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seen Jan 16 at 5:47

I am a dedicated Developer at heart coding and pushing my way to becoming a master.


Mar
5
comment Calculating the area of an irregular polygon
@joriki, I am still having some problem here understanding the Newton's method please. I get what you are trying to do but I still see R on both sides of the final equation that I am still missing. For instance, from what I see, you have initial value $R_0$, as well as $R_n$. What values are these for me?
Mar
5
comment How to work RSA encryption/decryption
I am not working with the bits or able to shift bits. Like I explained, I have an array with random numbers assigned to unique characters, and using that information, I need to encrypt my string. And then decrypt afterwards.
Mar
5
comment How to work RSA encryption/decryption
Thanks.I probably will end up breaking it up into bits. I thought it was possible to, looking at the algorithm for encrypting, I have above for encrypting all my string input at once, to come up with a way that will work for decrypting as well.
Mar
5
comment How to work RSA encryption/decryption
That is why I had it encoding my information one character at a time initially. If I have an input that hundreds of lines long, I still would like to be able to handle that without needing to keep looking for bigger and bigger prime numbers each time.
Mar
5
comment How to work RSA encryption/decryption
1. Initially set Ciphertext =1 2. For each character in the message string, I find the number key from my character table , and multiply it by the Ciphertext 3. Repeat step 2 until all of the characters in the message string has been handled. M=14891505242871484726569672376320000000000000 <=== Result 4. Encrypt the resulting Ciphertext ciphertext=230958 <== resulting Ciphertext
Mar
5
comment How to work RSA encryption/decryption
The problem is in mainly decoding the ciphertext so I can get back the code for the initial ciphertext at least. How do I get back M=14891505242871484726569672376320000000000000 from the ciphertext=230958. That is what I am having problems with, at the moment.
Mar
5
comment How to work RSA encryption/decryption
I have a table/array where each character has a number assigned. So whenever I look up the character in my array, I return the number that corresponds and then perform operations on the number that way. When I go to decode, I get the number, check the table for the character that corresponds to it and concatenate that to be decoded plaintext.
Mar
5
comment How to work RSA encryption/decryption
when I convert all my message at once, I get this cipher = 230958. How then do I decode this using my code above? That remains a problem.
Mar
5
comment How to work RSA encryption/decryption
I do have my encryption and decryption keys worked out. The problem is the how of encryption and then decryption the message input, I mean the algorithm for encryption 1 character at a time and then decryption to yield each character at a time.
Mar
5
comment Trying to calculate RSA decryption key
thanks for the tip.
Mar
5
comment Trying to calculate RSA decryption key
Here is the problem, when I put my Cipher through the same, I don't get the original back. $$106994^70643 (mod 239593)$$ in Wolfram also gives me $$152989$$, which is incorrect
Mar
5
comment Trying to calculate RSA decryption key
oops! I corrected that. Yes, it is and I get d=70643.
Mar
2
comment Calculating the area of an irregular polygon
@joriki, I am writing a program to do this(not much of a mathematician yet) but I hope that by coding some of the problems i have picked, I can get a better idea of what is out there. So, far, I have a solution for polygons <=4. I need a better explaination please of your Newton idea, since all I know is that I need to find R before I can find Area.
Mar
2
comment Calculating the area of an irregular polygon
Thanks. I did go ahead and implement the Brahmgupta solution to handle 3/4 sided polygons, but I still would prefer a solution that handles all edge counts.
Mar
2
comment Calculating the area of an irregular polygon
Thanks. What I was trying to do is figure out a formula for computing R from the first equation you have there in your answer. I figure if I can compute R by using the edges I have, I can then compute Area using the second approach as well.
Mar
1
comment Calculating the area of an irregular polygon
one more silly question . . . where do I get R from? :)
Mar
1
comment Calculating the area of an irregular polygon
I am not certain I follow. I don't know what R is and what does L(k) stand for?
Mar
1
comment Calculating the area of an irregular polygon
Yes, the irregular polygon is cyclic. But I am stuck on how to compute the area of the irregular cyclic polygon or the area of the contained triangles, given that for each of the (n-2) triangles in my polygon, I am only aware of the length of just two sides.
Sep
23
comment What language does the regular expression $c^\ast(a \cup (bc^\ast))^\ast$ generate?
Yes, I believe it is UNION
Sep
23
comment What language does the regular expression $c^\ast(a \cup (bc^\ast))^\ast$ generate?
You mean $(a\cup(bc^*))$ could not generate $ab , abc $ ?