SetDataBorderColors — Set the rectangle border color on bars and stacked bars
$plot->SetDataBorderColors($border)
SetDataBorderColors sets the color used for the
borders of the bars and stacked bars for plot types 'bars' and
'stackedbars'. The borders are only drawn if shading is turned off
with SetShading; the default is to draw bars with
a drop-shadow for a 3-D look and no borders.
$borderThe desired color for the data borders. If this is an array, it sets the color for each data set sequentially from the array. If this is a single value, it sets the color for all data sets to that. See Section 3.5, “Colors” for more on color values.
If an array is used for $border, it
must use zero based sequential integer indexes. This is what the PHP manual
calls 'the usual integer indices (starting from zero, increasing by one)'.
If this function is never called, and SetShading is called to turn shading off, then all data borders are black.
This is only used for plot types 'bars' and 'stackedbars', and only if shading is turned off.
If you want flat (unshaded), borderless bars, call SetShading(0) to turn off the shading, and call SetDataBorderColors with the same color (or color array) that you use with SetDataColors.