In the equation for azimuth, the symbol θ (lower case Greek theta) appears to be used for the latitude. However, on the previous page φ (lower case Greek phi) is used. It would be nice (and less confusing) if the equation on this page was changed to use φ so it is consistent with the prior pages. Otherwise the symbols used on this page should be defined on this page. Also, the equation should be Azi = cos . . . since Azi is used in the following two equations to calculate the actual Azimuth angle with the correct sign.
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The azimuth angle is defined to be (at equator) 270° at sunset. However the animation shows there angle amplitude equal to 90°.
This is just an example. More in general the whole graphical representation of azimuth for me needs revising.