Polar Graphing

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To change the graph paper to a polar grid, start by clicking on the wrench in the upper right hand corner of the graph paper to open the Graph Settings menu.

 

 

To graph in polar form, write your equation using r and theta notation:

 

 

Polar graphs are automatically set to a domain of [0,12pi]. It's possible to restrict this domain using restrictions. However, it's not currently possible to use a larger domain. 

 

 

Currently, graphing polar coordinates isn't supported - but it's on our list! You can find more helpful example graphs by clicking on the three horizontal lines in the upper left hand corner of the calculator.

 

Have more questions? Submit a request

11 Comments

Date Votes
  • 2
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    Poloinc

    How would I graph the straight line through the origin

    theta=pi/4

  • 0
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    Troy Alexander

    I do not see the option of polar functions with negative values for theta, even when I set specific ranges. Will this be changed/updated?

  • 0
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    bej ugo

    Nice app! Similar to Troy's comment, I'm trying to graph the polar equation r=3.1cos(-1.1*theta). This program will only graph about 60% of it, b/c it won't let us extend the upper limit above about 12pi (and we need to let theta run from 0 all the way to 20pi in order to see this entire curve.)

    I hope the creators of this site will program in more flexibility with extending restrictions so that we can graph beautiful graphs like this one.

    Thanks, again, for such a nice program.

  • 0
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    G. W.

    Why does the spiral created by r=theta stop at r=37 and some change? Shouldn't it continue? Is this some kind of convention? Thanks for the fantastic site!

  • 0
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    Leonardo Cisija

    a quick temporary workaround for the negative theta range problem for those who need it is to replace theta with "theta + a2pi" or "theta + 360a" where "a" is a scaling factor. in the slider for a (or whichever letter you choose), write something like "a = [-50, -49, -48,..., 50]" to set your range in multiples of 2pi. it's basically drawing a bunch of different graphs of different ranges that look like one graph, which means a bigger range will take longer, but my computer can barely open ms word yet handles 600 items on that list pretty well.

    here's an example with a log function, which decays pretty fast. notice i've changed a2pi to a12pi because that's where the function usually cuts off for me that way it saves time.

  • 0
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    Wojciech Gościcki

    But is there a way for a spiral created by r = θ (or r = θ + a12π) to have less than 6 turns?

    Edit: Never mind, range restriction works fine.

    Edited by Wojciech Gościcki
  • 0
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    Flexagontnt

    Is it possible to do implicit polar equations, like r-1=sin(theta)? If so, how?

  • 0
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    Leonardo Cisija

    no, but theres always a work around. define these:
    R(x,y)=sqrt(x^2+y^2) 
    T(x,y)=arctan(y/x)+[0,...,50]pi

    now use R(x,y) and T(x,y) instead of r and theta. the example you gave can just be rewritten for r though.

    Edited by Leonardo Cisija
  • 0
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    Leonardo Cisija

    *R(x,y)=sqrt(x^2+y^2)

     

    edit: just figured out you can edit

    Edited by Leonardo Cisija
  • 0
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    Aalia Khazi

    Hi, how do I graph polar coordinates on this? I can't seem to get the degree function.

    Edit: Ohhh, I see it's not supported.

    Edited by Aalia Khazi
  • 0
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    Leonardo Cisija

    you can use a similar work-around. define these

    X=r*cos(theta)

    Y=r*sin(theta)

    then just plot it with the values for r and theta plugged-in. here's an example: https://www.desmos.com/calculator/arlph9kxks

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