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Posts posted by fiveworlds

  1. Quote

    If that includes an installation of Mac OS, you may be violating copyright by distributing it.

    Well I am not the distributor, it was uploaded by https://techsviewer.com If Apple wants to distribute a paid VM then I am happy to pay for it provided I isn't ridiculously expensive (I would pay $10 maximum). I am not going to carry two laptops around all the time and often have to use windows, mac, and Linux so VMs are the best option for me. I also like changing parts in my laptop and apple hate people doing that so I dunno am I willing to buy a mac computer when I can't mess with it but if they want to sell me a vm then I am happy to pay for it.

  2. Quote


    @fiveworlds, Are the halt() statements underneath that line supposed to be indented? Are they part of the function definition?

    Also is this a notation you made up? Or is it a standard notation for TMs that I could read about somewhere, and if so where?


    Nope you can use state transition tables too https://en.m.wikipedia.org/wiki/State_transition_table

    Yes the halt statements are part of the input tape n they don't need to be there though. I left it there to show that you can use multiple state transitions on a tape.


       :B(some Boolean expression)
      :C(some Boolean expression)
     :A(some Boolean expression)
      :halt(some Boolean expression)

    So for instance this TM has 3 possible states. It starts in tape A and accepts some input set which will only result in a move to state B if the Boolean expression is true etc. The :states symbols work the similar to basic goto statements in assembly with an if condition.

    For TMH we only stop executing if the string ":halt(some true Boolean expression)" is read by the TM or we run out of values to input from k.


    I know that your idea is wrong, simply based on the fact that everyone regards Turing's proof as perfectly valid.

    Who is everyone exactly?

  3. Quote

    you would become famous,

    I don't want to be though I like my privacy

    It is easy to show though we can define what you were suggesting which is a description of tape n like so

    input tape n = "
      :nextState(boolean function)
      :halt(input == toBin(":halt(true and true)")) ||
      :halt(input == toBin(":halt(true and not false)")) ||
      :halt(input == toBin(":halt(not false and true)")) ||
      :halt(input == toBin(":halt(true or true)")) ||
      :halt(input == toBin(":halt(true or false)")) ||
      :halt(input == toBin(":halt(not false or false)")) ||
      :halt(input == toBin(":halt(not true or false)")) ||
      :halt(input == toBin(":halt(not false or true)")) ||
      etc ||
      :stuck(input == toBin("end of tape")
    ) {
      Get next input from k check if it validates as a transition from
      state A if not get next input from k.
      If there is no more inputs in k then switch to state "stuck"
    HALT() {
      output "TM Halted"
    STUCK() {
      output "TM STUCK"
    inputTape k : ["input = 0000000", "input = etc"];

    As you can see from state A there is only certain inputs that will cause TMH to halt which are labelled with :halt.

    If input Tape k contains all the information in tape n then the input is too large to ever halt and will immediately become stuck.

    Tape n will only halt on inputs such as toBin("halt(true and true)") etc.

  4. Quote


    Assume there is a TM, call it TMH, that computes H(n,n). 

    Define another TM, called TMx, as follows. TMx(k) first runs TMH(k) to determine H(k,k). If H(k,k) = 1, meaning that the k-th TM halts on k, then TMx(k) goes into an infinite loop. 


    There's the problem it is an infinite loop. 

    You can however define TMH that computes H(n, k) where n is a Boolean Algebra and k is a binary input.

    Now I can encode TMH as n but not as k so the infinite loop never happens.


  5. I wouldn't be stressing over it anyway. Do you really need somebody in your life who would discard you over something trivial? He hasn't given you the option of making amends because he doesn't value you enough to even attempt to work out the situation. So why try? other people will respect you more if he thinks he can treat you as disposable and isn't going to apologize for his behaviour then just ignore him.

  6. Quote

    so even if it were possible/practical to extract the entire contents of memory and emulate the entire device (which I doubt)

    You just unsolder the memory chip from the board and place it onto a machine to copy it. Then you can solder the copied chip into the board. Strangeparts made a video about copying his iPhone data onto a new (much larger) memory chip. I don't know where you would buy the machine though. It is definitely possible.


  7. Quote

    But the specific thing about the windy postman problem is that the edges have a different cost depending which way you traverse them.

    Yeah the motorway going into the city can have much worse traffic in the morning than the motorway leaving the city.


    But I somehow suspect that someone who is working on multi-agent pathfinding is well aware of those problems and possible solutions.

    I would imagine so too. I am just pointing him in the direction of where he might find city pathfinding algorithms as opposed to A* which doesn't take traffic etc into account.

  8. Quote

    Can you explain how that is relevant. The OP didn't mention anything about asymmetry in the costs of traversing edges.

    The windy postman problem concerns finding the best route along directed graphs (think one-way roads) with a cost of travelling a road (think traffic and speed limit). It could be faster to take the motorway in the city than to take side roads etc even if the motorway route is longer.

  9. It is true though not exactly for why he says.

    Fat is required by the body for vitamin and mineral absorption, is needed to build muscle and should be approx. 20% of your daily calories. To lose weight you need to both keep your calories in check and gain muscle. To gain muscle you should be looking at following a weightlifting routine/cardio. Muscle will allow you to burn more calories throughout the day and keep the weight off the wrong advice of simply not eating/dieting will just cause you to lose muscle and to put all the weight back on when you start eating again and if you are getting older can lead to excess skin. You should aim to lose about a lb a week. If you don't lose a lb you are either eating to much or not working out hard enough.

