Harold2017

Qt without Xcode

How to use Qt Creator for software development on macOS without having to install Xcode

Justification

Qt refuses to install on macOS unless Apple's Xcode is installed beforehand. This is unfortunate because:

Harold2017

// A simple quickref for Eigen. Add anything that's missing.
// Main author: Keir Mierle

#include <Eigen/Dense>

Matrix<double, 3, 3> A;               // Fixed rows and cols. Same as Matrix3d.
Matrix<double, 3, Dynamic> B;         // Fixed rows, dynamic cols.
Matrix<double, Dynamic, Dynamic> C;   // Full dynamic. Same as MatrixXd.
Matrix<double, 3, 3, RowMajor> E;     // Row major; default is column-major.
Matrix3f P, Q, R;                     // 3x3 float matrix.

Harold2017

template<class Vector3>
std::pair<Vector3, Vector3> best_plane_from_points(const std::vector<Vector3> & c)
{
	// copy coordinates to  matrix in Eigen format
	size_t num_atoms = c.size();
	Eigen::Matrix< Vector3::Scalar, Eigen::Dynamic, Eigen::Dynamic > coord(3, num_atoms);
	for (size_t i = 0; i < num_atoms; ++i) coord.col(i) = c[i];

	// calculate centroid
	Vector3 centroid(coord.row(0).mean(), coord.row(1).mean(), coord.row(2).mean());

Harold2017

BenchmarkMutexCache/10-8            10000000	       180 ns/op	       0 B/op	       0 allocs/op
BenchmarkMutexCache/100-8           10000000	       187 ns/op	       0 B/op	       0 allocs/op
BenchmarkMutexCache/1000-8          10000000	       214 ns/op	       0 B/op	       0 allocs/op
BenchmarkMutexCache/10000-8         10000000	       231 ns/op	       0 B/op	       0 allocs/op
BenchmarkMutexCache/100000-8         5000000	       254 ns/op	       2 B/op	       0 allocs/op
BenchmarkMutexCache/1000000-8        1000000	      1159 ns/op	     102 B/op	       1 allocs/op
BenchmarkMutexCache/10000000-8       1000000	      1481 ns/op	     184 B/op	       2 allocs/op
BenchmarkMutexCache/100000000-8      1000000	      1655 ns/op	     187 B/op	       3 allocs/op

BenchmarkSyncMapCache/10-8           5000000	       221 ns/op	       0 B/op	       0 allocs/op

Harold2017

Storing Images and Demos in your Repo

In this quick walkthough you'll learn how to create a separate branch in your repo to house your screenshots and demo gifs for use in your master's readme.

How to

1. Clone a fresh copy of your repo

In order to prevent any loss of work it is best to clone the repo in a separate location to complete this task.

2. Create a new branch

Create a new branch in your repo by using git checkout --orphan assets

Harold2017

#!/bin/bash
# This gist is a step by step instructions to build and install OpenCV from source on ubuntu 16.04 LTS
# note:  The easy and quick way to install is
# sudo pip3 install opencv-python
# sudo pip3 install opencv-contrib-python
# But this easy pypi installation can’t open video files on GNU/Linux distribution or on mac OS X system.
# And on some system opencv binaries provided packages are not compiled.
# Therefor we have no way rather than build it from source. 

Harold2017

How to add an image to a gist markdown

How to add an image to a gist

1. Create or find a gist that you own.
2. Clone your gist (replace <hash> with your gist's hash):

   # with ssh
   git clone [email protected]:<hash>.git mygist