🌐 Mailman 3 April 2006 - Python-list - python.org

Application Generators
by walterbyrd July 21, 2006

July 21, 2006

I would like to put together a very simple inventory program. When I ship an item, and edit the quantity; I would like the quantity _on_hand to auto-decrement, and the quantity_to_reorder to auto-increment. Also, when the data is displayed in a table format, I would like to be able to edit the quantity field as I would in a spreadsheet, just edit that field, without having to change to an edit-record screen. I thought the easiest way to do this would be to use a PHP code generator. But I'm not having any luck. Maybe I give up and code by hand? Or maybe I should use django? It seems that application generators never do exactly what you want, and even if they do, what about future development? I am looking for something that will make it easy to put together this simple project, and be flexible enough that I can easily modify the project. This application is supposed to run on hosted server, so that is also a concern. The present host doesn't even have python, but I could move the site to a new host, which has cgi python. I have an open mind. If anybody can suggest anything, I will take a look. Application generators that I have tried: dbQwikSite: I found it difficult to get it to work, and very slow. I had to uninstall Xampp, and install AppServ just to get it to work at all. I don't know why, maybe Xampp's versions of php/mysql were too new? I still can not get it to generate php code that I can use. AppGini: works as advertised, easy to use, inexpensive, and fast. But, frankly, it doesn't do much. As far as I could see, it doesn't even offer the basic security of a login. It just displays data, and allows you to add/delete records. I don't even think you can interactively edit records. Not much reporting capability. PHP-Runner: the best so far. Fast, easy, nice looking display, has basic security, allows editing records. Still does not seem to have the basic functionallity I'm looking for. Other app generators that I have looked at, but not tried: PHP-Peanuts PHPMaker phpmysql DaDaBik WizzyWeb Navicat Again, glad to read any opinions.

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perspective on ruby
by RK June 28, 2006

June 28, 2006

I apologize if this is a stupid question, I'm asking Python group for perspective on Ruby, but I don't see how the alternative of going to a ruby group for a perspective on Ruby is going to do me any good... I just unpacked and tried out InstantRails, after turning off the local Plone stack. Looking over the IR stack, making the required hacks to the examples, looking at all it's pieces(including some of the more powerful PHP support mixed in), looking at the shipped examples, I had to marvel again at how far behind these folks are compared to something like Zope. They are 10 years behind an integrated platform like that. I just don't get it. The scripted object-oriented clean programming language is done. I'm more than willing to supprt RoR if it's being sold as the popular alternative to .NET programming, which it is in some CS curriculum (where Java being thrown out). But, all those "END"s are getting on my nerves. Thx

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Earthquake Forecasting Program July 11, 2005
by edgrsprj June 14, 2006

