Statistics and Statistical Programming (Winter 2017)/R lecture outline: Week 1

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Lecture Outline

  • using R as a calculator:
    • addition: 2 + 2
    • subtraction: 2 - 3
    • multiplication: 5 * 4
    • division: 5/2
    • more complicated stuff: use parentheses!
    • powers: 2^2; 2^3
  • variables
    • the basic concept and how they work
    • syntax for assignment: use <- (although = equals too, it's not idiomatic R)
    • what makes a valid variables name: starts with a letter, contains letters and numbers; case is important; instead of spaces, use "." (not _ as in Python, although _ will usually work too)
    • saving numbers to variables: cups.of.flour <- 2
    • special variables built in: pi (we'll see many more)
  • types of variables
    • numeric: we've already seen, with or without the decimal point
    • character: name <- "mako" (uses single or double quotes)
    • logical: TRUE or FALSE (all caps)
  • functions: contains parens right after the variable name
    • there are many built in functions including:
      • sqrt()
      • log()
      • log1p() — super useful!
      • check your reference card for many, many more