This is a perfect introduction to the topic of problems with atan. Many of my friends dont have a intuition for the complex plain, so i hope this series will help them. Thank you!
AE 501. I haven't ever been aware of this SW bug but it makes sense and I've usually just added the degree offset when drawing out the problem to correct the final answer. Thanks for the explanation!
AE501 Student- Great refresher on Cos/Tan ACos/ATan, etc and quadrant systems. The reminders for differences in Matlab and Mathematica coding applications are good too.
[AE501] 16:50 I never even realized this was a problem with tangent (and other functions). I have not run into this problem in professional life but your airplane vector is an excellent example.
AE 501: I have always used atan2 but was never told why. This gave me a background to understand why i am doing something rather than just being told to do it which is extremely helpful.
Used it in programming for a couple of years without even knowing what it did. I understand now. Learning all of this in high school so it's not horrible in uni.
Such a good explanation! I like the way you showed how atan2 function is implemented in softwares. I also like how you showed everything by plotting a graph, it really helped me understood how the trig. inv. functions work and how the range and domain are decided.
Hi Chris! I had seen you use atan2 and acos2 on some of the homeworks and lecture notes, and always wondered why. Now I know! Excellent video explaining those functions and their uses. Thanks for sharing! @AE501
AE501. Never would have thought about this issue, great video. I'm curious how other programming languages address this issue as well. At my previous jobs I have used a multitude of languages ranging from Fortran, to C++, to Ada so I'm interested to see if/how they make the designation between atan and a 4 quadrant inverse tangent function. Thanks!
AE 501: Mathematica looks more intuitive to me in comparison with MatLab so far, as all software I've used in the past adopt [x,y] as opposed to [y,x]. Thank you for making these videos Chris!
Hi, Thanks for the kind words, I'm glad you enjoyed the video. If the find the these videos to be helpful, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum. Given your interest in this topic, I'd love to have you a as a Patron as I'm able to talk/interact personally with all Patrons. Thanks for watching! -Chris
AE501. Rapid commenting among other videos because I totally forgot to comment on these awesome videos but I swear I've watched them! haha. Definitely not the biggest fan of such crucial difference in the arctan functions between MATLAB and Mathematica.. They should just shake hands and be friends. Another great video Professor.
AE 501. Thank you for the "warning sign" 14:34. Did not realize the position of x, y is different in Mathematica and MATLAB before this video. I will definitely pay more attention to this issue while using this two software.
AE 501. The video explaining how to use atan2 and acos2 functions with Matlab or Mathematica, and it makes me understand how the functions run by hand. thank you Chris
I need to derive the atan2 function with respect to a quaternion, my question is: Can I use the methodology as if it were the arctangent function? thank you very much Chris
AE501 It seems that atan2 defaults to negative degrees if the vector lies in the lower quadrants. I'm used to using positive degree values so that might take a bit to get used to.
AE 501: Hey Chris! Thanks for the quick trig refresh. I am a little confused by the acos2 function. You kind of talk about it in hypotheticals in the video. Is this a function that is built into matlab or hypothetically a function the user could write and use as you mention in the video? Thanks!
AE501: With the implementation of atan2(*), do you think there is still a need to include the atan(*) function? I’m trying to think of a scenario where having accurate quadrant information contained in the output of the function would be both problematic and difficult to deal with. I’m probably overlooking something, but it seems to me that the software developers could’ve just written the logic tree into atan(*) such that atan2(*) would not be necessary. It seems like in most cases this would result in a simpler user experience. Maybe they felt it was important to have a function that would match the output of a scientific calculator?
Seth, I agree with you. There is nothing that atan does that atan2 doesn't do better. I would recommend forgetting about atan and just use atan2. The only thing to worry about is how different software packages implement the 4-quadrant inverse tangent (Matlab and Mathematica use a different input order, if you get it confused you'll get incorrect results).
Hi, Thanks for the kind words, I'm glad you enjoyed the video. If you find these videos helpful, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum or via the 'Thanks' button underneath the video. Given your interest in this topic, I'd love to have you a as a Patron as I'm able to talk/interact personally with all Patrons. Thanks for watching! -Chris
AE501, Usually in my career, atan is used to find geometry with arbitrary direction-assignment, symmetric repetition and otherwise not-spatial relations. This looks very good for practical dynamic problem solving. Is it mainly dynamics or does this get applied frequently in other areas?
Hi Loo, Thanks for reaching out, I'm glad you enjoyed the video. Unfortunately I'm unable to respond to questions on TH-cam due to the sheer volume of inquiries that I receive. That being said, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum or via the 'Thanks' button underneath the video as I'll be able to answer questions there. Given your interest in the topic, I'd love to have you as a Patron as I'm able to talk/interact personally with Patrons. Thanks for watching! -Chris
Hi, Thanks for the kind words, I'm glad you enjoyed the video. If you find these videos helpful, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum or via the 'Thanks' button underneath the video. Given your interest in this topic, I'd love to have you a as a Patron as I'm able to talk/interact personally with all Patrons. I can also answer any questions you might have about any of the videos on Patreon. Thanks for watching! -Chris
AE501 I played around atan2 in MATLAB. Looks like the limits on its output are -3.14 to +3.14 (or with rad2deg conversion, -179 to +179). I could see a scenario where I would want my output to be between 0 and 359 degrees, is there a function to do this? Otherwise I would need an "if" statement to add 360 degrees to negative outputs. if theta
@@ChristopherLum Yeah sorry I'm rounding off. More like 179.9426 if I put in rad2deg(atan2(1,-999)). :) I was also able to get 180 and -180 by putting in 0 and -0 respectively for "y". I didn't know that a zero is sign-sensitive in MATLAB.
