University:
Boston University
Course:
MET CS 201 | Introduction to Programming
Academic year:

2023
Views:

495

Pages:

10
Author:

scoobie897rtf

Introduction to C++: Part 1 Getting started with the room B27 terminals  Log on with your BU username  On the desktop is a Training Files folder. Open it and go to the subfolder: RCS_Tutorials\Tutorial Files\Introduction to C++  Copy the CodeBlocks Projects folder to your desktop. Getting started on the SCC  If you prefer to work on the SCC and have your own account, login using your account to the host scc2.bu.edu  On the room terminals there is a MobaXterm link on the desktop  Load the codeblocks module: module module module module module load load load load load gcc/5.3.0 hunspell/1.4.1 wxwidgets/2.8.12 gdb/7.11.1 codeblocks  Make a folder in your home directory and copy in the files: mkdir cpp_tutorial && cd !$ unzip /scratch/intro_to_cpp_tutorial_0.1.zip Tutorial Outline: Part 1         Very brief history of C++ Definition object-oriented programming When C++ is a good choice The Code::Blocks IDE Object-oriented concepts First program! Some C++ syntax Polymorphism Very brief history of C++ C C++ Object-oriented programming  Programming has many paradigms, or styles, which are used when writing programs.  Wikipedia lists >40!: class GasMolecule • • Data: • molecular weight, structure, common names, etc. Methods: • IR(wavenumStart, wavenumEnd) : return IR emission spectrum in range https://en.wikipedia.org/wiki/Programming_paradigm  Procedural (C, Fortran, Matlab)  Dataflow (Simulink, VHDL, Labview)  Functional (Excel, Lisp, F#)  Object-oriented programming (OOP):  Seeks to define a program in terms of the things in the problem (files, molecules, buildings, cars, people, etc.) and what they need and can do. Objects (instances of a class) GasMolecule ch4 GasMolecule co2 spectrum = ch4.IR(1000,3500) Name = co2.common_name “pseudo-code” Object-oriented programming     OOP defines classes to represent these things. Classes can contain data and methods (internal functions). Classes control access to internal data and methods. A public interface is used by external code when using the class. This is a highly effective way of modeling real world problems inside of a computer program. “Class Car” public interface private data and methods C++ Compared to Some Other Languages C++ Python Fortran Language Type compiled interpreted compiled Variable type style Strong Strong Strong Variable Safety unsafe safe mostly safe Type checking At compilation and at run-time Run-time Compilation Paradigms OO, procedural, functional, generic, dataflow, and others OO, procedural, functional Procedural C compatibility Nearly 100% Not directly Call C libraries, with many pitfalls Relative speed Fast Slow Fast “Actually I made up the term ‘object-oriented’, and I can tell you I did not have C++ in mind.” – Alan Kay (helped invent OO programming, the Smalltalk language, and the GUI) When to choose C++  Despite its many competitors C++ has remained popular for ~30 years and will continue to be so in the foreseeable future.  Why?  Complex problems and programs can be effectively implemented  OOP works in the real world!  No other language quite matches C++’s combination of performance, expressiveness, and ability to handle complex programs. “If you’re not at all interested in performance, shouldn’t you be in the Python room down the hall?” ― Scott Meyers (author of Effective Modern C++)  Choose C++ when:  Program performance matters  Dealing with large amounts of data, multiple CPUs, complex algorithms, etc.  Programmer productivity is less important  It is faster to produce working code in Python, R, Matlab or other scripting languages!  The programming language itself can help organize your code  Not everything is a vector or matrix, right Matlab?  Access to libraries that will help with your problem  Ex. Nvidia’s CUDA Thrust library for GPUs  Your group uses it already! Pros/Cons of C++ Pros Cons  Enormous number of available libraries  Flexibility for programmers  A very large language - this tutorial won’t even attempt to describe all of it.  High (objects) and low (fiddling with memory) level styles are supported  And your instructor makes no claim to know the entire language!  No automatic memory management  No automatic memory management  You are in control of memory usage  You are in control of memory usage  Compiled  Strong type system  High performance  Includes all the subtleties of C and adds its own  Generally requires careful attention to detail! “C++: an octopus made by nailing extra legs onto a dog.” – Steve Taylor