June 14, 2006

PROPOSED EARTHQUAKE FORECASTING COMPUTER PROGRAM DEVELOPMENT EFFORT Posted July 11, 2005 My main earthquake forecasting Web page is: http://www.freewebz.com/eq-forecasting/Data.html Newsgroup Readers: If you circulate copies of this report to groups of computer programmers at different universities etc. around the world then they might find the subject matter to be interesting. The information in this report represents expressions of personal opinion. THE GOAL OF THIS REPORT This is part of an effort to get some idea regarding how many computer programmers and other researchers around the world might be interested in participating in a project aimed at developing life saving earthquake forecasting computer programs. That effort is not presently underway. And I don't know when or if it will get started. I am simply attempting to determine if other people believe that large numbers of volunteers would be interested in working on such a project or if there would instead be little interest in it. That information would be helpful for developing a plan for establishing a Web site where the project would be centered. Personnel running the following Web site have volunteered to make their site available for such an effort. But nothing has gotten underway so far. http://www.ictwhoiswho.net/comprend/index.cfm If quite a few people were interested in such a Web site based computer program development effort then after it got started work would undoubtedly progress quite rapidly. If only a few were interested then it might never get started. If you would like to express an opinion on the likelihood of people being interested in the idea then you can try posting a note in response to this one. The sci.geo.earthquakes or comp.lang.misc newsgroups might be appropriate if you wish to post to just one newsgroup. Of you can try contacting me by e-mail. THE CORE OF THE PRESENT EARTHQUAKE FORECASTING PROGRAM In connection with an earthquake forecasting effort which has been underway for the past 15 years I believe I have been able to crack the "Earthquake Code." That means making crucially important discoveries regarding how earthquakes are being triggered. Two of them which are discussed on the following Web page are called the "Gravity Point" and "Earthquake Triggering Symmetry." http://www.freewebz.com/eq-forecasting/90-05.html The earthquake triggering and forecasting theories and data on that Web page were discussed on my behalf by one of my research colleagues in the People's Republic of China at a disaster mitigation conference in that country in December of 2003. Governments and disaster mitigation groups around the world were told about the Web site earlier this year. And my Web site visitor counter indicates that some 100 to 200 people around the world are presently downloading information from the site each day. My earthquake forecasting computer programs use those Gravity Point and Earthquake Triggering Symmetry discoveries and others to compare electromagnetic energy field fluctuation type signals (EM signals) with more than 30,000 earthquakes which occurred since the beginning of 1990. Some 100 to 200 signals detected during a 3 month period of time are involved. For some as yet unknown reason they are often highly selective for earthquakes which are likely to occur near populated areas, making them unusually valuable. The earthquake which is the best match with all of those signals is rated # 1. The worst match would have a rating number greater than 30,000. A listing of more than 100 of the best matches is then posted perhaps once a week to the following Web page: http://www.freewebz.com/eq-forecasting/Data.html For a recent example of how well that approach to forecasting earthquakes can work, data displayed on that Web page on June 27, 2005 gave the following earthquake a # 3 rating (possible rating range: 1 to 30,000+): 2005/01/11 19:19:48 11.40N 86.51W 40.7 5.0 Near the Coast of Nicaragua (U.S. National Earthquake Information Service data) And less than a week later on July 2, 2005 the following powerful and strongly felt earthquake occurred: 2005/07/02 02:16:46 11.18N 86.40W 45.5 6.7 Near the Coast of Nicaragua 11.40N and 86.51W versus 11.18N and 86.40W Pretty good accuracy for a forecasting program! That earthquake was reportedly strongly felt in Managua. Had it occurred directly beneath the city and near the surface then I expect that it would have been devastating. WHAT NEEDS TO BE DONE Basically, more sophisticated data processing and data display computer program subroutines need to be developed. They could be built on my already existing computer programs and data. People would develop new subroutines, give them a try, and see if they did a better job of determining or displaying where an earthquake might be about to occur. The subroutines could be stored at the proposed Web site. Ones that were especially helpful could be merged into the main program one version of which might run as a CGI program at the Web site. Other versions of the programs would be downloadable for free for use on personal computers. The basic form of the data processing routine for my existing program and probably many other earthquake forecasting programs might be expressed in the following manner: Prob = aA + bB + cC + dD + eE + ... "Prob" is the probability that an earthquake of a given magnitude will occur at a specific latitude, longitude, depth, and time. A, B, C, D, and E . are things such as: A - the gradual buildup of strain in a fault zone due to the movement of the Earth's tectonic plates relative to one another B - temporary strain added to the fault zone by bending, stretching, and compression forces related to the Solid Earth Tide. (The ground shifts a little in response to the sun and moon gravities just as ocean water does - hence the Solid Earth Tide) C - temporary strain added to the fault zone by the weight of ocean water shifting from one location to another in