Algorithms beyond programming

[stereologist]

You're right. Typical FSM applications find the pieces of the input, but the relationships between those pieces. I misunderstood your post. Sorry about that.

[maddog]

Originally Posted by SidewalkCynic

I recently learned that algorithm is a word being used without a definite defintion, as seems to be the case of a lot of terms I have been analyzing.

Anyway, I am wondering about this passage that algorithms and it seemingly exercised in fields beyond computer programming.


There is no reference, anybody able to direct me toward any?

You have everything you need in the Wiki definition of Algorithm to answer your question.
If this is not enough to be satisfactory, look up Buffy's post #9 in this thread. Enuff' said.

maddog

[maddog]

Originally Posted by Pyrotex

I've been programming for 30+ years, and I have to agree with the above.
An algorithm is a specific set of instructions that, when executed, will result in a specific end-state or solution.
An algorithm may be expressed in technical English; when it is expressed in a specific computer language, it is often called a "routine" or "program" or "script".
The description of what the algorithm is supposed to accomplish, under all expected conditions, is the
"set of requirements" or the "specifications".
The general term for creating algorithms is "coding", especially if the algorithm is being created in a specific computer language. If it's being created in technical English, it is sometimes called "pseudo-coding".
Algorithm has many synonyms, such as recipe, instructions, procedure, process, especially when used in a non-computer context.

Pyrotex,

You may have a year or so on me. I agree with you on all you said with one point
which I have highlighted. No that I disagree with it. It is just that Buffy's example in
post #9 constitutes an algorithm by even your definition with the last statement in
essence
"got to step 1" or repeat.
This is in a sense a terminating case that just starts over.

maddog

[maddog]

Originally Posted by stereologist

The stopping criteria is part of the definition used in the theory of algorithms. Here is the Wikipedia page.
Algorithm - Wikipedia, the free encyclopedia

It says "eventually terminating in an end-state".

An infinite loop as mentioned several times here is not an algorithm. It may be a program, but not an algorithm.

I was looking at that Wiki article. You also forgot to mention one other statement in the
same article, under the heading Termination.

Some writers restrict the definition of algorithm to procedures that eventually finish.

Which implies that some do not. This could construe that Algorithm includes both
interpretations: "to endless loop or not to endless loop, that is the question."



maddog

[maddog]

Originally Posted by stereologist

Still, the issue of termination is an important consideration in the definition of algorithm. Otherwise, it would not have been discussed.
Since all books I've used on the subject of algorithms include termination as a part of the algorithm definition I suspect that allowing nonterminating procedures to be part of algorithms makes the definition not useful.
As Minsky pointed out, if you don't know what the answer is, then what do you do.

Consider the embedded code with the modern Microwave. It basically functions until you
turn it off, the power goes out or you find some way to reset it (funny button in the back).
The algorithm here takes each button press and processes it according to some preset set
of rules which were encoded. So any termination here is nonstandard. Yes it is a program also.
As Pyrotex said earlier, Algorithms are often expressed in "psuedo-code". Termination is
not always the focus. Some people restrict algorithms to require an end-state, Not All.

maddog

[maddog]

Originally Posted by stereologist

To be honest no. It is provable that there is no finite decimal expansion for pi or sqrt(2). So no algorithm can be written that computes these values.

What's wrong with process, procedure, computation, method, technique, method, routine, or operation?

What if I define an "algrorithm" for computing to arbitrary precision.
If I were to set that "precision" to be "exact" and I could continue computing to that
precision, my "algorithm" would terminate.
Periodically it produces output of successive answers. Does this program not ending (if I
choose), make the algorithm that designed it "not an algorithm" ???
This is often the practice at various Scientific Computing Centers around the world that in
their "idle time" they compute Primes. It is useful and it never ends (there is always more
primes). It is the operating system that suspend this task at the end of its time slice
to run other tasks.

Sometime the "answer" is not at the "end of the journey", it is getting there or the "journey"
itself.

maddog

[maddog]

Originally Posted by stereologist

The term parse as you use it Pyrotex is incorrect. To parse is to identify the relationship between the words or parts of a sentence. A parser accepts and rejects input.

The FSM is an automaton that is capable of parsing what are known as linear grammars. These are simple grammars. Push down automatons are required for the next level of grammar complexity called the context free grammars.

I'm not surprised that you have not heard parse used correctly. It rarely is.

Another example of the misuse of language is found in a company where they told people to "solution the problem." No one solved problems there. I always imagined the bosses stirring large vats of liquid trying to create solutions.

I believe that Pyrotex was using the definition of "parse" as similar to that in Wiki
Parsing - Wikipedia, the free encyclopedia
which would be my definition as well.
I was recently using C# code where I was needing to get IP address from a string as
"192.168.13.4". Microsofts DotNet has a neat feature called Parse that will decode this
address into a C# simple type as long.

maddog

[stereologist]

Just because MS also misuses the term parse does not mean anything. MS is notorious for doing things their way. And I am familiar with lots of instances of the misuse of the term parse. And you admit you misuse the term parse and that is par for the course.

[stereologist]

As far as algorithm goes, you mention things such as finding primes. I suggest that each instance of finding a prime is an algorithm. The non-ending loop is not an algorithm.

I also suggest that you be wary of the Wiki. It has no more correctness than this forum.

[maddog]

Originally Posted by stereologist

Just because MS also misuses the term parse does not mean anything. MS is notorious for doing things their way. And I am familiar with lots of instances of the misuse of the term parse. And you admit you misuse the term parse and that is par for the course.

I will agree that MS does far short of the mark as reputable as to correctness of terms and
such.

I admitted to "misuse" of the term "parse" ? When.

Aren't we talking "context" here...

maddog