## boot – Problem with Dwnld IOS & USB ‘pre-install enviro” bootable disc- start over or de-bug/ fix?

I have a serious problem:
I downloaded the Ububtu ISO to my HD & used RUFUS to create the (?) “pre-install enviro” (?) USB- I then booted from that USB & the O/S, looked like freddy kruger slashed the pages to sh*t.- is there a fix or do I spend another 2 days (14 hrs) downloading the program all over again?

Thanks for the help to the 3 dudes & admin who answered my 1st Q- really awesome being part of the open source community- THAT is the way the internet should have been designed from the jump… peer to peer anonymity, no storing info on server- just passes thru server- so even if they strong arm a ceo & he buckles no info to STEAL- yes it IS stealing info- we don’t need to re-write the 4th Am because dude invented a new device/toy… whether it is a physical person or virtual person- secure in papers/webpages physical or virtual, property & person physical or virtual… TRUTH & FACT YO!

Anyway let me find out uberevil corporoverlord Bill darthgateicus has nested disruptor progs in the windows progs such that anyone attempting to escape the slavery to windows O/S has their files corrupted during even a secure download session(s)

The boot from USB result was a dysfunctional ubuntu- liteally looks like the pages were torn rotated 45 degrees & only one of the resulting isoceleces triangle shaped shards even appears… I can’t even choose a GUI tho the choose english & somewhat choose try rather than install option does work despite the page being all messed up!

Is there a fix or do I begin all over again from the jump???

And thanks again I know at the mo I don’t know anything but I am not a dummy so after a while I actually may even be able to help. Appreciate all the open source community members who know that if freedom & liberty are to be defended from the burgeoning global surveillance police state & empire… that war in order to be successful MUST be fought on an OPEN SOURCE BATTLE FIELD because criminals are DUMB & GOD has reserved the dominion of wisdom to himself… ONLY GOD decides who is wise… not man or man’s institutions… FACT & TRUTH
Open Source ensures its ultimately the WISE Vs the dummies & cunning… so essentially good will triumph within that construct just as it is being censored & deleted without anyone even knowing of it under the present corporofascist paradigm!
Thanks again for all the help.

PROB: Ubuntu ISO or USB “pre-install enviro” NO JOY

Q1: Do I start over from ZERO… or is there some de-bugging program I can run & if so are these run in windows command prompt?

Q2: is there a UBUNTU user guide for beginners?

## Disc film cameras that use replacable batteries?

I have some Disc Film in the fridge that I would like to use, that I got from a film lot.

It seems unlikely that anything amazing will come out of it, but experimenting is part of my process and some recent results look really cool.

I found a lab that processes it, but I don’t own a Disc camera. They seem to cost a dime a dozen on second-hand marketplaces, however, I recall from using one in the past that the batteries are usually not removable by the user, to save space and make a thin camera (they are welded inside the body) – and therefore, batteries from this period might have ran out of juice or become damaged if I just bought any such model.

Given that over 30 different manufacturers made cameras that use disc film, I wonder if some of them were smart enough to design them to use regular, removable batteries.

These types of cameras are very under-documented across the internet.

## A Disc Camera likely to be usable in 2021

I have some Disc Film in the fridge that I would like to use, that I got from a film lot.

It seems unlikely that anything amazing will come out of it, but experimenting is part of my process and some recent results look really cool.

I found a lab that processes it, but I don’t own a Disc camera. They seem to cost a dime a dozen on second-hand marketplaces, however, I recall from using one in the past that the batteries are usually not removable by the user, to save space and make a thin camera (they are welded inside the body) – and therefore, batteries from this period might have ran out of juice or become damaged if I just bought any such model.

Given that over 30 different manufacturers made cameras that use disc film, I wonder if some of them were smart enough to design them to use regular, removable batteries.

These types of cameras are very under-documented across the internet.

## hard drive – Cannot erase disc in disc utility before trade in

Looking for some help please.

I am preparing my 2014 MacBook for a trade in. I followed the instructions that Apple sent but failed on the ‘turn FileVault off’ stage. I did this, but my prediction now is that at some point during the process my battery went flat as everything I’m reading implies that my disc is still encrypted.

I booted up into recovery mode to complete the Erase Hard drive and reinstall MacOS process.
Using Disc Utility I then erased the top disc it showed me – 251 GB Apple SSD SM0256F Media.

I then went to erase the 2nd disc it showed Mac OS X Base System (which shows 1.15GB used)
However I am unable to erase this in Disc Recovery. In the Erase tab the ‘erase free space’ / security options / erase buttons are all greyed out.

How can I erase this disc? Presumably this is what I need to reinstall MacOS as currently when I try to run reinstallation from disc recovery no disc shows in the installation dialog

Thanks so much

## Is checking disc necessary while booting Ubuntu from USB?

I am booting Ubuntu from USB. Initially it checks disk for about five minutes. Is this step necessary? Is there any problem if press `ctr + C`?