Hi habcollector, First let me say thank you for your generous support of the channel, it is very much appreciated! Do you have any particular interests in terms of videos or topics? I try to prioritize request made by interested parties as much as possible as I plan future videos. In any event, I want to again say thank you for your contribution and for supporting the channel. I hope to hear from you at a future TH-cam video or on Patreon! -Chris
@@ChristopherLum You are welcome. This video helped me understand a problem with magnetic angle and field strength I am working on - so it added value to me. TH-cam is a power for good thanks for sharing.
You are the GOAT for making this vid so easy to understand.
took my ignorant ass and got me educated.
AE 501: This is an excellent refresher on the basics of trigonometry and their inverse functions. Thank you, Professor!
This is a perfect introduction to the topic of problems with atan. Many of my friends dont have a intuition for the complex plain, so i hope this series will help them. Thank you!
I'm glad it was helpful, thanks for watching!
AE 501. I haven't ever been aware of this SW bug but it makes sense and I've usually just added the degree offset when drawing out the problem to correct the final answer. Thanks for the explanation!
AE501: great refresher of trigs!
AE501 Student- Great refresher on Cos/Tan ACos/ATan, etc and quadrant systems. The reminders for differences in Matlab and Mathematica coding applications are good too.
AE501
I would have tried to hard code in the atan2 function if I didn't know about this. Definitely a time and error saver.
[AE501] 16:50
I never even realized this was a problem with tangent (and other functions). I have not run into this problem in professional life but your airplane vector is an excellent example.
I'm glad it was helpful, I'm sure you'll see this more than once in the MAE program :)
AE501: I did not know the functions in Mathematica to call for Arc Tan. This video was useful!
Yes, just be careful as ArcTan in Mathematica is called differently than atan2 in Matlab.
AE501: I hadn't considered these limitations of our SW tools. Interesting lecture!
AE 501: I have always used atan2 but was never told why. This gave me a background to understand why i am doing something rather than just being told to do it which is extremely helpful.
Used it in programming for a couple of years without even knowing what it did. I understand now. Learning all of this in high school so it's not horrible in uni.
AE501: RTFM!! haha, thank you for the refresher and the knowledge of the atan2, acos2 functions. Very helpful to know
AE501: Thank you for an example with applicability to Aircrafts!
Thank you for sharing this video which is versy important to calculate the argument of complexe numbers
You are a magnificent teacher.
Brilliant explanation!
Such a good explanation! I like the way you showed how atan2 function is implemented in softwares. I also like how you showed everything by plotting a graph, it really helped me understood how the trig. inv. functions work and how the range and domain are decided.
This made sense! Thank you!
Hi Chris!
I had seen you use atan2 and acos2 on some of the homeworks and lecture notes, and always wondered why. Now I know! Excellent video explaining those functions and their uses. Thanks for sharing!
@AE501
AE501. Never would have thought about this issue, great video. I'm curious how other programming languages address this issue as well. At my previous jobs I have used a multitude of languages ranging from Fortran, to C++, to Ada so I'm interested to see if/how they make the designation between atan and a 4 quadrant inverse tangent function. Thanks!
Enjoyed the video. Very helpful tips for programming in MATLAB and Mathematica. (AE 501)
AE501: Never knew about atan2 etc.! Super useful, but why can’t Matlab and Mathematica get along!?
AE 501: Mathematica looks more intuitive to me in comparison with MatLab so far, as all software I've used in the past adopt [x,y] as opposed to [y,x]. Thank you for making these videos Chris!
Just be sure to be careful, Matlab wants (y,x), this is an easy place to introduce bugs!
Thank you so much, you video explains some questions bothering me for a long time
Hi,
Thanks for the kind words, I'm glad you enjoyed the video. If the find the these videos to be helpful, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum. Given your interest in this topic, I'd love to have you a as a Patron as I'm able to talk/interact personally with all Patrons. Thanks for watching!
-Chris
AE501: Great caution note on potentially using the incorrect inverse trig function in MATLAB or Mathematica!
[AE501] I think its interesting to see certain things explained again after not seeing it in so long
Fantastic stuff on atan2, thanks so much Mr. Lum!
AE501. Rapid commenting among other videos because I totally forgot to comment on these awesome videos but I swear I've watched them! haha. Definitely not the biggest fan of such crucial difference in the arctan functions between MATLAB and Mathematica.. They should just shake hands and be friends. Another great video Professor.
Ryo, I agree, it seems like they sometimes do things differently just because they are different companies.
