khaled
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Posts posted by khaled
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matter can neither be created nor destroyed...think about that
I think you confused Matter with Energy
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Java:
public class Ternary { private String num ; public Ternary ( ) { num = "0" ; } public Ternary ( String n ) { num = n; } public void set ( String n ) { num = n; } public String get ( ) { return new String ( num ) ; } public parseDecimal ( int d ) { num = "" ; if ( d == 0 ) { num = "0" ; } int m = 1, b = 3 ; while ( d > 0 ) { num += ((d%10)*(b^m)) ; m++ ; d /= 10 ; } } }0 -
that's history, in the future we will have a city of data centers in the size of your hand palm
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I think mister Dekan have done something wrong in his earlier argument, By using real numbers in a discrete way,
I think he should've used the set of natural numbers,
which is basically the set of all positive integers that are greater than 0
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I forgot to mention that data storage units (traditional architecture) in computers are [in ascending order for access speed, and descending order for cost]:
- Registers (highest access speed, most expensive)
- RAM
- Cache
- ROM
- Hard disk (SATA, Solid State, ..)
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Yes,I do agree,but they programme themself ,here in claytronics scientists use static force of attraction and softwares to program them.I agree with CaptainPanic, Computer scientists build models that approximate the systems of ants, bees, ..etc
models that approximate, but are never the exact .. in-between Soundness and Abstractness
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I think a proper answer is to understand .. now any data is encoded using a standard such as ASCII, UNICODE, ..etc
at the low level, all data are just series of binary digits (0s and 1s),
0 and 1 are represented in the physical level as two levels of electric charge (current computer models),
which may change in the future to different quantum states (Quantum Computer)
To study all about computer and technological hardware (including microchips)
.. you need to study Computer Engineering, which includes advanced mathematics and physics
good luck
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If you are a bachelor degree I think you will most likely study Calculus, Probability & Statistics (Intro), Linear Algebra, and Discrete Mathematics
If you are master degree I think there'd be Probability & Statistics, Multivariable Calculus, Real Analysis,
Advanced Discrete Mathematics .. and maybe others
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The Open MIT courses are great
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A couple years ago I got in a fight, I got a boxers fracture on my right ring finger and right pinkie. They didn't heal properly, and I don't have very good control over them. Is computer science still a possible career for me? How fast are you required to type in a computer science career?
First you have to calm down, your chances with Computer Science are still the same
in Computer Science studies, it doesn't matter how fast you type on a keyboard
by the way, have you ever heard about those who type using only 1 finger of each hand, some are pretty fast as far as I know
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guys what is the difference between html and javascript, i find both of them similar in may regards
HTML is a markup language that is used to build web pages for internet clients, Java Script is a Client-side script
in HTML you design how the web page looks like to the client
in Java Script you can do some simple programming
.. and you can use both inside HTML page, like this example:
<html> <head> <title>HTML\Java Script Example</title> <script> // Java Script Code var Hi = function ( ) { return "Hi" ; }; </script> </head> <body> <p> <script> document.write( Hi ( ) ) ; </script> </p> </body> </html>0 -
I'm not good in Networks, but I think you should learn more about the philosophy of Network models and the Internet
Because Computer Networks are built based on concepts such as Layering Concept (a concealed layer that offer services), Encapsulation
Concept (information are manipulated directly only through inside methods), Communication Theory (how humans communicate and its
randomness), Entropy Theory, Entity Independence Philosophy (building a system where every entity have independency "that it can functions
even when it's alone"), and the concept of mono-module entities (something is built just for one single job, in a system of these entities
maintenance, performance, and effectiveness can be high).
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So, what I'm trying to say is, one should understand the ideas behind the technical details of these systems, instead of trying to
improve these systems from the technical side which might break its philosophy.
