From data to a map. Part one

Autorka omawia kolejne etapy przetwarzania i wizualizacji danych, które pokonuje kartograf opracowujący mapę, by dojść do form prezentacji. Rozważania w pierwszej części artykułu są oparte na zaproponowanym przez autorkę schemacie przejścia od danych do prezentacji kartograficznej. W drugiej części - z rozważań tych wyprowadzone zostaną poszczególne formy prezentacji kartograficznej.In contemporary cartography, computer has bacome a basic tool for map elaboration. Cartographic metodology is an important branch of cartography, into which computers have made a dynamic entrance. It lists basic rules of transformation and graphical presentation of data. This article attempts to look at the methods of cartographic presentation through the eyes of the map's editor and establish conditions, which have to be fulfilled to transform a set of data into a properly prepared map. "Cartographic presentation method" - meaning the process is differentiated from "cartographic presentation form" - meaning the result of this process, i.e. the map. The article follows the process of transition from data to cartographic presentation and establishes features, which allow a graphic picture to be called a cartographic presentation form. Data is the starting point of any cartographic presentation. in the process leading from data to presentation (fig.1) there are two separate stages: data preparation (transformation) and data visualization. At the stage of transformation the map editor can, according to the map's purpose, modify source data by changing measurement levels, data reference (point, linear, surface), its character (relative data, absolute data) and way of treating data (continuous, in intervals). Visualization is the next step from data to a cartographic presentation form. At this stage transformed data become a graphic picture. It happens after considering the following presentation elements: -graphical symbol, -visual variables, -graphical rendering, -correctly constructed legend. Correct and logical transfer from data through cartographic presentation method leads to a map. The effects of this transfer are graphic picture, i.e. cartographic presentation forms. Here it should be considered, if every set of data can be freely transformed and visualized and if such procedure would lead directly to a correct and aesy to use cartographic presentation form