A Simple Linear Algebra Package.
This package is intended to be a portable, easy to use linear algebra package. The library does not have any dependencies outside of Dart itself, thus making it portable and easy to integrate. Internally all numbers are stored as Dart Doubles ( 64 bit as specified in the IEEE 754 standard ).
Our goal is to keep the code readable, documented and maintainable.
Just a quick example on how to do matrix multiplication.
final Matrix a = Matrix([[1, 2], [3, 4]]);
final Vector b = Vector.column([2, 3]);
final Matrix e = Matrix([[8], [18]]);
Matrix result = a * b;
print(result);
print(result == e);
This prints
[[8.0], [18.0]]
true
A more extensive example with various matrix operations. See the Matrix API and Vector API for the full details.
import 'package:linalg/linalg.dart';
void example() {
// *****************************
// Lets solve a linear equation.
// *****************************
//
// A * B = E
//
// We have B and E, we have to find A.
//
// A * B * B' = E * B'
//
// Were B' = inverse of B.
//
// A * I = E * B'
//
// Where I = identity matrix
//
// A = E * B'
final Matrix B = Matrix([[2, 0], [1, 2]]);
final Matrix E = Matrix([[4, 4], [10, 8]]);
Matrix Bi = B.inverse();
Matrix A_calc = E * Bi;
final Matrix A = Matrix([[1, 2], [3, 4]]);
print("The calculated A_calc = $A_calc, the expected A is $A, they are ${A_calc==A?'':'not'} the same.");
// Expected: The calculated A = [[1.0, 2.0], [3.0, 4.0]], the expected A is [[1.0, 2.0], [3.0, 4.0]], they are the same.
// *****************************
// Lets do some more matrix math
// *****************************
//
// Next let multiply Matrix A by 3.
Matrix Am = A * 3.0;
print(Am);
// Expecting: [[3.0, 6.0], [9.0, 12.0]]
// Now add matrix B to A
Matrix AmPlusB = Am + B;
print(AmPlusB);
// Expecting: [[5.0, 6.0], [10.0, 14.0]]
// What is the determinant of the A matrix?
print("The determinant of A = ${A.det()}");
// Expecting The determinant of A = 2.0
}
Add linalg as a dependency to your flutter project.
dependencies:
linalg: ^0.3.2
and at the top of your dart file add:
import 'package:linalg/linalg.dart';
Original code came from: https://pub.dartlang.org/packages/toaster_linear
We ended up rewriting considerable parts of the code and adding tests and documentation.
example/example.dart
import 'package:linalg/linalg.dart';
void readMeExample() {
final Matrix a = Matrix([
[1, 2],
[3, 4]
]);
final Vector b = Vector.column([2, 3]);
final Matrix e = Matrix([
[8],
[18]
]);
Matrix result = a * b;
print(result);
print(result == e);
}
/// Example code for using the Matrix class.
void main() {
readMeExample();
// *****************************
// Lets solve a linear equation.
// *****************************
//
// A * B = E
//
// We have B and E, we have to find A.
//
// A * B * B' = E * B'
//
// Were B' = inverse of B.
//
// A * I = E * B'
//
// Where I = identity matrix
//
// A = E * B'
final Matrix B = Matrix([
[2.0, 0.0],
[1.0, 2.0]
]);
final Matrix E = Matrix([
[4.0, 4.0],
[10.0, 8.0]
]);
Matrix Bi = B.inverse();
Matrix A_calc = E * Bi;
final Matrix A = Matrix([
[1.0, 2.0],
[3.0, 4.0]
]);
print(
"The calculated A = $A_calc, the expected A is $A, they are ${A_calc == A ? '' : 'not'} the same.");
// Expected: The calculated A = [[1.0, 2.0], [3.0, 4.0]], the expected A is [[1.0, 2.0], [3.0, 4.0]], they are the same.
// *****************************
// Lets do some more matrix math
// *****************************
//
// Next let multiply Matrix A by 3.
Matrix Am = A * 3.0;
print(Am);
// Expecting: [[3.0, 6.0], [9.0, 12.0]]
// Now add matrix B to A
Matrix AmPlusB = Am + B;
print(AmPlusB);
// Expecting: [[5.0, 6.0], [10.0, 14.0]]
// What is the determinant of the A matrix?
print("The determinant of A = ${A.det()}");
// Expecting The determinant of A = 2.0
}
Add this to your package's pubspec.yaml file:
dependencies:
linalg: ^0.3.2
You can install packages from the command line:
with pub:
$ pub get
with Flutter:
$ flutter pub get
Alternatively, your editor might support pub get
or flutter pub get
.
Check the docs for your editor to learn more.
Now in your Dart code, you can use:
import 'package:linalg/linalg.dart';
Popularity:
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60

Health:
Code health derived from static analysis.
[more]

99

Maintenance:
Reflects how tidy and uptodate the package is.
[more]

100

Overall:
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[more]

80

We analyzed this package on Aug 20, 2019, and provided a score, details, and suggestions below. Analysis was completed with status completed using:
Detected platforms: Flutter, web, other
No platform restriction found in primary library
package:linalg/linalg.dart
.
Fix lib/matrix.dart
. (1.49 points)
Analysis of lib/matrix.dart
reported 3 hints:
line 151 col 7: DO use curly braces for all flow control structures.
line 159 col 7: DO use curly braces for all flow control structures.
line 174 col 7: DO use curly braces for all flow control structures.
Package  Constraint  Resolved  Available 

Direct dependencies  
Dart SDK  >=2.0.0 <3.0.0  
Dev dependencies  
coverage  ^0.12.3  
grinder  ^0.8.3  
grinder_coveralls  ^0.2.0  
test  ^1.5.0 