Operation Manual

Mapping
Mapping concepts
15
Crystal Reports User’s Guide 301
Map types
The Map Expert also provides five basic map types, each suitable for a
different strategy of data analysis. When deciding which map type best fits
your report, you should consider the type of data you want to analyze. For
example, if you want the map to display one data item for each geographic
division (city, state, country, and so on), then you might use a Ranged, Dot
Density, or Graduated map. On the other hand, if you want the map to display
more than one value for each new geographic division, then you could use a
Pie Chart map or a Bar Chart map. The following is an overview of the main
map types and their most common uses.
Ranged
A Ranged map breaks the data into ranges, assigns a specific color to each
range, then color codes each geographic area on the map to display the
range. For example, you could create a map that displays Last Year’s Sales by
Region. If you have sales ranging from zero to 100,000, you might give the
map five ranges, with equal intervals of 20,000 each. You could use shades of
red (going from dark to light red) to color code each region according to those
sales figures. Then you could use this map to see where sales are the highest.
With equal intervals, you might end up with all your regions ranging between
zero and 20,000, except perhaps one region (for example, California) that
might have exceptionally high sales (such as 98,000). This map would be a
very distorted representation of the data. A more useful map would have
ranges like 0-5000, 5000-10000, 10000-15000, 15000-20000, and over
20000. It is important to carefully define your ranges.
Note: The end value for each division is repeated as the start value for the
next division; the actual value is included in the group it starts. That is, the
ranges in the previous example are actually: 0-4999, 5000-9999, and so on.
There are four different distribution methods for ranged maps.
• Equal count
This option assigns intervals in such a way that the same number of
regions (or as close to the same number of regions as possible) appear
in each interval. In other words, this option would assign intervals so that
each color on the map is assigned to the same number of regions. The
numeric quantity of the summary values in each interval may or may not
be equal, depending on the individual regions and their summary values.
• Equal ranges
This option assigns intervals in such a way that the summary values in
each interval are numerically equal. The number of regions in each