# Programming Syntax

Syntax is the way a command can be written and a description of what is allowed and what is not allowed.

Here I will use the standard syntax layout unless I have a good reason to do otherwise with italics indicating something that the user customizes and square bracket indicating something that is optional. For instance the PHP if command syntax:

if (*test*) {
[*statements*;]
}

indicates that you start by typing `if (`

. Then you type whatever condition you want to be evaluated. Then you type `) {`

then it is optional to place one or more statements here. Then you finish the if statement with a `}`

.

### Here is a table of common PHP commands:

addition | `$x+$y` |

subtraction | `$x-$y` |

multiplication | `$x*$y` |

division | `$x/$y` |

modulus | `$x%$y` |

exponentiation | `pow($x,$y)` |

absolute value | `abs($x)` |

round up | `ceil($x)` |

round down | `floor($x)` |

round to digits | `round($x[, $digits]` |

cosine | `cos($x)` |

sine | `sin($x)` |

tangent | `tan($x)` |

logarithm | `log($x[, $base])` |

minimum | `min($x[,$y,...])` |

maximum | `max($x[,$y,...])` |

random number | `rand([$min,$max])` |

square root | `sqrt($x)` |

if statement | `if (` |

print statement | `print ` |

variables | `$x=` |

arrays (brackets are literal) | `$i[` |

strings | `"string" or 'string'` |

There are many more PHP commands. Many books have been written about PHP and the on-line documentation is very good and includes all the commands.