## functional analysis – Extreme Points of Disc Algebra

I know that the extreme points of the closed unit ball of $$mathcal{H}^infty(mathbb{D})$$, the space of all bounded holomorphic functions on the unit disc are the functions $$finmathcal{H}^infty(mathbb{D})$$ such that $$intlimits_{-pi}^pilog(1-|f(e^{itheta})|)dtheta=-infty$$. What are the extreme points of the closed unit ball of the disc algebra, i.e. all functions continuous on $$overline{mathbb{D}}$$ and holomorphic on $$mathbb{D}$$?
It is clear that all the extreme points of the closed unit ball of $$mathcal{H}^infty(mathbb{D})$$, that are in the disc algebra are extreme points of the closed unit ball of the disc algebra. But are these the only extreme points?
Are there any extreme points of the closed unit ball of $$mathcal{H}^infty(mathbb{D})$$ that is not in the disc algebra?
Is there any extreme point of the closed unit ball of the disc algebra that is not a finite Blaschke product?

## compact disc – Copy errors from CD for file that plays from CD successfully

I am trying Unstoppable Copier based on the answer in this question. While the copy hasn’t yet outright failed, it has been experiencing a significant error rate. This seems odd as the file seems to play completely fine from the CD itself and there are no apparent scratches or damage to the CD itself.

Could anyone give me an idea as to what might be the root of the issue? This might be a nuance I’m unaware of, but if the file plays without error the data would seem to be fine; so copy errors would seem like they shouldn’t happen in any method of file copying. But they are so I’m just hoping to learn (and maybe find a way to address the source of the copy errors more directly).

## security – Self Encrypting Disc (SED) enabled SSD password / key requirements

Several `SSD` manufacturers have released Self Encrypting Disks (SEDs) which use `hardware encryption` on the disk.

This is `OS` agnostic, and should generally be faster than software based encryption like `LUKS-dmCrypt` or `Bitlocker` etc.

However, I could not clarify if such a disk, and encryption, if used, would always require a password prompt upon reboot.

As I understand it, the password / key for these SEDs is generally stored inside a special `ATA password` field in `BIOS`. When `OS` boots, the disk looks to this password / key and decrypts, and remains decrypted as long as `OS` is in session. But am not sure whether it prompts the user for a password and does a match upon reboot or decrypts without any intervention..

Currently, I require the disk to not require any password prompt upon system boot, it should take it from the `BIOS`. I know that if the PC gets stolen, then data is exposed, but at least I want to ensure that disk theft will not cause data exposure.

If this is not possible, that a `SED` will always ask for a password prompt when `OS` boots, would it help if the `key` be placed in a `TPM` instead, assuming that is possible, not sure if it would make a difference though.

## complex analysis – Prove the Analytic Function \$f(z)\$ on the Unit Disc Satisfies \$f(z) leq |dfrac{z – alpha}{1 – bar{alpha) z}|\$

I’m trying to solve the following problem, but I’m completely stuck on how to proceed. The function $$f$$ is analytic on its domain $$mathcal{D} = {z in mathbb{C} : |z| < 1}$$, has a root at $$alpha rightarrow f(alpha) = 0$$. Prove:

$$|f(z)| < 1 forall z in mathcal{D} implies |f(z)| leq | dfrac{z – alpha}{1 – bar{alpha} z}|$$

Where $$bar{alpha}$$ is the complex conjugate of $$alpha$$. Also I think we can assume $$f$$ is continuous on $${ z in mathbb{C} : |z| leq 1 }$$.

My solution:

The only thing I could come up with was to solve this like proving Schwarz’ Lemma, which basically proves this problem for the special case $$alpha = 0$$. Since $$alpha=0$$ is already a known case because of the said lemma, I will assume $$alpha neq 0$$. Suppose we divide $$f$$ by $$z – alpha$$. The result would be analytic on $$mathcal{D}$$(the singularity at $$alpha$$ would be removeable, so we can just remove it), and then we can proceed as:

$$g(z) equiv dfrac{f(z)}{z – alpha} implies |g(z)| leq dfrac{1}{|z – alpha|}$$

Now using the maximum principle, we know $$|g(z)|$$ is maximized somewhere on $$|z|=1$$. Since the smallest |z – alpha| we can get along $$|z|=1$$ is when $$z = dfrac{alpha}{|alpha|}$$, we have:

$$|g(z)| leq dfrac{1}{| dfrac{alpha}{|alpha|} – alpha|}$$

$$implies |f(z)| leq dfrac{|z-alpha|}{|dfrac{alpha}{|alpha|} – alpha | }$$

## connect wifi internet in external hard disc dur

I installed windows 10 on an external hard disc, this last is attached to my pc laptop via usb, while starting this pc I directly access the hard disc from boot (bios) so how can I connect on wifi internet from this hard disk, thank you in advance