# Tag: machine

## backup – iCloud Notes – back up to Time Machine or Optimise Mac storage

my original question was,

are my iCloud notes automatically backed up to Time Machine?

online I came upon the answer, yes, as long as Optimise Mac Storage is turned off

is this true?

But Optimise Mac Storage means full content of the iCloud Drive will be stored on the Mac

So it seems that’s already a way to backup the iCloud

Does this mean I have to choose whether to back it up to the Mac or to Time Machine ?

Which would be better ?

Thank you !

## arithmetic – How can I do a subtraction with a two tape Turing machine

I have already made a Turing machine with just one tape that solves a subtraction between two numbers, but I trying to do the same but with TWO tapes.

As an example, how can I solve 4-2?

Taking account that 4 can be represented as 0000, 2 as 00 and the – as 1.

So, in this case the input will be 0000100.

## Does the miner machine get any other type of reward except confirmation of transaction in bitcoin?

Does the miner machine get any other type of reward except confirmation of transaction in bitcoin?(The answer precedes another question)

## formal languages – Turing machine that accepts $L = {a^{n^2}|ngeq 1}$

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I have the following language:

$L = {a^{n^2}|ngeq 1}$

Hey i have been stuck on this problem for a few days now and even going through sample problems in my textbook as well as sample solutions i cant figure out how to make this turing machine to work.

I know it may be a vague question but i really could use some help figuring this one out.

Thanks in advance!

$endgroup$

2

## formal languages – Turing machine that accepts 𝐿={𝑎𝑛2|𝑛≥1}

I have the following language:

$ 𝐿={𝑎^𝑛^2|𝑛≥1}

Hey i have been stuck on this problem for a few days now and even going through sample problems in my textbook as well as sample solutions i cant figure out how to make this turning machine to work.

I know it may be a vague question but i really could use some help figuring this one out.

Thanks in advance!

## Why is the Turing machine rather than the finite automaton the main model for computation if computers have finite memory?

Any physical computational device clearly has finite memory. On the other hand the input can be external and could therefore potentially be infinite. This idea is perfectly captured by the deterministic finite automata (DFA), so why do we use the Turing machines instead?

Let’s consider a popular example. The language

$$L = {a^nb^n, nin mathbb{N} } $$

is recognizable by a Turing machine, but not by a DFA. Suppose that you are getting a string from a server, and you need to determine whether it belongs to $L$ or not. I’d say you can’t do it, because you might, in fact, run out of memory.

## Why are my Mac and Windows machine able to share a flash drive, but they cannot share an external hard drive?

I am recording Zoom meetings with my Windows machine and storing the videos on an external hard drive. I wanted to consolidate the folders by adding videos I have recorded on my Mac, but I realize I cannot just switch the external hard drive between the two machines.

Why is that possible when using a USB Flash Drive?

Should I then store the videos temporarily on a USB drive on one machine, and then use that to transfer the videos to a permanent external hard drive connected to another machine?

## microsoft excel – Text categorization with machine learning

I have excel sheets that contain written reviews of apartment complexes. Currently my team and I go through the reviews by hand and color code sentences by certain complaint categories. Ex. Noise, smoke, communication, maintenance, etc.

I would like to automate this process because for thousands of properties it is extremely time consuming to do every week.

I am asking for thoughts on how best to do this. I am wondering if it would be best to separate the reviews by sentence and then create a numbering system to classify each sentence. Ex. 1 for noise and 2 for smoke and so on. Then using some algorithm to try to classify the sentences.

Any input would be much appreciated because my background is not in machine learning or computer science. Thank you.

## Turing machine without return equivalent to Finite Automaton, PushDown Automaton or Turing Machine?

I have seen that a *Turing machine without return* is a Turing machine $M$ which at each stage of its calculation systematically moves its read / write head to the right.The aim of the exercise is to understand the computing power of Turing machines without return. If a language $L$ is recognise by a Turing machine without return, can we say that $L$ is also equivalent in recognising by a finite automaton, a pushdown automaton or by a Turing Machine? I would tend to say that the $L$ language can be recognized by a Turing machine with no return if and only if $L$ can be recognized by a pushdown automaton because the stack can simulate the movement to the right on tape of the Turing Machine.