Purpose of feature: analysis of sailing, weather and sea conditions regarding current and historic tracks. A precondition for its benefit is, that you register these conditions when cruising.
Local TOC
The Piechart subpage - or just 'Piechart' - opens from:
The back button in the teal blue navigation bar displays as:
(Provided The Hide default Tzone number switch is ON and default Tzone applies - else a suffix appears, e.g. )
Its content is based on:
Like the Barchart subpage, the chart is static, i.e. it doesn't change even when opened from a).
The Piechart - as well as the Barchart - is based on the Charts library licensed under Apache License 2.0 - Copyright 2015 Daniel Cohen Gindi & Philipp Jahoda.
is placed at the top and consists of two independent wheels:
The Attribute picker to the left selects what to show:
The Timeunit picker to the right selects how to show:
*) Values shown without decimals - values for the other units are shown with one decimal.
Each type of attribute can have several discrete values, as shown in e.g. the Pickerscreen example. The distribution of these values are shown in the corresponding chart. Calculations follow these rules:
*) Check the description of The assumption switches.
The example below shows how the selected time range is displayed at the bottom of the Piechart, together with the number of tracks involved - and a legend:
Below a series of screenshots of charts follow. Registrations from the first 6 tracks of the Appetizer 2: roundtrip through Sweden were used:
48.4 perent of the time, full sails were worn. Pie slices always represent non-zero values. To examine the 0.3 percent display for Sails, 2.reef, the Timeunit picker wheel is dragged from Percent to Minutes:
It appears, that Sails, 2.reef was the situation during 8 minutes.
where the -?- stands for unset / no registration (approx. 2 hours).
Pie slice colors are random and change each time the chart is displayed. If a chart is hard to read, use the
button to generate another set:Selecting a slice by tapping it, highlights it and informs on the number of registrations from which the slice is build - here 4 registration(s):
A chart can be rotated by tapping, holding and dragging a slice. This can improve readability of the text on a slice when it's eclipsed by that of another slice.
A tap at the bottom of the chart un-selects the slice and revokes the Time range display.
Rotation is almost impossible when not in Full screen presentation style.
If nothing was registered for an attribute type for tracks in the given time range, the chart turns monochrome:
In this case, no current direction was registered for a single track (day), so the label is -?-. This is not the same as actively registering no current, which is represented as nil.
Active registration of nil is possible for:
Sailor Logbook S App manual - © Copyright 2018 CoaSoft ApS Denmark