Building a zone of flood by marks of a water level

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This mode allows to construct a zone of flood by marks of a water level.

Marks of a water level should be provided by data of a relief's heights matrix (MTW).

The marks which have been not provided by data of a matrix of heights are excluded from processing.

Result of construction is the matrix of qualities (MTQ), containing values of depths of a flood zone. The size of an element of a resulting matrix of qualities in meters on district is defined by the most exact matrix of heights (MTW).

According to marks of a level the surface of water is built, then this surface will compare to a surface of  relief's district. If the surface of water in a point of district is located above a surface of a relief, then the value of depth of flood in the given point will be placed into a resulting matrix of qualities.

Coordinates of marks and value of a water level are set in meters in system of coordinates of a vector map.

Values of level can be set by sizes of exceeding concerning a surface of relief (the mode Absolute marks of level is not set) or by values of absolute heights of level (the mode Absolute marks of level is set).

Marks of a water level can be set:

- in a textual file,

- in a data base,

- by selected point objects of a map.

 

If marks of a level are contained in a textual file (Data format - Textual file), then one line of a textual file corresponds to one mark. A format of a line (« X Y H », «№ X Y H ») and the divider of fields can be set in String type group.

If marks of a level are contained in a data base (Data format - Data base) at a choice of DBF-file it is necessary to execute adjustment of conformity of marks coordinates and fields of base in Selecting of fields from data base dialog.

If marks of a level are presented by the selected point objects of a map (Data format - Selected objects), then the metrics of these objects should contain H coordinate (value of a water level) and an attribute: Height concerning a surface.

The specified marks of a water level are displayed in a window of dialog. If marks are contained in a textual file or in a database the coordinates of marks and the value of a level can be edited.

The sizes of a site of district, for which the zone of flood is created, are defined by coordinates of the specified marks. If it is required to expand a site of a zone of flood, it is necessary to set value in a window: Increase of zone size.

In Minimum window it is possible to set the lower threshold value of depths for a zone of flood. For example, if user is interested in the depths more than one meter he should set in Minimal window the value « 1.0». Then depths smaller than one meter into a resulting matrix of qualities will not be placed.