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So, here is a simple way to try .. Try to design a method so that a group of humans can communicate in an effective way
-- Good Luck
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I can tell you the hard way to build a Java app with a User Interface, through writing codes
The easy way I use to build Java app with a UI, is using Netbeans IDE the Java SE edition
It's very simple, just follow the steps in the pictures:
Step 1: Launch Netbeans IDE
Step 2: File > New Project
Step 3: Categories:Java > Projects:Java Desktop Application
Step 4: Design your interface using drag-and-drop, and link them using the code
Note: the last snapshot is from a project I've finished, in the picture you can see JTable (Java Table UI component)
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I think that Energy is like money, an object spend for a work to be done .. that's how I understand it
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Our discussion was about the Offline Bootstrap, which is a part of an installed OS
There is a different type known as Network Bootstrap, which is a Live System Core that is loaded from a server, to start up the device
the reason for that is because this OS doesn't operate any regular device, but actually it operates your thin-client, which in fact
works on a super computer (or Cluster) connected through network
this type is usually used with Terminals and Light-Clients, sometimes used for Super Computing gates, and Factories terminals
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Your logic is wrong here; you've already assumed that a exists to make this statement.
=Uncool-
I'm not good in proof, but I know that [math]a \in \mathbb{R}^+ \;\;\rightarrow\;\; \sqrt{a} \in \mathbb{R}^+[/math] is True
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You're right .. It seems that time is one big question, I've heard many things from media, some:
- "in a timeless reality, where 'beginning' and 'end' are meaningless" --Final Fantasy XIII-2 (Game)
- "Observers, they exist at all times simultaneously" --Fringe (TV Series)
- "What is Eternity ? Define Time." --unknown scientific quote
- "Imagine humans are swimming through the river of time, Imagine there is someone who is watching on the riverside." --unknown
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Earth is not a perfect sphere, but rather a spheroid .. where lands at northern & southern pole are semi-flat
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Time is simple
Let's say we have a particle,
If it's timeless, then it just have a position in space (x,y,z), which is the same at all times
Otherwise, it has a position (x,y,z, t), which means that at time t its position in space is (x,y,z)
You can see from the second line, that particles bound with time, can have two different positions in space at two different times, this show progress
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Ok connector let's try this with Logic,
[math]a \in \mathbb{R}^+, b \in \mathbb{R}^+[/math] :
Your proposition (A): [math]\sqrt{2}[/math] does not exist
We know this is true (B): [math]2 \;\; exist[/math]
[math]IF \; b = (a \times a) \; AND \; b \; exist \; THEN \; (a \times a) \; exist \; \rightarrow \; a \; exist \; \rightarrow \; \sqrt{b} \; exist[/math]
Note that in the above statement: [math]a \times a =b \; \rightarrow \; a^2 = b \; \rightarrow \; b^{1/2} = a \; \rightarrow \; \sqrt{b} = a[/math]
Now, let's try [math]b = 2[/math],
[math]IF \; 2 = (a \times a) \; AND \; 2 \; exist \; THEN \; (a \times a) \; exist \; \rightarrow \; a \; exist \; \rightarrow \; \sqrt{2} \; exist[/math]
If you don't want to use the notion [math]\sqrt{2}[/math] .. you can just use this [math]{2}^{1/2}[/math]
It's clear "from the above statement" that your proposition (A) contradicts with truth (B)
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3. I didn't say that NSP is NP-hard, I said scheduling problems are NP-Hard, they can be reduced to CSP\SAT
The most basic NP problem is Binary-SAT, so scheduling problems that has at least 2 basic constraints are NP-Hard
If there exist a scheduling problem that has 1 basic constraint, or no constraints .. these two variations are not NP
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1. My citation was from Wikipedia, not from Literature
2. The word "Nurse" in NSP, is like "Salesman" in TSP .. they are just a name, each of these problems are just variations of the same problem
and my speak earlier was general about scheduling problems (variations of NSP).
