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