    Stretching (Start of every day) - > Prevents injury and keeps flexibility

    Calf Stretch

    Quad Stretch

    Hamstring Stretch

    Groin Stretch

    It band Stretch

    Lower back Stretch

    Front Stretch

    Back shoulder Stretch

    Tricep Stretch

    Neck Stretch


    Impact (Start of every day) - > Helps bones absorb calcium prevents arthritis

    100 - skipping

    100 - heavy bag (punching/kicking)

    100 -  speed bag (punching/kicking)

    10 mins - trampoline


    Cardio - Treadmill (End of every day) - > Helps bones absorb calcium prevents arthritis of the legs and builds leg muscles / speed

    3-4 intervals of sprinting at the fastest speed you can for 3 minutes

    15 mins of fast walking at the highest incline you can manage 

    30 mins of jogging at least 7km or higher if you are able 


    Weights - Should be on rotation if you work your chest one day then do your legs the next and at the highest weight you can manage without losing form

    Monday - chest

    3 sets of 10 dips/weighted dips

    3 sets of 10  bench press

    3 sets of 10  seated military press

    3 sets of 10  chest press

    3 sets of 10 pressups

    3 sets of 10 pec deck


    Tuesday - arms

    3 sets of 10 lying cable curl

    3 sets of 10 bench dips

    3 sets of 10 barbell curls

    3 sets of 10  bicep curls

    3 sets of 10  tricep curls


    Wednesday - legs

    3 sets of 10 Squats

    3 sets of 10 leg curls

    3 sets of 10 lunges

    3 sets of 10 leg extension

    3 sets of 10 standing calf raises


    Thursday - shoulders

    3 sets of 10 lat pulldowns

    3 sets of 10 Standing barbell press

    3 sets of 10 side lateral raise

    3 sets of 10 upright barbell row


    Friday - back

    3 sets of 10 deadlifts

    3 sets of 10 pullups/assisted pullups

    3 sets of 10 single-arm dumbbell row

    3 sets of 10 close-grip pull down

    3 sets of 10 decline bench dumbbell over

  10. Quote

    Yes, it is possible to find the inverse of a 4 by 4 or 5 by 5 matrix (or a 100000 by 100000 matrix).

    Yeah if you have a good graphics card you should be able to run a 100000 by 100000 matrix reasonably quickly. 


    If no, why ?

    Modern graphics cards make use of parallelization for matrix multiplication therefore matrix calculations are extremely fast on modern computers provided you are making use of the graphics card.


  11. Quote

    If yes, how ?

    Train has schedule to depart at a certain time and then uses image recognition to ensure no passengers are too near the train prior to departing.

    That said I don't see them automated anytime soon not because it isn't possible but because people are unpredictable and it is safer to have a train driver and security than not have them.


  12. 48 minutes ago, kamenjar said:

    You mean the ship is not in between Earth and Proxima? The article didn't seem to say that.

    No I mean the article says you have a phone to call Proxima from earth. So why isn't there faster than light video communication too. One person could observe all the events happen in the correct order via faster than light video communication and no time travel would take place.

  13. Quote

    You are only supposed to have one outcome of an event. With FTL you could have more than one outcome.

    Where do you get that from?


    You have the call to Proxima. Let's say that call causes some event, which can only happen of there is a call. Then the callers on Earth get the signal not to place the call. They don't place it. And yet, the event has happened, even though the cause of it is absent.

    How can the callers on earth get the signal to place the call before placing the call?

    As I see it there are 4 main observers

    1-Earth, 2-Proxima, 3-Ship, 4-Universe.

    time moves relative to 1,2,3 as a factor of 4. eg. 1 second on earth could be 4 seconds on Proxima but 3 seconds relative to the universe.

    Relative to the universe the earth always makes the call first, then Proxima receives it,  the light travels a certain distance and then the ship observes the earth before the call is made, the ship then calls the earth to talk about the call to Proxima because it has already made the call.


  14. So let me know how you get on with the following tasks,

    Assignment 1:

    Part 1: Install java 10  http://www.oracle.com/technetwork/java/javase/downloads/index.html since it is the java version I am using right now and intellij idea it is the ide that I use https://www.jetbrains.com/idea/download

    Part 2: Create a java class to watch a directory for changes. To do so you will need to use https://docs.oracle.com/javase/tutorial/essential/io/notification.html

    Part 3: Install MySQL Workbench https://www.mysql.com/products/workbench/

    Part 4: Create a new database with a table containing just a Date column and an Event column in MySQL Workbench

    Part 5: Create a java class to make a MySQL database connection following https://www.tutorialspoint.com/jdbc/jdbc-sample-code.htm

    Part 6: Create a java class to keep track of the events from part 1 and save the changes to the database using the MySQL class you just created.

    Part 7: Create a .jar file from your java classes https://stackoverflow.com/questions/2025607/how-to-create-a-jar-file-or-export-jar-on-intellij-like-eclipse-java-archive-e

    Part 8: Create a .bat file to run the jar file you just created https://stackoverflow.com/questions/5774970/run-jar-file-in-command-prompt

    Part 9: Create a scheduled task to run your .bat file https://stackoverflow.com/questions/17438482/set-task-to-run-on-system-startup-schtasks-command-line

    Part 10: Restart your computer. Check that the task is running and delete the scheduled task from task scheduler

  15. Quote

    Pressurizing cabins is one thing, but where does the amount of oxygen consumed comes from ?

    The same compression used in the engine forces air through the cabin while the engine is running. If the engine is not running a chemical is used in the masks that drop from overhead.

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