Tanaka method or how to make shaded contour lines

Contour lines have become a commonplace, unassuming companion of our cartographic outputs - GIS has made us forget their visual potential. Already in the 19th century cartographers experimented with shaded contours, but the technique has become known as the Tanaka method, after Japanese cartographer Kitiro Tanaka (Kennelly 2016, wiki.gis 2017). Even the cover page of … Continue reading Tanaka method or how to make shaded contour lines

My first QGIS map: the aid from Cyrene

Cyrene, Lybia Sometime during the reign of Alexander of Macedon a famine broke out in Greece. We don't have many documents reporting the gravity of situation; apparently Greece was suffering much during the tumultuous years just before and after the Macedonian conquest. The prosperous city of Cyrene, on the coast of today's Libya, came to … Continue reading My first QGIS map: the aid from Cyrene

Polar (circular) diagram

Orientation of geographic features can be an important piece of information, for instance when studying ancient field systems or analysing geological formations. The problem comes when we try to summarise such data graphically . Standard histograms are not ideal because they cut through the continuous distribution - one cannot easily understand the relationship between the … Continue reading Polar (circular) diagram

SIG collaboratif, solution simple et gratuite

Travailler, ce n’est peut-être pas toujours la chose la plus passionnante, mais c’est quand même plus amusant (et plus efficace) en collaboration. Il y a, dans le monde du SIG, bien de solutions pour le travail collaboratif sur un même jeu de données, mais le plus souvent elles sont coûteuses ou exigeantes au niveau technique. … Continue reading SIG collaboratif, solution simple et gratuite