Geoclip - web-mapping - thematic maps




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Features > Multiple themes
To each data type its appropriate display mode

The various display modes offered by Geoclip are based on standard cartographic representation rules. Geoclip strives at creating precise, clear, and attractive maps.

Geoclip creates thematic maps. To achieve this, it offers various display modes depending on which data are to be viewed. The three following “basic” modes are offered :

Proportional symbols

Graduated color

“Hedgehog” plots

Displayed data type :
absolute values

e.g.: population, number of facilities, and so on.
The symbol used is a circle, the simplest and clearest geometric shape ; the circle’s area is proportional to the represented data.

Displayed data type :
relative values

e.g.: population density, evolution rate, and so on.
These maps are called "choropleth" maps ; variables need to be made "discrete", i.e. thresholds have to be determined to separate each bracket.

Displayed data type :
flow data

e.g.: major urban centres
Each geographic unit is connected by a line to another geographic unit (pole) ; the stronger the flows, the clearer the map, because fewer lines will cross each other.

Combined representations
Some of these display modes can be combined for two-level viewing – foreground and background, the bracket view is always in the background. A special combination can be made using brackets and proportional circles: the circles can be filled with colours corresponding to the various brackets.

Clearer displays using smoothing
The clarity of some maps that use brackets can be improved by smoothing the values, which reduces the disparity between the values of nearby geographic units. This is done by replacing the value of each unit by the mean value between its own and that of other nearby geographic units.

Basic displays
The simplest display mode aims only at locating objects inside an area. This is successfully accomplished by most of the maps we use to travel. In thematic cartography, this display mode allows you to locate buildings and facilities using a fixed-size symbol. These symbols can use different colours and/or shapes to distinguish categories.

This example is taken from telemedicine maps (Cartographie de la Télémédecine, see Recent production). This interactive atlas enables uses to locate operational telehealth networks in each French region