Comments on: Batman logo in equation form

By: Jhonny Be Good

Jhonny Be Good — Sun, 31 Jul 2011 21:17:00 +0000

Guys, the solution to the equation is complex (has imaginary part). The batman figure is one of the real solutions, that is what usually software will plot. The trick is done, for example, by the factor sqrt(abs( abs(x)-3 ) /abs(x)-3 ), that will be imaginary for x3, so the grapher will not be able to plot in the interval x<3, but the solution is still there!

By: Hee S. Lee

Hee S. Lee — Sat, 30 Jul 2011 19:14:00 +0000

can somebody come up with the equations for wu-tang logo?

By: hypnosifl

hypnosifl — Sat, 30 Jul 2011 17:37:00 +0000

Grapher seems to have a kind of messed up way of handling expressions unless you type in a bunch of parentheses…for example, here are two sample inputs (with the first sqrt[...] being a term from the Batman equation) which give different responses:

sqrt[abs[abs[x] – 3]/(abs[x] – 3)] + xy = 0 (gives “no valid operation found”)

sqrt[(abs[abs[x] – 3])/(abs[x] – 3)] + xy = 0 (gives a working graph…only difference is parentheses around “abs[abs[x] – 3]”, shouldn’t the brackets be enough?)Anyway, that gripe aside, I tried taking a version of the equation posted by someone on the reddit thread and fixing it up a little to work in Grapher, Grapher was able to graph the 6 different parts of the equation individually (though with some it gave weird dotted lines at the end):(((x/7)^2)*sqrt[(abs[abs[x] – 3])/(abs[x] – 3)] + ((y/3)^2)*sqrt[(abs[y + (3*sqrt[33])/7])/(y + (3*sqrt[33])/7)] – 1) = 0

(abs[x/2] – ((3*sqrt[33] – 7)/112)*x^2 – 3 + sqrt[1 - (abs[abs[x] – 2] – 1)^2] – y) =0

(9*sqrt[(abs[(abs[x] – 1)*(abs[x] – 3/4)])/((1 – abs[x])*(abs[x] – 3/4))] – 8*abs[x] – y) = 0

(3*abs[x] + (3/4)*sqrt[(abs[(abs[x] – 3/4) (abs[x] – 1/2)])/((3/4 – abs[x])*(abs[x] – 1/2))] – y) = 0

((9/4)*sqrt[(abs[(x - 1/2)*(x + 1/2)])/((1/2 – x)*(1/2 + x))] – y) = 0

((6*sqrt[10])/7 + (3/2 – abs[x]/2)*sqrt[(abs[abs[x] – 1])/(abs[x] – 1)] – ((6*sqrt[10])/14) *sqrt[4 - (abs[x] – 1)^2 ] – y) = 0

But when I tried multiplying them together into one giant equation and setting it all equal to zero, Grapher didn’t give an error but it also didn’t show anything on the graph. Maybe it’s too much for it to handle…

By: Paul Munro

Paul Munro — Sat, 30 Jul 2011 16:26:00 +0000

It looks like the Grapher application, in the Applications/Utilities folder of EVERY Macintosh running OS X…

By: hypnosifl

hypnosifl — Fri, 29 Jul 2011 23:50:00 +0000

So for that implicit function applet I linked to, here’s the first of the six big expressions in parentheses, which gives the outer edge of the logo’s wings (set the range on the graph to xmin=-8, xmax=8, and also for ymin and ymax if you don’t want the shape distorted):

( ( ((x/7)^2) * sqrt( (abs(abs(x) – 3)) / (abs(x) – 3) ) ) + ( ((y/3)^2) *sqrt( (abs(y + (3*sqrt(33)/7))) / (y + (3*sqrt(33)/7)) ) ) – 1 ) = 0

By: hypnosifl

hypnosifl — Fri, 29 Jul 2011 23:32:00 +0000

I don't think Wolfram Alpha's equation plotter allows you to plot implicit functions, you'd have to solve for y if you wanted to use it. There's an applet for implicit functions here, haven't tried it though.

By: Astrid Torregroza

Astrid Torregroza — Fri, 29 Jul 2011 23:04:00 +0000

http://proyectosilueta.blogspot.com/

By: kumar mayank

kumar mayank — Fri, 29 Jul 2011 22:15:00 +0000

can someone type the text so that I can plot on Wolfram Alpha and confirm?

