Vectors and Coordinates - Emmanuel Branlard

the convention on the right side of Figure 1. This has the advantage to give directly the angles in the clockwise direction with respect to the NS axis. 1Find as an ...
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Vectors and Coordinates Emmanuel Branlard January 2011

1

System of coordinates

1.1

The example of Polar vs Cartesian coordinates

Polar to Cartesian: x = r cos θ

(1)

y = r sin θ

(2)

Cartesian coordinates to polar coordinates: r=

θ=

q

y 2 + x2

(3)

  arctan( xy )     y  arctan( x ) + π    y 

arctan( x ) − π

π    2   π   −  2   

0

if if if if if if

x>0 x