# R Language Definition

# Table of Contents

# Operators reference

`-` |
Minus, can be unary or binary |

`+` |
Plus, can be unary or binary |

`!` |
Unary not |

`~` |
Tilde, used for model formulae, can be either unary or binary |

`?` |
Help |

`:` |
Sequence, binary (in model formulae: interaction) |

`*` |
Multiplication, binary |

`/` |
Division, binary |

`^` |
Exponentiation, binary |

`%x%` |
Special binary operators, x can be replaced by any valid name |

`%%` |
Modulus, binary |

`%/%` |
Integer divide, binary |

`%*%` |
Matrix product, binary |

`%o%` |
Outer product, binary |

`%x%` |
Kronecker product, binary |

`%in%` |
Matching operator, binary (in model formulae: nesting) |

`<` |
Less than, binary |

`>` |
Greater than, binary |

`==` |
Equal to, binary |

`>=` |
Greater than or equal to, binary |

`<=` |
Less than or equal to, binary |

`&` |
And, binary, vectorized |

`&&` |
And, binary, not vectorized |

`|` |
Or, binary, vectorized |

`||` |
Or, binary, not vectorized |

`<-` |
Left assignment, binary |

`->` |
Right assignment, binary |

`$` |
List subset, binary |

# Quotes reference

```
[1] " " ":)" "a + b"
[1] "smile"
```

You can also create non-syntactic bindings using single and double quotes instead of backticks, but I don’t recommend it. The ability to

use strings on the left hand side of the assignment arrow is a historical artifact, used before R supported backticks.

# Assignment: `<-`

and `<<-`

reference

`<-`

always creates a variable in the current environment.`<<-`

never creates a variable in the current environment, but instead modifies an existing variable found by walking up the parent environments.- If
`<<-`

doesn’t find an existing variable, it will create one in the global environment.

# Access the value of last evaluated expression howto

- Use
`.Last.value`

```
[1] 10
[1] 10
```