Python Questions - July 25, 2015

[E.D.G.]

"E.D.G." <edgrsprj at ix.netcom.com> wrote in message 
news:jf6dnQiMOZ_GxC7InZ2dnUU7-S2dnZ2d at earthlink.com...

Posted by E.D.G.   July 26, 2015

        These are some additional comments related to my original post.

       The effort I have been discussing actually involves developing a 
totally free version of some language that scientists around the world could 
easily install and use.


1.  With my own science related Perl programs I provide people with .exe 
versions in addition to the .pl versions.  And for the .pl versions, at one 
of my Web sites there is actually an entire Perl programming language 
directory available in a .zip package.  So, people can download the file, 
unzip it, and then save it as the Perl directory and .pl programs will then 
run on that computer.  We would like to be able to do the same thing with 
Python if we start working with that language.  And a response in another 
post indicates that this should be possible.

2.  Python looks especially attractive because so many people are using it. 
And I myself have a friend who is a very experienced professional Python 
programmer.  On the other hand, there are so many versions of Python that it 
might be difficult at first to determine which one to start with.

3.  I asked that Python programmer if Python could run on an Internet server 
as a CGI program.  And the answer was "I have no idea."  So, amusingly, 
apparently even experienced professional programmers don't know everything 
there is to know about a given programming language!

4.  I myself know that Perl programs will run on Internet servers as CGI 
programs and have written several myself using a development program called 
Xampp to create and test them before installing them on the server computer.

5.  My retired professional programming colleague has now told me that he 
downloaded and installed the ActiveState Windows version of Python with no 
difficulties.  So, that is encouraging news.

6.  He said that he is looking around for a good IDE for Python and found 
one called "Eric" that he is checking.

7.  With my Perl language programs I have developed a resource that will do 
the following.  And I imagine that this could also be done with Python. 
This resource can't be developed with many and probably most programming 
languages.

       In part because of limited calculation speeds it can take one of my 
important probability calculation Perl programs as much a two hours to run 
and create all of the necessary data arrays.  Many, many millions of 
calculations are involved.  And once everything is set, for time limitation 
reasons it would be ordinarily be impossible to make any changes to the data 
or to the original program code without losing all of the data.

       So, I have developed a special Perl program that makes that possible. 
And as I said, I am guessing that this approach would also work with Python.

       When the Perl program is done with its calculations, instead of 
ending it jumps to another Perl program.  But all of the data in the arrays 
it created remain active in memory.  The original program code can then be 
changed.  The second Perl program is then told that the changes are complete 
and that it should return to the first program.  Perl then attempt to 
recompile the original code.  If it is successful it then uses the new code 
and does whatever is specified.  The previously created arrays are still 
active in memory using the same array names etc.

       If there was an error in the new code, a Windows screen appears 
explaining that there was an error and the compilation ends.  But, the data 
remain in the active computer memory.

       Changes can then be are made to the program code to fix the error. 
And, the second Perl program is told to try again.  If there are no new 
errors the first program recompiles and runs using the already created 
arrays etc.

      This is a very useful resource for scientists as it lets them create 
and test new program code without having to recreate all of the data arrays. 
And as I stated, it would probably not be possible to develop such a 
resource with most programming languages.

Regards,

E.D.G.