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C++ Notes

C++ 11 features

* bind function

Mixing bound and call arguments with placeholders

• Example

#include <functional>
using namespace std;
using namespace std::placeholders; // needed for _1, _2, etc
int sum3(int a, int b, int c)

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// Use Gists to store code you would like to remember later on
console.log(window); // log the "window" object to the console

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#JAVA Notes

Chap. Access Control and Code Organization

• Library Unit: package
• Compilation Unit: .java src files
  • each src file should have only ONE public class and all else are supporting classes with package access
• a package statement: package [package_name];

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Comparative study of programming paradigms

Overview

Procedural programming is the most primitive programming paradigm. It treats compuation as a set of sequential steps. It packages a set of repeatable steps in functions that takes input arguments. The most popular language for procedural programming is C. It iterative and sequential and has little overhead therefore high execution speed and small size. It is often used to optimize the performance of a certain portion of code. But it doesn't scale well with large systems and becomes hard to maintain as the software grows.

Object-oriented programming (OOP) stands for a programming paradigm that are marked by 'objects' that encapsulate data fields and behaviors ('methods'). It also imposes access control on class members to keep users from tampering with internals of a class. Hence it has better safety and decomposition.OOP works by interaction between objects. It also enables inheritance and polymorphism. Inheritance means that a class can derive from

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String/ Text

Filter a string for a set of chars

import string
# Make a reusable string of all characters, which does double duty
# as a translation table specifying "no translation whatsoever"
allchars = string.maketrans('', '')
def makefilter(keep):
""" Return a function that takes a string and returns a partial copy

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#Basics

writing output with no \n at the end echo -n 'something with no newline'

redirecting stdout and stderr to the same file

both >& outfile

A hyphen indicates that input is taken from the keyboard. In this example, to create a new file file2 that consists of text typed in from the keyboard followed by the contents of file1

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#Start-out Booleans: &&, ||, not , ==, /=(not equal)

Basic functions(prefix or use `` for infix):

succ 8 returns 9

Function syntax

functions can't begin with uppercase letters.

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Fundamentals

Gray Code

Binary2Gray conversion

unsigned int binary2gray(unsigned int bi){
return bi ^ (bi>>1) ;
}

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```python
#!/usr/bin/python

import requests as rq 
import bs4 
import logging 
logging.basicConfig(filename="epsgCrawl.log",level=logging.WARNING, format="%(levelname)s::%(message)s")

class EPSGLookup(object):
    """docstring for EPSGLookup"""

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Setting up and starting

• Create a new local repo: git init
• Clone a repo from github git clone [URL]

##Basic Snapshotting

check status: git status -s (-s is for short)

use git diff

1. git diff shows the patch (unstaged changes since last commit)