spire

Pros of Breeze

• More comprehensive library for numerical computing and scientific computing
• Better support for linear algebra operations and matrix manipulations
• Includes machine learning algorithms and statistical functions

Cons of Breeze

• Steeper learning curve due to its broader scope
• Potentially slower compilation times for large projects
• Less focus on type safety compared to Spire

Code Comparison

Breeze example:

import breeze.linalg._
import breeze.numerics._

val x = DenseVector(1.0, 2.0, 3.0)
val y = DenseVector(4.0, 5.0, 6.0)
val result = x dot y

Spire example:

import spire.math._
import spire.implicits._

val x = Vec(1.0, 2.0, 3.0)
val y = Vec(4.0, 5.0, 6.0)
val result = x dot y

Both libraries provide similar functionality for basic vector operations, but Breeze offers more advanced features for scientific computing and machine learning tasks. Spire, on the other hand, focuses more on providing a type-safe and efficient foundation for numeric operations in Scala.

Pros of Spire

• More comprehensive and feature-rich library for numeric types and operations
• Better performance optimizations for numeric computations
• Wider range of supported numeric types and algebraic structures

Cons of Spire

• Larger codebase and potentially steeper learning curve
• May include more functionality than needed for simpler projects
• Potentially higher compilation times due to its extensive type-level programming

Code Comparison

Spire:

import spire.math._
import spire.implicits._

val result = Complex(1, 2) * Complex(3, 4)

Spire>:

import spire.math._
import spire.implicits._

val result = Complex(1, 2) * Complex(3, 4)

In this case, the code comparison shows identical usage for basic complex number operations, as both libraries provide similar core functionality. The main differences lie in the breadth of features and performance optimizations that Spire offers beyond these basic operations.

Pros of scala3

• Comprehensive language implementation with full compiler and runtime
• Introduces significant new features like union types and contextual abstractions
• Larger community and more widespread adoption in industry

Cons of scala3

• Steeper learning curve due to more complex language features
• Potentially slower compilation times for large projects
• Less focused on specific numeric/algebraic operations

Code Comparison

scala3 (new syntax for type classes):

trait Semigroup[T]:
  def combine(x: T, y: T): T

given Semigroup[Int] with
  def combine(x: Int, y: Int): Int = x + y

Spire (numeric type class):

import spire.algebra._
import spire.implicits._

def sum[A: Semiring](as: Seq[A]): A = as.foldLeft(Semiring[A].zero)(_ + _)

Key Differences

• Spire focuses on numeric and algebraic abstractions, while scala3 is a full language implementation
• scala3 introduces new syntax and features, whereas Spire works within existing Scala 2.x constraints
• Spire provides specialized implementations for performance, while scala3 offers more general language improvements

Use Cases

• Choose scala3 for general Scala development and to leverage new language features
• Opt for Spire when working on projects requiring advanced numeric computations or algebraic abstractions

Pros of Shapeless

• More general-purpose, offering generic programming capabilities across various domains
• Provides powerful type-level programming features like heterogeneous lists and generic representations
• Extensive support for type-class derivation and automatic instance generation

Cons of Shapeless

• Steeper learning curve due to its advanced type-level concepts
• Can lead to longer compilation times, especially for complex generic derivations
• May introduce additional complexity in codebases where its full power is not needed

Code Comparison

Shapeless example (type-safe heterogeneous list):

import shapeless._

val hlist = 1 :: "hello" :: true :: HNil
val first: Int = hlist.head
val rest: String :: Boolean :: HNil = hlist.tail

Spire example (numeric operations):

import spire.math._
import spire.implicits._

val result = Complex(1, 2) + Complex(3, 4)
val norm = result.abs

Summary

Shapeless excels in generic programming and type-level computations, offering powerful abstractions for advanced Scala developers. Spire, on the other hand, focuses on providing efficient numeric types and operations, making it more suitable for mathematical and scientific computing tasks. While Shapeless offers greater flexibility, Spire provides specialized functionality for numeric operations with better performance in its domain.