packhorse

Welcome to packhorse, a package supporting small to medium data manipulation and analysis projects. Using packhorse, we have access to several classes that allow us to easily extract commonly used statistics, perform data manipulations such as joins, and export data into a variety of forms, such as csv and json.

Basic classes

Numeric

Instances of Numeric are list-like structures for numeric data, with properties and methods commonly used in data analysis.

Example:

final numeric = Numeric([4.57, 5.62, 4.12, 5.29, 4.64, 4.31]);
print('Variance: ${numeric.variance}');

Variance: 0.28051388888888895

Categoric

Instances of Categoric are list-like structures for categoric data, with properties and methods commonly used in data analysis.

Example:

final categoric = Categoric('mississippi'.split(''));
print('Counts:');
categoric.counts.forEach((category, count) {
  print('  $category: $count');
});
print('\nEntropy: ${categoric.entropy}');

Counts:
  i: 4
  m: 1
  p: 2
  s: 4

Entropy: 1.2636544318820964

Dataframe

Instances of Dataframe are objects containing maps of Categorics (cats) and Numerics (nums) that may be interpreted as data frames or tables of data, with each column a variable (categorization or measure) and each row an instance.

final iris = Dataframe.fromCsv(
    await File('data/iris_data.csv').readAsString());

print(iris
  .withColumns(['id', 'species', 'petal_length'])
  .withNumericFromNumeric('residuals', 'petal_length',
      (numeric) => numeric.residuals)
  .withRowsSampled(10, seed: 0));

.---.----------.------------.--------------------.
| id|   species|petal_length|           residuals|
:---+----------+------------+--------------------:
|111| virginica|         5.1|   1.341999999999997|
|147| virginica|         5.0|  1.2419999999999973|
| 79|versicolor|         4.5|  0.7419999999999973|
| 34|    setosa|         1.4| -2.3580000000000028|
| 86|versicolor|         4.5|  0.7419999999999973|
| 61|versicolor|         3.5|-0.25800000000000267|
| 40|    setosa|         1.5| -2.2580000000000027|
|119| virginica|         6.9|  3.1419999999999977|
|  8|    setosa|         1.5| -2.2580000000000027|
| 56|versicolor|         4.5|  0.7419999999999973|
'---'----------'------------'--------------------'

Thanks for your interest. Please file any issues here.