By: hughstimson

hughstimson — Fri, 29 Jul 2011 21:16:00 +0000

Are you suggesting Wolfram Alpha could be used to plot that beast? Awesome! And I nominate you sir!

By: sarah michel

sarah michel — Fri, 29 Jul 2011 18:44:00 +0000

I think it’s probably in units of the square root of two, rather than units of 1.4, which would certainly be somewhat more significant.

By: Chris Brown

Chris Brown — Fri, 29 Jul 2011 17:56:00 +0000

How long before someone posts a link to wolfram alpha?

By: Haakon IV

Haakon IV — Fri, 29 Jul 2011 17:38:00 +0000

I have discovered a remarkable analytic function representing the bat signal, which this comment is unfortunately to small to contain.

By: Robert Holmén

Robert Holmén — Fri, 29 Jul 2011 17:34:00 +0000

What is the reason for the paper being labeled in units of 1.4? How is that generally more useful than integers?

By: Leandro M.D.

Leandro M.D. — Fri, 29 Jul 2011 16:59:00 +0000

Very good!!

By: Christopher Rogers

Christopher Rogers — Fri, 29 Jul 2011 15:47:00 +0000

It shows that almost everything can be described by the language of maths.

By: omems

omems — Fri, 29 Jul 2011 15:47:00 +0000

How long until DC issues a DMCA takedown notification?

By: Joel Phillips

Joel Phillips — Fri, 29 Jul 2011 15:17:00 +0000

sqrt{frac{||x| - 1|}{|x|-1}} is cheating.

By: anne speck

anne speck — Fri, 29 Jul 2011 15:02:00 +0000

@google-6e7df99bb682d2a2604859f86ea75e01:disqus D’oh! You’re right of course — polar would have made for a much cleaner equation. Apologies for my pre-coffee posting.

By: Jacob Ewing

Jacob Ewing — Fri, 29 Jul 2011 14:48:00 +0000

Ok, that beats my mammary math by a long shot.

By: Camilo Wartenberg

Camilo Wartenberg — Fri, 29 Jul 2011 14:01:00 +0000

Sorry this is a better page to view all the works in the same page:

http://proyectosilueta.blogspot.com/p/la-propuesta.html

By: john aguirre

john aguirre — Fri, 29 Jul 2011 14:01:00 +0000

That is a stepwise equation, but it is definitely not polar, it’s Cartesian. Note that the variables are (x,y), not (r,theta).

By: Camilo Wartenberg

Camilo Wartenberg — Fri, 29 Jul 2011 13:59:00 +0000

A school in Bogota Colombia did a whole project similar to this earlier this year using the educational math software Cabri and Derive.

Memorable works include the Metallica logo, Adidas logo, Thundercats logo

You can view the works in:

http://proyectosilueta.blogspot.com/p/bocetos.html

By: Ambiguity

Ambiguity — Fri, 29 Jul 2011 13:52:00 +0000

But the function isn’t analytic! I mean, look at those derivatives. Just look at ‘em!

By: eaddict

eaddict — Fri, 29 Jul 2011 13:48:00 +0000

My daughter ‘s math class did that last year. In fact, she did the Batman logo, others did the St Louis Cardinals letter logo, while others did various product logos. Nice to see other teachers going the creative route.

By: anne speck

anne speck — Fri, 29 Jul 2011 13:38:00 +0000

It’s a step-wise polar equation. It probably doesn’t do anything other than make a space in minds which have been learning in the graphs=cartesian coordinates world for other kinds of plotting systems do exist. And why is it important to put it on larger graph paper? Take the formula and plug it into Geogebra and print it out as big as you want.

By: awjt

awjt — Fri, 29 Jul 2011 13:37:00 +0000

I = b(a*t)+ma^n

By: unwesen

unwesen — Fri, 29 Jul 2011 13:30:00 +0000

That must be the ultimate nerdgasm: comics and mathematics combined.

By: Andrew Singleton

Andrew Singleton — Fri, 29 Jul 2011 13:21:00 +0000

Gonna have to agree. We need more teachers like this.

Query: other than drawing the bat symbol… is it good for anything?

By: nffcnnr

nffcnnr — Fri, 29 Jul 2011 13:09:00 +0000

If this guy’s so smart, why didn’t he think of putting it on a larger piece of graph paper?

By: Goldie Knight

Goldie Knight — Fri, 29 Jul 2011 13:07:00 +0000

Wonderful batman, is that a special formular or what?