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The previous one was done with sticks, this one just makes it easier for the layman to understand.
"This perpetual motion machine she made is a joke. It just keeps going faster and faster. Lisa, get in here! In this house, we obey the laws of thermodynamics!" - Homer Simpson
Web - Blog - RSS - Math - LinkedIn - BM
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That looked like a whole lot of hard work to me... just do it the normal way and be done with it!!
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Don't walk in front of me, I may not follow;
Don't walk behind me, I may not lead;
Just bugger off and leave me alone!!
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I am not sure of an exact definition but as far as I am aware encoding is changing the way that the string is displayed, to mask it or change its format but is essentially in a fixed format and easily reversable. Encrypting masks the string with a key of some type (dependent on encryption type) and can usually be decrypted with the provided key.
Some encryption cannot be unencrypted, such as MD5, but the same encrypted string can be compared for validation - useful for passwords.
Not exactly a dictionary definition i know!
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I'll add that MD5 isn't considered a strong encryption algorithm these days.
"Any sort of work in VB6 is bound to provide several WTF moments." - Christian Graus
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Encoding a string has to do with its internal representation. For instance, UTF8 or UNICODE maybe different internal representations of the same string.
On the other hand, encryption aims to alter the string in such way that its original content is not recognizable by unauthorized people. Usually encryption imply encoding, usually encoding doens't imply encryption.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
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Hi,
encoding is the process of mapping a collection of some type1 onto a collection of some type2,
for instance you can encode the days of the week into the numbers 1 to 7; and the ASCII
character encoding maps the character set we all know to a subset of 8-bit numbers.
So it is a representation thing (a one-to-one mapping), often aiming at increasing
readability or efficiency.
encryption is the process of changing the representation in order to hide the content.
the goal is not to make things easier, smaller, more economical; it is to hide the true
meaning of things.
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Wikipedia man!!!
Mark
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Encrypting a file means that one is altering it in order to conceal its contents.
Encoding it means one is altering it because of technical reasons related to transmitting it (e.g., the Morse code).
Regards,
Satips.
Don't walk in front of me, I may not follow;
Don't walk behind me, I may not lead;
Walk beside me, and just be my friend. - Albert Camus
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Newton Rapheson ring a bell (Goal Seek function from Excel, that's the Algo they used)? Packaged bug free code anyone?
Thanks a bunch.
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You give no hint of what language you want, maybe Numerical Recipes is a good place to start - here is the 'c' version:
Newton-Raphson Method[^]
Peter
"Until the invention of the computer, the machine gun was the device that enabled humans to make the most mistakes in the smallest amount of time."
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right! Numerical Recipes! Left school for sometime totally forget about it!
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Excellent read.[^]
The PostScript file (year 2000) is more informative.
"This perpetual motion machine she made is a joke. It just keeps going faster and faster. Lisa, get in here! In this house, we obey the laws of thermodynamics!" - Homer Simpson
Web - Blog - RSS - Math - LinkedIn - BM
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"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon
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Regards,
Satips.
Don't walk in front of me, I may not follow;
Don't walk behind me, I may not lead;
Walk beside me, and just be my friend. - Albert Camus
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Great
Russell
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I have a set of X-Y-Z coordinate points defining a 3D space (actually contour data). Then supposing I want to find the elevation at point X-Y, would the following method work (or does anyone have any other, better, suggestions):
1) Flatten the XYZ data (i.e., take the X and Y coords)
2) Construct the 2D Delauney triangulation for the data set.
3) Find the triangle in which the point X-Y lies.
4) Use the XYZ coords of the vertices of the triangle to interpolate the elevation at XY.
Of course the hard part is 3, but is the principle sound?
Anyone know of any sample code I can refer to? (bearing in mind I'm not a mathematician or geometrician!)
Cheers
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Years ago when I did some work in this area we had data on a rectangular grid - made things easy
If you google on "gis interpolation" there are a lot of interesting hits,
Peter
"Until the invention of the computer, the machine gun was the device that enabled humans to make the most mistakes in the smallest amount of time."
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I need to retrieve the first four alphanumeric characters from a string, basically,
if I have "DE WINTER", I need to skip the third character and write "DEWI".
Other than going through each substring is there some algorithm for this pattern?
Jon
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It actually depends on the language you're using: string objects usually offer a suitable Replace method.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
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I'm using JavaScript.
Taking this point of view, the problem is that I need to iterate through each character in the source string and replace non-alphanumeric characters with a blank string ('').
Jon
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This http://www.w3schools.com/jsref/jsref_replace.asp[^]] doesn't help you, does it?
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
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Hiya
i am looking for algorithm for Steganography in .mp3 and .jpg....
I found few links while searching in google but all say something different...So any one here with a good algorithm for this task...
And yeh i want to implement it in C#.Net..Yeh i know there are many articles for stego in this site but they are not for .jpg or .mp3..
thanks
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Search CodeProject for it, you will find several articles.
And yes there are many ways to do it.
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I dont think there is any article for .mp3 and .jpg in code project...Thats what i mentioned in my post...
Yeah there could be many ways, just trying to know which algo is the best way if somebody has already achieved that...
anywayz...
Thanks
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