# Polar Plotting Mathematica

• Mathematica
Gold Member
Why is it when I plot a circle from ##\theta \in [\pi/2,-\pi/2]## I get the right side of the unit circle:

PolarPlot[1, {\[Theta], \[Pi]/2, -\[Pi]/2}]

? Shouldn't I get the left side?

Orodruin
Staff Emeritus
Homework Helper
Gold Member
No. It is perfectly in order. ##\theta = 0## is the positive ##x##-axis and is part of your plot. ##\theta = \pi## is the negative ##x##-axis and is not part of your plot.

jedishrfu
Dale
Mentor
2020 Award
Why is it when I plot a circle from ##\theta \in [\pi/2,-\pi/2]## I get the right side of the unit circle:

PolarPlot[1, {\[Theta], \[Pi]/2, -\[Pi]/2}]

? Shouldn't I get the left side?
Note that ##\theta=0## is in the range from ##\pi/2## to ##-\pi/2##, so you expect to get the side of the circle containing 0.

What you want is the range from ##\pi/2## to ##3\pi/2## which does not contain 0.

joshmccraney
Gold Member
this makes tons of sense, thanks!