That's makes it all the more bizarre...Ok for me...
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Hi Stefan -- The convention for 2D Axis is the X+ axis going horizontally to the right and the Y+ axis 90° anti-clockwise to that to make the Right Hand Rule effective. Add a 3rd Dimension to that and the Z+ axis goes "up" (the direction your right hand thumb points when your "fingers" sweep from X+ to Y+. [That is the definition of the Right Hand Rule.] -- LewHello Lew,
is it also ok to suspect the first plots on a computer screen have been 2D (x-y like them on paper at school...x up and y to the right), then the third dimension vector was simply added in a direction to the screen, to let the geometry grow out of the monitor... and there you have the right hand rule and so on...