Dennis Francis
84129dd550
Each series gives one arrow, from the origin to the point whose 1. x-coordinate value is the correlation of that series' feature column with the first dimension column. 2. y-coordinate value is the correlation of that series' feature column with the second dimension column. A symbol marks the tip and the feature name sits beside it. The circle of radius one and the two lines through the origin are drawn behind the arrows, and both axes are held at minus one to one on a square plot area, so a length in the picture means the same in both directions and the circle stays round. The correlations are worked out while the shapes are made rather than kept anywhere, so they follow the cells they come from. Working them out needs the whole of the three columns. The correlation coefficient code itself is in a small header of its own with a test beside it. It leaves out the instances where either side is missing, and it has no answer for a feature that does not vary or for fewer than two instances. A feature without an answer gets no arrow, as there is no direction to point in. Error bars, trend lines and area properties are turned off for this chart type, since a point stands for a worked out pair rather than for a value in a cell, and symbols are turned on because the tip of each arrow carries one. The arrows take the line colour and width of their series, and the template asks for thin ones, which is what keeps a crowd of them apart. The legend hands out the same symbol as the arrow tip, so a key can be matched to an arrow. Grids are turned off by default for this chart as the user is more interested in the direction/angles and the magnitude of the "rays" from the origin. Change-Id: I2d8b3aa6ef7d66bd9deb1f63a647767a1b62ac90 Signed-off-by: Dennis Francis <dennis.francis@collabora.com> Reviewed-on: https://gerrit.collaboraoffice.com/c/online/+/8103 Reviewed-by: Tomaž Vajngerl <tomaz.vajngerl@collabora.com> Tested-by: Tomaž Vajngerl <tomaz.vajngerl@collabora.com> (cherry picked from commit e096bfee9c85a22e8b8155944a63ee9d6f72f75a) Reviewed-on: https://gerrit.libreoffice.org/c/core/+/210465 Tested-by: Jenkins Reviewed-by: Xisco Fauli <xiscofauli@libreoffice.org>
Chart Implementation for LibreOffice Calc
The chart2 denotes a second generation re-write done to rid us of the
foul and twisted legacy chart code.
Debugging
Shortcuts
CTRL + F12 creates a layout dump based on the XShapeDumper based on SAL_WARN("chart2", ...