3. I didn't say that NSP is NP-hard, I said scheduling problems are NP-Hard, they can be reduced to CSP\SAT
we just consider them nurses, they can be anything else, with any other constraints .. finding a solution forscheduling problem might sound simple if you try it on paper, but it's not easy for a computer to solve
the changing of constraints is non-trivial - in fact it is crucial; there is also the matter of minor and major constraints, which this problem does not deal with.
-- I was talking about the intractability of scheduling problems, not the scheduling constraints
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Khaled.
This is not the nurse scheduling problem.
At the easiest, everyone is available for every shift, and so finding a solution is very simple.
At the hardest, it closely resembles the nurse scheduling problem, and so finding a solution would be roughly equivalent and take about the same amount of time.
Is it that you disagree with me, or won't go read the references .. what I wrote in my reply is no opinion,
A problem is not P or NP, intractable or tractable based on what we think .. NSP is like any scheduling problem,
we just consider them nurses, they can be anything else, with any other constraints .. finding a solution for
scheduling problem might sound simple if you try it on paper, but it's not easy for a computer to solve
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Both P and NP problems are decidable problems which means that there exist algorithms which can check whether the given inputs satisfy the constraints or not. There is a lot of difference between checking whether a number is an armstrong number or not and generating a series of armstrong numbers say from 1 to 1000.
Halting problem is classified as an undecidable problem for which there is no algorithm to check whether a given input and a program halts or runs forever.
It's a huge confusion actually,
Verification: check if there exist at least 1 solution for the given problem.
Check: check if the input is a valid solution for the given problem.
It's just like the difference between "are there BLUE balls in the box ?" and "is this a BLUE ball ?", where the given
problem is "get a BLUE ball from the box".
Decidability: A language is called decidable if there exists a method - any method at all - to determine
whether a given word belongs to that language or not. --Wikipedia
Actually decidability is not a simple concept, I know the concept but I don't understand it that I don't have enough understanding,
Halting problem is undecidable, but it is partial-decidable.
In Algorithms, decidability can be simple as deciding weather the input is a solution to the given problem, just like the example
you gave of armstrong numbers, or can be complex as deciding weather an input is a member of the set of solutions for the given
problem, which can be described in a different way to Turing Machine, saying is the state that this solution ends with exist in the set
of final states F ...
a polynomial is an equation of the form n^a +n^(a-1) +n^(a-2)... n^3 +n^2 +n +1 where n is the size of the input.
to say a problem is bounded by a polynomial, generally means it's an "easy" problem.
the most common example i can think of would be sorting.
say you have a list of values of unknown magnitude (they can be as big or as small as desired) and you want to place them from smallest (closest to -infinity) to largest (closest to +infinity) there are many approaches to solving this problem, at worst it takes n^2 time, where n is the number of values, and at best it takes n*log(n). both are considered polynomial times.
to say a problem is non-polynomial, generally means it's a "hard" problem.
the classic non-polynomial time algorithm is the traveling salesman problem.
imagine you have a bunch of cities each with one or more connecting roads. is it possible to visit every city only once, without going back over the same road?
this sounds easy to solve, but is actually quite hard. with enough cities and enough roads, it could literally be "impossible" (take a very long time to determine).
the good news is, with most problems that are non-polynomial, once you have an answer, generally its fairly "easy" (polynomial time) to check if you're right.
It's not about how much time we need to solve a problem with 10 cities for example, it's the question of how the algorithm progress with input increase
[math]P[/math] denote algorithms that are polynomial-time bounded, in other words: [math]O(Time(\alpha)) \leq O(n^c) \;\;\rightarrow\;\; \alpha \;is\;P[/math]
where c is a constant, n is the size of input.
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Polynomial division is dangerous!
in Analysis and Calculus
Posted
I agree with BigNose, actually higher numeric variable precision than the standard are possible, and if you do arithmetic operations over them,
unlike standard ones that would work directly on on the ALU itself, they will be done on a virtual dynamic ALU that can work on any numeric precision
but based on that precision, there will a price to pay on the side of processing power needed