Symbol and Chart Sizes

For many analyses, size properties for the display such as height, width or area can be set. Depending on the type of analysis, easymap offers the following options for selection:

Uniform or Fixed Size

When this option is selected, the user may define a common size for all charts or symbols. The size of the charts or symbols is then independent of the underlying data.

If, however, you wish the size of your charts or symbols to reflect the values of your data, please use one of the following options.

Classified

In this case, classes are generated for the data which is to determine size. Each class is assigned a particular size. This data-driven method for symbol-sizing usually results in more readable map displays, than when the size is proportional to data values. Example: You have a few major customers with up to 20 million € turnover per annum, but also many small customers with an annual turnover of less than 100.000€. The smallest of these has a turnover of 10.000€. With this range of values, it would be diffcult to find a suitable proportional factor beween turnover and symbol size. Classifying customers by turnover class, however, solves the problem: all customers with a turnover of less than 100.000€ are allocated a small symbol, those with a turnover of between 100.000€ and 5 million € a middle-sized and those with a turnover of over 5 million € a large symbol.

Size Proportional to Data

With this setting easymap converts the data values into the size of the diagrams or symbols using a portionality factor defined by the user. The user can choose between two types of size calculation.

Data-Driven Height/Width

The height or width of the diagrams or symbols is calculated in linear proportion to the data value. This can lead to very large scattering of the chart or symbol sizes. The cause can be easily explained by assuming that a circle is used as a symbol, because then the setting data value determines height/width causes a circle to become twice as "high" for a data value twice as large. But a circle with double diameter has four times the area! One should consider this and take into account that the eye unconsciously perceives the size of many forms rather by the area and less by the height or width.

Value specifies area

With this option, the area of a chart or symbol is calculated in linear proportion to the data value. Even when the data spans a wide statistical range, this does not usually lead to chart or symbol sizes greatly varying. Please refer to Data-Driven Height/Width to learn why this is the case.

Dynamic resizing of Data Change for a diagram or Symbol analysis

If you change the controlling data column(s) in a chart or symbol analysis, the new data values may lie in a completely different value range than before. This can lead to the fact that the proportionality factor used up to now is unsuitable for determining the size, because the charts or symbols are now all much too large or much too small. In such cases, it is therefore advisable to select under Dynamic sizing after data changes not to retain the proportionality factor but to retain the maximum size.

Resizing by Zoomautomatism

If the zoom automatic is activated, easymap is able to adjust the size of diagrams, symbols and other signatures also independently from the magnification scale. The following options are available:

  • Preserve scale: The zoom-in enlarges the objects in the same ratio as the map.
  • Slightly enlarge: The zoom-in enlarges objects to a lesser extent than the map.
  • Barely enlarge: The zoom-in enlarges the objects to a much smaller extent than the map.
  • Fixed size: Irrespective of the zoom of the map, the objects on the screen are always displayed with the same size.

The three variants of non-scaled magnification are used to set an "ideal" size independent of the map zoom. They are particularly useful if you work with the map mainly on screen and frequently change the map section. These setting options are also available for reports.

easymap offers these variants of size adjustment with automatic zoom for the following map contents:

  • All analyzes in which the user set sizes or data-dependent control (e.g., symbols, charts, lines or text)

  • Locations

  • Point Layers

  • Point geometries as base map (as shapefiles)