====== Get Map Value ======

===== Description =====

Retrieves the value of a map cell at a specified line and column.

===== Inputs =====

^ Name  ^ Type  ^ Description  ^
| Map  | [[Map Type]]  | Map the value is retrieved from.  |
| Cell Line  | [[Positive Integer Value Type]]  | Line of the cell. Line 1 is the topmost line.  |
| Cell Column  | [[Positive Integer Value Type]]  | Column of the cell. Column 1 is the leftmost column.  |

===== Optional Inputs =====

^ Name  ^ Type  ^ Description  ^ Default Value  ^
| Value If Null  | [[Real Value Type]]  | Value returned when the cell at the specified coordinates equals Map's null value. This is an advanced port.  | 0.0  |

===== Outputs =====

^ Name  ^ Type  ^ Description  ^
| Cell Value  | [[Real Value Type]]  | Retrieved cell value.  |

===== Group =====

[[Functor List#Map Algebra | Map Algebra]]

===== Notes =====

Raises an error if Cell Line or Cell Column falls outside the dimensions of Map.

===== Internal Name =====

GetMapValue