Identity Operator Puns

https://i.redd.it/thvnxea9lao61.gif

So this is more of just a fun post: I'm curious if anyone had any applications or ideas which used fractional operators . I also wanted to show of my gif.

A bit of background on what's in the GIF and fractional operators in general.

Recall that the 2D discrete Fourier transform, F, is a linear operator on a space of matrices (or d by d arrays). If we apply the Fourier transform 4 times it returns the identity function i.e. F^4 = F(F(F(F))) = I. Note that people have figured out how to let these exponents take non-integer values! This corresponds to fractional Fourier transforms. So for example the half Fourier transform F^(1/2) is something that functions like the square root of the Fourier transform. If we let G = F^(1/2) then we have that G(G)=F, or maybe a bit more concretely, for any matrix/image X, we have that G(G(X)) = F(X). These special exponents behave like regular old exponents in a lot of ways and it has been observed that one can construct F^a for arbitrary real-valued a.

The GIF I've posed takes an image of a pagoda X and applies increasing fractional degrees of Fourier transforms. Specifically the graph shows shows F^a (X) as a goes from 0 to 4.

Links, more on fractional operators

• Fractional fourier transform: https://en.wikipedia.org/wiki/Fractional_Fourier_transform
• It worth nothing that its possible to take the square roots of many linear transforms thereby making it possible to construct fractional versions of these transforms in a straightforward manner. https://en.wikipedia.org/wiki/Square_root_of_a_matrix
• If you think this is cool you should also check out fractional calculus: https://en.wikipedia.org/wiki/Fractional_calculus
  (Remember, the derivative is also a linear operator 🙂....)

Conclusion
I'm curious if anyone has any interesting ideas...

Both of these are linear transformation. Identity linear mapping [ I : V --> V] and linear operators [ T : V --> V]? Book says- identity linear map forms when V maps into itself, whereas linear operator, is formed when domain = range. Then how they are different I can't get it?

Found on the Rainbow Six Siege steam community

Apologies if this has been asked before. Can someone help me understand the following:

>>> num1 = 256

>>> num2 = 256

>>> num1 == num2

True

>>> num1 is num2

True

>>> num3 = 257

>>> num4 = 257

>>> num3 == num4

True

>>> num3 is num4

False

I fail to see why the needed to include that.

I've been running my relay since 2013, and have my secret_id_key backed up.

I recently updated from a very old version (0.2.4.23) to the recent stable version of Tor (0.4.1.6).

I copied my secret_id_key over and it started up and everything was good, had the same fingerprint and showed up on the https://metrics.torproject.org explorer as updated.

Then I was doing some maintenance and accidentally nuked the Tor data dir. I restored my old secret_id_key and started up again, however now I'm getting these warnings in my logs:

>Oct 10 15:31:49.000 [warn] http status 400 ("Looks like your keypair has changed? This authority previously recorded a different RSA identity for this Ed25519 identity (or vice versa.) Did you replace or copy some of your key files, but not the others? You should either restore the expected keypair, or delete your keys and restart Tor to start your relay with a new identity.") response from dirserver '128.31.0.34:9131'. Please correct.

And the metrics site is showing my node is down while it's running.

After checking the keys directory, the newer Tor version generates some new files I'm not familiar with:

ed25519_master_id_public_key

ed25519_master_id_secret_key

ed25519_signing_cert

ed25519_signing_secret_key

I don't have those ed25519 keys from my first run backed up anywhere, I didn't know they existed. It seems like they were cached by other nodes on the first run and now they won't accept my node without the ed25519 keys. What are these keys? Are they generated randomly by the first version of Tor that uses them? Not deterministically from secret_id_key.

Is there anything I can do to resolve this?

I really don't want to nuke my keys and use a new identity, I've been running these keys for the last 6.5 years :/

Forgot to include language: Python

I'm trying to put a concept I don't quite understand into my own words and I'd like to know if I'm on the right track.

sub_reddit = CS (creates the variable "CS")

sub_reddit == CS (would evaluate as true)

sub_reddit is CS (would evaluate to false because they are "bound to different objects")

Identity Operators make "CS" a separate object or "string literal" and since this new object is stored in a different memory location than "sub_reddit", this is why it equates to true.

PS: Would this rule hold true for all programming languages?

Thanks yall and I appreciate the help in advance for helping me understand this concept a bit.

For example, a sonar operator (or the person incharge) has a contact on the surface of a ship. How does he know

1- Whose ship it is? If not your own (you might have all of their locations), it could be a friendly?

2- What type is it?

Edit: The title should be "Know the identity of a contact". Sorry.

http://www.latimes.com/local/lanow/la-me-ln-revenge-porn-sentenced-20150403-story.html

Sorry if someone has already posted this, I just saw it.