Some languages are 'compiled' and some are 'interpreted'

• Compiled languages are converted directly into machine code with a compiler that the processor can execute.
  • Fortran, C, C++
• Interpreters will run through a program line by line and execute each command.
  • Python, JavaScript, Ruby

Say "Hello World" in 4 different languages

Fortran

       program hello

          print *, "Hello World!"

       end program hello

C

#include <stdio.h>

int main()

{

   printf("Hello, World!");

   return 0;

}

C++

#include <iostream>

using namespace std;

int main() 

{

    cout << "Hello, World!";

    return 0;

}

Python

print("Hello, World!")

Scientific Computing

• Start with a simple model (equations)
  • Program & validate to see if it describes the physical system
• Improve the model (add more physics & features)
  • Program & validate to see if it describes the physical system
  • Rinse & Repeat

Let's really program!

We will use Trinket, an online Python interactive development environment (IDE)

We will program in Python2 and Python3. Huh?

• Languages change over time - new features are added, old features removed to make programming easier or more powerful