In Table 9.4 of the documentation atan2 is described as follows: atan2(*x*, *y*) inverse tangent of *x*/*y*
I am sure it should read as: atan2(*y*, x) inverse tangent of y/x This looks to be the standard C++/c atan2(y,x) function. You can easily test this: If y = 2, x = 1, then degrees(atan(y/x)) =63.4 but if we proceed according to the documentation; degrees(atan2(x,y))=degrees(atan2(1,2))=25.6 which is not the same as degrees(atan(y/x)). So it must be degrees(atan2(y,x))=degrees(atan2(2,1))=63.4. Thanks Andrew -- ___________________________________________ Andrew J. P. Maclean Centre for Autonomous Systems The Rose Street Building J04 The University of Sydney 2006 NSW AUSTRALIA Ph: +61 2 9351 3283 Fax: +61 2 9351 7474 URL: http://www.acfr.usyd.edu.au/ ___________________________________________
