| // Fuzzy string-matching algorithm | |
| // Implementation of algorithm described at: http://blog.notdot.net/2007/4/Damn-Cool-Algorithms-Part-1-BK-Trees | |
| // Essentially builds an index of strings by levenshtein distance (N-ary tree) on which you can run range queries. | |
| // The root node can be chosen arbitrarily. Each node holds a string and a collection of edges, representing distance to other strings, which then have their own children and so on, building a complete index. | |
| // See https://github.com/vy/bk-tree for (impressive) performance statistics despite this tending to create an unbalanced N-ary tree | |
| class BKTreeNode { | |
| var value: String | |
| var edges: Dictionary<Int, BKTreeNode> |
| defaults write xcodebuild PBXNumberOfParallelBuildSubtasks 4 | |
| defaults write xcodebuild IDEBuildOperationMaxNumberOfConcurrentCompileTasks 4 | |
| defaults write com.apple.xcode PBXNumberOfParallelBuildSubtasks 4 | |
| defaults write com.apple.xcode IDEBuildOperationMaxNumberOfConcurrentCompileTasks 4 |
Picking the right architecture = Picking the right battles + Managing trade-offs
| import Foundation | |
| protocol Monoid { | |
| static var zero: Self { get } | |
| func appending(_: Self) -> Self | |
| } | |
| struct AnyMonoid<Type> { | |
| var zero: Type | |
| let append: (Type, Type) -> Type |
The repository for the assignment is public and Github does not allow the creation of private forks for public repositories.
The correct way of creating a private frok by duplicating the repo is documented here.
For this assignment the commands are:
git clone --bare [email protected]:usi-systems/easytrace.git
The libdispatch is one of the most misused API due to the way it was presented to us when it was introduced and for many years after that, and due to the confusing documentation and API. This page is a compilation of important things to know if you're going to use this library. Many references are available at the end of this document pointing to comments from Apple's very own libdispatch maintainer (Pierre Habouzit).
My take-aways are:
You should create very few, long-lived, well-defined queues. These queues should be seen as execution contexts in your program (gui, background work, ...) that benefit from executing in parallel. An important thing to note is that if these queues are all active at once, you will get as many threads running. In most apps, you probably do not need to create more than 3 or 4 queues.
Go serial first, and as you find performance bottle necks, measure why, and if concurrency helps, apply with care, always validating under system pressure. Reuse
| // test in playground targeting iOS | |
| import UIKit | |
| import QuartzCore | |
| let sRGBSpace = CGColorSpace(name: CGColorSpace.sRGB)! | |
| let linearSpace = CGColorSpace(name: CGColorSpace.linearSRGB)! | |
| func dumpImageFirstPixel(_ image: UIImage) { | |
| guard let cgImage = image.cgImage, | |
| let dataBuffer = cgImage.dataProvider?.data as Data?, |
This document is a guide to writing agile contracts. Unlike traditional contracts, an agile contract does not specify individual tasks to be completed by the Contractor. Rather, an agile contract specifies how the Client and Contractor interact, and how the Contractor is paid. The Deliverable Work performed for the contract is determined through an ongoing collaboration between the Client and the Contractor.
Agile contracts require a great deal of trust from both the Client and the Contractor. This trust is fostered through tight feedback cycles and well-defined responsibilities that both parties can expect from each other. More so than traditional contracts, an agile contract requires active participation from the Client.
