starfruit 0.2.1

A mathematical library extending and bettering provided dart and dart:math functions.

Starfruit

A library containing useful utilities, efficiencies, and abstractions to improve over the Dart SDK and dart:math. It takes heavy inspiration from Guava (by Google) for Java, and ports some functions from it.

Classes

Note: https://pub.dev/documentation/starfruit/latest/starfruit/starfruit-library.html is auto-generated dartdocs. This has a more detailed rundown of every class and method. For here, every class and method is listed, along with basic usage for each class. You can also see usages below for extra guidance

StarMathUtils() OR mUtils

• To use, instantiate class with StarMathUtils() or use default instantiation (mUtils)
• Methods (mUtils.___):
  • roundToDouble (double input, int decimalPlaces)
  • ceilToDouble (double input, int decimalPlaces)
  • floorToDouble (double input, int decimalPlaces)
  • isPowerOfTwo (input)
  • log (base, input)
  • isMathematicalInteger (double input)
  • factorial (input)
  • fuzzyEquals (x, y, tolerance)
  • isPrime (int n)
  • lcm (x, y)
  • sinh (x)
  • cosh (x)
  • tanh (x)
  • asinh (x)
  • acosh (x)
  • atanh (x)
• Inputs are num unless otherwise stated

StarCollectionUtils() OR cUtils

• To use, instantiate class with StarCollectionsUtils() or use default instantiation (cUtils)
• Methods (cUtils.___):
  • chunks (List<Object> inp, int chunkSize)
  • collapse (List<List<Object>> inp)
  • nth (List<Object> inp, int interval)
  • random (List<Object> inp, [int n = 1])
  • flip (Map<Object, Object> inp)
  • zip (List<Object> keys, List<Object> values)
  • unzip (Map<Object,Object> inp)
  • every (List<Object> inp, bool test(Object element))

StarStats (dataset)

• To use, instantiate class with StarStats(List<num> a) and pass desired data as a paramater
• Getters:
  • baseSet
  • median
  • mean
  • mode
  • variance
  • stddev
  • cardinality
• Methods:
  • topElements (elements)
  • bottomElements (elements)
• Inputs are num

StarStatsXY (Map of points)

• To use, instantiate class with StarStatsXY(Map<num,num> xy) and pass desired data as parameter, where desired data is formatted {x1: y1, x2: y2, x3: y3, ...}
• Getters:
  • baseMap
  • x
  • y
  • linReg
  • corCoefficient
• Methods:
  • detCoefficient (int degree)

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Usage Examples

Math Utilities:

import 'package:starfruit/starfruit.dart';

main() {
  //Round to 2 decimal places
  //Ceiling and flooring to decimal places is also available
  print("Round 3.5634 to 2 decimal places:");
  print(mUtils.roundToDouble(3.5634, 2));
  print("");

  //Power of two check
  print("Is 8 a power of two?");
  print(mUtils.isPowerOfTwo(8));
  print("");

  //Calculate log base 2 of 8
  print("Calculate log base 2 of 8:");
  print(mUtils.log(2, 8));
  print("");

  //double isInteger check
  print("Is 6.0 an integer?");
  print(mUtils.isMathematicalInteger(6.0));
  print("");

  //Calculate 5!
  print("Calculate 5 factorial:");
  print(mUtils.factorial(5));
  print("");

  //Check if 2 is within 3 of 5
  print("Is 2 within 3 of 5?");
  print(mUtils.fuzzyEquals(2, 5, 3));
  print("");

  //Check if 7919 is a prime number
  print("Is 7919 prime?");
  print(mUtils.isPrime(7919));
  print("");

  //LCM of 2 and 7
  print("Calculate LCM of 2 and 7:");
  print(mUtils.lcm(2, 7));
  print("");

  //sinh of 1 radian
  print("Calculate sinh of 1 radian:");
  print(mUtils.sinh(1));
  print("");

  //mean of 3 and 7
  print("Calculate mean of 3 and 7:");
  print(mUtils.mean(3,7));
  print("");

  //nCr where n = 2 and r = 5
  print("Calculate the binomial coefficient of 2 and 5:");
  print(mUtils.combinationsOf(2, 5));
  print("");

  //nPr where n = 2 and r = 5
  print("Calculate the permutations of 2 and 5:");
  print(mUtils.permutationsOf(2, 5));
  print("");
}

Collection Utilities:

import 'package:starfruit/starfruit.dart';

main() {
  //Separate List into chunks
  print("Separate List into chunks of 4:");
  print(cUtils.chunks([1,2,3,4,5,6,7,8], 4));
  print("");

  //Collapse List<List<Object>> into just List<Object>
  print("Collapse List<List> into List:");
  print(cUtils.collapse( [[1,2,3],[4,5,6,7,8]] ));
  print("");

  //Get every nth object of list
  print("Get every 4th object:");
  print(cUtils.nth([1,2,3,4,5,6,7,8], 4));
  print("");

  //Get every n random elements of list
  print("Get 5 random elements:");
  print(cUtils.random([1,2,3,4,5,6,7,8], 5));
  print("");

  //Flip keys and values of a map
  print("Flip keys and values of a map:");
  print(cUtils.flip({1:0, 2:8, 3:4, 0:5}));
  print("");

  //Zip two Lists into a map
  print("Zip two lists into a map:");
  print(cUtils.zip([1,2,3,4], [5,6,7,8]));
  print("");

  //Unzip a map into two lists
  print("Unzip a map into two lists:");
  print(cUtils.unzip({0:1, 8:2, 4:3, 5:0}));
  print("");
}

Stats Utilities:

import 'package:starfruit/starfruit.dart';

main() {
  var stats = StarStats([1,3,4,5,12,3,4,67,8,0,22]);

  //median
  print("Calculate the median:");
  print(stats.median);
  print("");

  //mean
  print("Calculate the mean:");
  print(stats.mean);
  print("");

  //mode
  print("Calculate the mode:");
  print(stats.mode);
  print("");

  //variance
  print('Calculate the variance:');
  print(stats.variance);
  print("");

  //standard deviation
  print("Calculate the standard deviation:");
  print(stats.stdDev);
  print("");

  //cardinality; number of unique elements
  print("Calculate the cardinality:");
  print(stats.cardinality);
  print("");

  //7 greatest elements
  print("Return the 7 greatest elements:");
  print(stats.topElements(7));
  print("");
}

XY (Paired) Stats Utilities:

import 'package:starfruit/starfruit.dart';

main() {
  var xystats = StarStatsXY({2:3, 7:4, 4:6, 8:9, 1:2, 3:5, 11:14, 12:18});

  //Get correlation coefficient
  print("Calculate correlation coefficient:");
  print(xystats.corCoefficient);
  print("");

  //Get linear regression line
  print("Calculate linear regression line in form y = mx + b:");
  var lr = xystats.linearReg;
  print("y = ${lr[0]}x + ${lr[1]}");
  print("");

  //Get adjusted determination coefficient for linear regression line
  print("Calculate adj. determination coefficient for linear regression:");
  print(xystats.detCoefficient(1));
  print("");
}

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Features and bugs

Please file feature requests and bugs at the issue tracker.

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Starfruit, a set of Dart utility libraries.

©2019 Aditya Kishore

Licensed under the GNU LGPLv3 (See LICENSE)