be calculated exactly from the totient, but not the other way round.
2023-09-04Add ability to show full digit mapsAdrien Hopkins
Full digit maps will show every digit from 0 to 35, regardless of the radix. This allows you to see extra fractions for small radices and to get a digit map for radices above 36. This isn't enabled by default because the extra "digits" added for small radices aren't actually digits - so it may be unintuitive. There are also some situations where only a radix's actual digits matter, such as multiplication tables.
2023-09-04Rearrange order of components in outputAdrien Hopkins
In general, components go in the order Factors → Totatives → Size. 2345 Score was moved to fit this order, since it concerns both factors (2-5) and totatives (5). The compact view was rearranged to have a consistent order with the normal view. Also I added the MTC estimate for very large radices into the compact view, because it can be there.
2023-09-04Remove 2345 Score from compact outputAdrien Hopkins
The compact output attempts to maximize the power-to-weight ratio of this program, and the 2345 Score does not do this: - It can already be easily determined from the prime factorization and decimal radix, or trivially determined from the digit map. - It does not take mixed radices (the radices you'll need to use bases large enough to not show a digit map) into account. - Although a big part of the 2345 Rank is strict improvements, some of the decisions made in its design were necessarily arbitrary. The alternatives give a more objective view. The normal output is about showing everything worth showing, and the 2345 score is still useful there (especially for making sense of the resulting complexity), so it is not removed from there.
2023-09-04Add totative digit count to non-compact outputAdrien Hopkins
This is done for a few reasons: - Allow the user to easily determine the exact value of the totative ratio - This information is important when the digit map isn't accessible (for radices >36) - More consistency with factors I don't show the exact values of totatives like I do with factors because they're far more common - the superior highly composite (i.e. one of the numbers with the highest factor count) number 720720 has 240 factors and 138240 totatives, for example.
2023-08-30Raise precision in non-compact displayAdrien Hopkins
The non-compact display is intended as a "full info" display, so it makes sense to have more precision in these numbers. The compact display is unchanged.
2023-08-30Add compact displayAdrien Hopkins
2023-08-30Extract factor info into separate structAdrien Hopkins
This achieves two things: - Decouples my code by putting the printing code into its own file - Makes it easier to make alternate ways of printing (e.g. a compact mode)