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Autonomous Systems Interview Preparations

This document contains some interview questions as provided in Udacity's Robotics Engineer Nanodegree program.

Project Instructions

Role Selection

It's time for you to practice your interviewing skills! Over the next several pages, you'll see that we have specific roles in Autonomous Systems, just like the videos you watched before:

LIST OF MAT TYPE IN OPENCV

from http://ninghang.blogspot.com.es/2012/11/list-of-mat-type-in-opencv.html

credit to: https://www.blogger.com/profile/03087225378863523119

A Mapping of Type to Numbers in OpenCV

	C1	C2	C3	C4
CV_8U	0	8	16	24
CV_8S	1	9	17	25

Generic 1,2,3 Noise

float rand(float n){return fract(sin(n) * 43758.5453123);}

float noise(float p){
	float fl = floor(p);
  float fc = fract(p);
	return mix(rand(fl), rand(fl + 1.0), fc);
}

$ git checkout --orphan NEWBRANCH
$ git rm -rf .

--orphan creates a new branch, but it starts without any commit. After running the above command you are on a new branch "NEWBRANCH", and the first commit you create from this state will start a new history without any ancestry.

You can then start adding files and commit them and they will live in their own branch. If you take a look at the log, you will see that it is isolated from the original log.

	#include <iostream>
	#include <fstream>
	#include <unistd.h>

	void process_mem_usage(double& vm_usage, double& resident_set)
	{
	vm_usage = 0.0;
	resident_set = 0.0;

	// the two fields we want

	cv::Mat img = cv::imread("img.png");
	GLuint tex_in;
	glGenTextures(1, &tex_in);
	glBindTexture(GL_TEXTURE_2D, tex_in);

	/*By practice, the internalParam:
	* GL_RGB, GL_RGBA, GL_RGB8, GL_RGBA8 work
	* GL_RGB8UI, GL_RGBA8UI don't work
	*/
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, img.cols, img.rows, 0, GL_BGR, GL_UNSIGNED_BYTE, img.data); // copy data to texture object

	/*
	* Minimal Linux- and GLX-specific example of using a pool of Pixel Buffer
	* Objects to stream pixel data.
	*
	* This is a minimal test case for opening an OpenGL window with raw
	* X11/Xlib/GLX, drawing a simple test image, and fast PBO-based streaming of
	* image data to disk with glReadPixels().
	*
	* On an NVidia RTX2080 Super, on Ubuntu 20.04, saving to an SSD, this sustains
	* 150+fps (peaking at 500+, hitting 900+ if only writing a single file instead

	// Sobel Edge Detection Filter
	// GLSL Fragment Shader
	// Implementation by Patrick Hebron

	uniform sampler2D texture;
	uniform float width;
	uniform float height;

	void make_kernel(inout vec4 n[9], sampler2D tex, vec2 coord)
	{

	# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
	# file Copyright.txt or https://cmake.org/licensing for details.

	#.rst:
	# FindOpenMP
	# ----------
	#
	# Finds OpenMP support
	#
	# This module can be used to detect OpenMP support in a compiler. If

	/* Small example of using bicubic interpolation in ceres with autodiff */
	#include <ceres/ceres.h>
	#include <ceres/cubic_interpolation.h>

	#include <cassert>

	using Grid = ceres::Grid2D<double>;
	using Interpolator = ceres::BiCubicInterpolator<Grid>;

	struct Residual {