Subset Sum(dpss)

This is a Rust implementation that calculates subset sum problem using dynamic programming. It solves subset sum problem and returns a set of decomposed integers. It also can match corresponding numbers from two vectors and be used for Account reconciliation.

There are three ways to use this program. * CLI * Rust * Python

And it has three methods.

• find_subset
  
  • It finds a subset from an array.
• find_subset_fast_only_positive
  
  • It finds a subset from an array. It can't accept negative values but relatively faster.
• Sequence Matcher (One-to-Many)
  • It finds One-to-Many relationships with two arrays.
• Sequence Matcher (Many-to-Many)
  • It finds Many-to-Many relationships with two arrays.

dpss is short for dynamic programming subset sum.

Links

|Name|URL| |--|--| |github|https://github.com/europeanplaice/subsetsum| |crates.io|https://crates.io/crates/subsetsum| |docs.rs|https://docs.rs/subset_sum/latest/dpss/| |pypi|https://pypi.org/project/dpss/|

CLI

Installation

Binary files are provided on the Releases page. When you download one of these, please add it to your PATH manually.

Usage

Subset sum

First, you need to prepare a text file containing a set of integers like this 1 2 -3 4 5 and save it at any place.

Second, call subset_sum with the path of the text file and the target sum.

Example

Call subset_sum.exe num_set.txt 3 3
The executable's name subset_sum.exe would be different from your choice. Change this example along with your environment. The second argument is the target sum. The third argument is the maximum length of the combination.

In this example, the output is
[[2, 1], [4, -3, 2], [5, -3, 1]]

Sequence Matcher (One-to-Many)

key.txt 3 5 7

targets.txt 1 5 -3 4 5 3

Call subset_sum.exe key.txt targets.txt o2m 4
The fourth argument is the maximum length of the combination.

In this example, the output is
[(3, [3]), (5, [5]), (7, [5, 4, -3, 1])] [(3, [3]), (5, [4, 1]), (7, [5, 5, -3])] [(3, [5, -3, 1]), (5, [5]), (7, [3, 4])]

Sequence Matcher (Many-to-Many)

arr1.txt 1980 2980 3500 4000 1050

arr2.txt 1950 2900 30 80 3300 200 3980 1050 20

Call subset_sum.exe arr1.txt arr2.txt m2m 10 5 6
In this case, 10 is n_candidates that is the number of candidates to be selected. A default value is 10. 5 is max_key_length that is the maximum length of the keys as a group. A default value is a key length. 6 is max_target_length that is the maximum length of the targets as a group. A default value is a target length.

In this example, the output is
[([1050], [1050]), ([1980], [30, 1950]), ([2980], [80, 2900]), ([3500], [200, 3300]), ([4000], [20, 3980])] [([1050, 1980, 2980], [80, 1950, 3980]), ([3500], [200, 3300]), ([4000], [20, 30, 1050, 2900])]

Use in Python

installation

pip install dpss

Usage

find_subset

python import inspect import dpss help(dpss.find_subset) ```

findsubset(arr, value, maxlength, /) Finds subsets sum of a target value. It can accept negative values. # Arguments * arr - An array. * value - The value to the sum of the subset comes. * max_length - The maximum length of combinations of the answer. ```

python print(dpss.find_subset([1, -2, 3, 4, 5], 2, 3)) ```

[[4, -2], [3, -2, 1]] ```

find_subset_fast_only_positive

python help(dpss.find_subset_fast_only_positive) ```

findsubsetfastonlypositive(arr, value, maxlength, /) Finds subsets sum of a target value. It can't accept negative values but relatively faster. # Arguments * arr - An array. * value - The value to the sum of the subset comes. * max_length - The maximum length of combinations of the answer. python print(dpss.findsubsetfastonly_positive([1, 2, 3, 4, 5], 10, 4)) [[4, 3, 2, 1], [5, 3, 2], [5, 4, 1]] ```

sequence_matcher

python help(dpss.sequence_matcher) ```

sequencematcher(key, targets, maxtargetlength, /) Finds the integers from two vectors that sum to the same value. This method assumes that the two vectors have One-to-Many relationships. Each integer of the key vector corresponds to the multiple integers of the targets vector. # Arguments * key - An array. * targets - An array. * max_length - The maximum length of combinations of the answer. python print(dpss.sequencematcher([3, 5, 7], [1, 5, -3, 4, 5, 3], 4)) [ [(3, [3]), (5, [5]), (7, [5, 4, -3, 1])], [(3, [3]), (5, [4, 1]), (7, [5, 5, -3])], [(3, [5, -3, 1]), (5, [5]), (7, [3, 4])], ] ```

sequence_matcher_m2m

python help(dpss.sequence_matcher_m2m) ```

sequencematcherm2m(keys, targets, ncandidates, maxkeylength, maxtargetlength, /) Finds the integers from two vectors that sum to the same value. This method assumes that the two vectors have Many-to-Many relationships. Each integer of the keys vector corresponds to the multiple integers of the targets vector. With this method, we can find multiple combinations of the integers. n_candidates is the number of candidates to be selected. max_key_length is the maximum length of the keys as a group. Especially in long sequences, this method is very slow so n_candidates and max_key_length should be small. # Arguments * keys - An array. * targets - An array. * n_candidates - The maximum length of combinations of the answer. * max_key_length - The maximum length of combinations of the keys. * max_target_length - The maximum length of combinations of the targets. python print(dpss.sequencematcher_m2m([1980, 2980, 3500, 4000, 1050], [1950, 2900, 30, 80, 3300, 200, 3980, 1050, 20], 10, 5, 10)) [[([1050], [1050]), ([1980], [30, 1950]), ([2980], [80, 2900]), ([3500], [200, 3300]), ([4000], [20, 3980])], [([1050, 1980, 2980], [80, 1950, 3980]), ([3500], [200, 3300]), ([4000], [20, 30, 1050, 2900])]] ```

Use in Rust

Please check https://crates.io/crates/subset_sum.

Cargo.toml [dependencies] dpss = { version = "(version)", package = "subset_sum" }

Find subset

main.rs ```rust use dpss::dp::find_subset;

fn main() { let result = find_subset(&mut vec![1, 2, 3, 4, 5], 6, 3); println!("{:?}", result); } Output [[3, 2, 1], [4, 2], [5, 1]] ```

Sequence Matcher (One-to-Many)

main.rs ```rust use dpss::dp::sequence_matcher;

fn main() { let result = sequence_matcher(&mut vec![3, 5, 7], &mut vec![1, 5, -3, 4, 5, 3], 4); println!("{:?}", result); } Output [ [(3, [3]), (5, [5]), (7, [5, 4, -3, 1])] [(3, [3]), (5, [4, 1]), (7, [5, 5, -3])] [(3, [5, -3, 1]), (5, [5]), (7, [3, 4])] ] ```

Sequence Matcher (Many-to-Many)

main.rs ```rust use dpss::dp::sequencematcherm2m;

fn main() { let result = sequencematcherm2m(&mut vec![1980, 2980, 3500, 4000, 1050], &mut vec![1950, 2900, 30, 80, 3300, 200, 3980, 1050, 20], 10, 5, 10); println!("{:?}", result); } Output [([1050], [1050]), ([1980], [30, 1950]), ([2980], [80, 2900]), ([3500], [200, 3300]), ([4000], [20, 3980])] [([1050, 1980, 2980], [80, 1950, 3980]), ([3500], [200, 3300]), ([4000], [20, 30, 1050, 2900])] ```