[AE 501 Jennifer Johnson] Nice application to airplanes. It makes it more exciting to learn when it relates to real world situations.
AE 501. Thank you for the "warning sign" 14:34. Did not realize the position of x, y is different in Mathematica and MATLAB before this video. I will definitely pay more attention to this issue while using this two software.
Ian, yep, they get tricky sometimes so be sure to watch out :)
AE 501. The video explaining how to use atan2 and acos2 functions with Matlab or Mathematica, and it makes me understand how the functions run by hand. thank you Chris
I need to derive the atan2 function with respect to a quaternion, my question is: Can I use the methodology as if it were the arctangent function? thank you very much Chris
AE501 It seems that atan2 defaults to negative degrees if the vector lies in the lower quadrants. I'm used to using positive degree values so that might take a bit to get used to.
AE 501: Hey Chris! Thanks for the quick trig refresh. I am a little confused by the acos2 function. You kind of talk about it in hypotheticals in the video. Is this a function that is built into matlab or hypothetically a function the user could write and use as you mention in the video? Thanks!
This is more something that you might need to implement if your particular application warrants.
AE501:
With the implementation of atan2(*), do you think there is still a need to include the atan(*) function? I’m trying to think of a scenario where having accurate quadrant information contained in the output of the function would be both problematic and difficult to deal with. I’m probably overlooking something, but it seems to me that the software developers could’ve just written the logic tree into atan(*) such that atan2(*) would not be necessary. It seems like in most cases this would result in a simpler user experience. Maybe they felt it was important to have a function that would match the output of a scientific calculator?
Seth, I agree with you. There is nothing that atan does that atan2 doesn't do better. I would recommend forgetting about atan and just use atan2. The only thing to worry about is how different software packages implement the 4-quadrant inverse tangent (Matlab and Mathematica use a different input order, if you get it confused you'll get incorrect results).
Thanks, that was well explained.
Hi,
Thanks for the kind words, I'm glad you enjoyed the video. If you find these videos helpful, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum or via the 'Thanks' button underneath the video. Given your interest in this topic, I'd love to have you a as a Patron as I'm able to talk/interact personally with all Patrons. Thanks for watching!
-Chris
AE501, Usually in my career, atan is used to find geometry with arbitrary direction-assignment, symmetric repetition and otherwise not-spatial relations. This looks very good for practical dynamic problem solving. Is it mainly dynamics or does this get applied frequently in other areas?
I've seen it mostly in dynamics and flight mechanics but really you should be using it anywhere where the angle might be more than 90 deg.
Great video! I really needed this, just one question, why do you add pi in one of the cases and subtract pi in the other one? thank you!
Hi Loo,
Thanks for reaching out, I'm glad you enjoyed the video. Unfortunately I'm unable to respond to questions on TH-cam due to the sheer volume of inquiries that I receive. That being said, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum or via the 'Thanks' button underneath the video as I'll be able to answer questions there. Given your interest in the topic, I'd love to have you as a Patron as I'm able to talk/interact personally with Patrons. Thanks for watching!
-Chris
Okay. This is too awesome i barely understand anything... darn it..
awesome
EXELLENT!
Hi,
Thanks for the kind words, I'm glad you enjoyed the video. If you find these videos helpful, I hope you'll consider supporting the channel via Patreon at www.patreon.com/christopherwlum or via the 'Thanks' button underneath the video. Given your interest in this topic, I'd love to have you a as a Patron as I'm able to talk/interact personally with all Patrons. I can also answer any questions you might have about any of the videos on Patreon. Thanks for watching!
-Chris
AE501. I would have tried to hardcode in the atan2 function if I didn't know about this.
at 10:14, x=-10m/s on the graphic.
Hi Chris, I am doing the ArcTan (-10,-4), However I am not getting the same results.
AE501 I played around atan2 in MATLAB. Looks like the limits on its output are -3.14 to +3.14 (or with rad2deg conversion, -179 to +179). I could see a scenario where I would want my output to be between 0 and 359 degrees, is there a function to do this? Otherwise I would need an "if" statement to add 360 degrees to negative outputs.
if theta
Thomas, the precision should be much higher than that. I think you are likely rounding the answer off or cutting off the sig figs in the display.
@@ChristopherLum Yeah sorry I'm rounding off. More like 179.9426 if I put in rad2deg(atan2(1,-999)). :)
I was also able to get 180 and -180 by putting in 0 and -0 respectively for "y". I didn't know that a zero is sign-sensitive in MATLAB.
Thanks!
Hi habcollector,
First let me say thank you for your generous support of the channel, it is very much appreciated!
Do you have any particular interests in terms of videos or topics? I try to prioritize request made by interested parties as much as possible as I plan future videos.
In any event, I want to again say thank you for your contribution and for supporting the channel. I hope to hear from you at a future TH-cam video or on Patreon!
-Chris
@@ChristopherLum You are welcome. This video helped me understand a problem with magnetic angle and field strength I am working on - so it added value to me. TH-cam is a power for good thanks for sharing.
Holy fuck.
You busted my brain... an infinite number of possible solutions for an angle's tangent. OK!
RTFM - Read The Fucking Manual