| import cv2 | |
| import time | |
| import math | |
| import numpy as np | |
| import tensorflow as tf | |
| class SsdAnchorsCalculatorOptions: | |
| def __init__(self, input_size_width, input_size_height, min_scale, max_scale | |
| , num_layers, feature_map_width, feature_map_height | |
| , strides, aspect_ratios, anchor_offset_x=0.5, anchor_offset_y=0.5 |
| sudo add-apt-repository -y ppa:apt-fast/stable | |
| sudo add-apt-repository -y ppa:graphics-drivers/ppa | |
| sudo apt-get update | |
| sudo apt-get -y install apt-fast | |
| # prompts | |
| sudo apt-fast -y upgrade | |
| sudo apt-fast install -y python3-pip ubuntu-drivers-common libvorbis-dev libflac-dev libsndfile-dev cmake build-essential libgflags-dev libgoogle-glog-dev libgtest-dev google-mock zlib1g-dev libeigen3-dev libboost-all-dev libasound2-dev libogg-dev libtool libfftw3-dev libbz2-dev liblzma-dev libgoogle-glog0v5 gcc-6 gfortran-6 g++-6 doxygen graphviz libsox-fmt-all parallel exuberant-ctags vim-nox python-powerline python3-pip ack lsyncd | |
| sudo apt-fast install -y tigervnc-standalone-server firefox mesa-common-dev |
Check out this tutorial demonstrating Python interoperability in Swift.
PythonLibrary.useVersionThis function is intended to set the Python version before any references to the global PythonInterface called Python -
it cannot be used to switch Python versions dynamically.
| // | |
| // main.swift | |
| // OptionParser | |
| // | |
| // Created by Chris Eidhof on 28.02.19. | |
| // Copyright © 2019 objc.io. All rights reserved. | |
| // | |
| import Foundation |
A quadratic space is a real vector space V with a quadratic form Q(x), e.g. V = R^n with Q as the squared length. The Clifford algebra Cl(V) of a quadratic space is the associative algebra that contains V and satisfies x^2 = Q(x) for all x in V. We're imposing by fiat that the square of a vector should be the quadratic form's value and seeing where it takes us. Treat x^2 = Q(x) as a symbolic rewriting rule that lets you replace x^2 or x x with Q(x) and vice versa whenever x is a vector. Beyond that Cl(V) satisfies the standard axioms of an algebra: it lets you multiply by scalars, it's associative and distributive, but not necessarily commutative.
Remarkably, this is all you need to derive everything about Clifford algebras.
Let me show you how easy it is to bootstrap the theory from nothing.
We know Cl(V) contains a copy of V. Since x^2 = Q(x) for all x, it must also contain a copy of some nonnegative reals.
| #!/usr/bin/swift sh | |
| import Foundation | |
| import PromiseKit // @mxcl ~> 6.5 | |
| import Swifter // @mattdonnelly == b27a89 | |
| let swifter = Swifter( | |
| consumerKey: "FILL", | |
| consumerSecret: "ME", | |
| oauthToken: "IN", | |
| oauthTokenSecret: "https://developer.twitter.com/en/docs/basics/apps/overview.html" |
When VPNs Just Work™, they're a fantastic way of allowing access to a private network from remote locations. When they don't work it can be an experience in frustration. I've had situations where I can connect to a VPN from my Mac, but various networking situations cause routing conflicts. Here are a couple of cases and how I've been able to get around them.
In this example the VPN we are connecting to has a subnet that does not conflict with our local IP, but has additional routes that conflict in some way with our local network's routing. In my example the remote subnet is 10.0.x.0/24, my local subnet is 10.0.y.0/24, and the conflicting route is 10.0.0.0/8. Without the later route, I can't access all hosts on the VPN without manually adding the route after connecting to the VPN:
| import Darwin | |
| @dynamicMemberLookup | |
| struct Environment { | |
| subscript(dynamicMember name: String) -> String? { | |
| get { | |
| guard let value = getenv(name) else { return nil } | |
| return String(validatingUTF8: value) | |
| } |
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