connection with ocean tides a, b, c, d, and e .. are "weight" factors which specify how important A, B, and C etc. are at different points in time. "A," the gradual buildup of strain in a fault zone related to tectonic plate movement etc. is undoubtedly the most important factor and perhaps the only one which scientists around the world are in agreement on. It can probably be determined with a certain amount of accuracy for some fault zones at the present time, but not too many. With my present computer programs I do not use actual values for "A" as they would be impossible to determine. Instead when a strong EM signal is detected I simply assume that a fault zone somewhere has stored enough strain energy that it is about ready to fracture. And an effort is made to determine where it is located. With each probability calculation my present computer programs do about 30 separate comparisons between each of the 100 to 200 EM signals and the more than 30,000 earthquakes in my database file. The comparisons involve things such as the positions of the sun and the moon in the sky and the locations of ocean and Solid Earth Tide crests and troughs around the world when the EM signal was detected and when the earthquake occurred. For an example of one possible and relatively easy computer program improvement, an effort could be made to see if factoring in earthquake fault zone orientation - north and south versus east and west - improved the probability calculations. Another improvement would involve determining the importance of the latitudes of the Gravity Points and the sublunar points. At the present time only their longitudes are used in my calculations. (The sublunar point is the location on the surface of the Earth which a line drawn between the center of the Earth and the center of the moon would pass through.) An earthquake forecasting group at Madras University in India has already developed some advanced earthquake location determination routines which it appears might be helpful to this effort. Routines developed for use at the following Web sites might also be helpful. http://pasadena.wr.usgs.gov/step/ http://www-aig.jpl.nasa.gov/public/dus/quakesim/ THE PROGRAMMING LANGUAGE IN PRESENT USE The original programs were written in a number of languages including Basic. The main program is presently written in Perl. That language was chosen because it is fast and powerful, the compiler can be downloaded for free by anyone, and because it looks like it is getting sufficient support that calculations can be trusted and it will be around for a while. There is another feature of that language which I am guessing many other programming languages probably presently offer though that was not the case in the past. That is the ability to make changes to the program code itself at the same time that the program is running. I myself do that in the following manner: Ordinarily the main program "P1" starts running and performs a group of calculations. That takes about 5 minutes. It then waits for a keyboard instruction telling it how the output data should be displayed. As with probably any program, once it is running in the normal mode no changes can be made to the program itself. However when it is run in the following experimental mode that rule does not apply. A short program I will call "P2" starts running and immediately uses a "do" statement to get the regular program P1 to compile and start running. P1 does the original calculations like normal. But instead of waiting for the operator to enter a data display command it exits and P2 becomes active again. A display instruction is entered and P1 is told to recompile and start running again. Instead of doing all of the calculations from scratch it jumps strait to the display routine and uses the entered command to begin printing the output data. The data generated when it originally did the calculations are still in memory. The advantage here is that at any time, program P1 can be called into a text editor, modified as desired, and then saved. A new display subroutine can be added to it or an existing routine can be modified while the previously generated data are still active in the computer. Then when P1 is directed by P2 to recompile (that takes about a second) and run, the new subroutine is included just as if it were in the original program. If the compiler encounters a programming error it terminates and returns control to program P2. A correction can then be made to the new program code and the sequence repeated. No data are lost because of the error. And you don't have to wait for 5 minutes while the program recalculates everything. Data processing and display routines could be written with other programming languages besides Perl. If done with sufficient care more than one language could be used at the same time. The different language routines would simply be linked with one another. A LIFE SAVING EFFORT It appears to me (sadly) that few governments have a very good sense of direction with regard to the development of life saving earthquake forecasting programs. The work is usually undertaken by independent research groups at various government agencies or universities. They go their own ways, uninterested in or unable to work with one another to effectively forecast deadly earthquakes. They often claim that if they share information then they could lose their patent rights and potential profits etc. And that could actually happen. But isn't saving tens of thousands of lives more important than simply making a meager profit (which no one that I am aware of is presently able to do with their forecasting programs anyway)? I myself presently own 3 U.S. copyrights related to my forecasting technology. But I have been letting interested parties around the world use it for free. See: http://www.freewebz.com/eq-forecasting/301.html One country where forecasting program information is shared to some extent is the People's Republic of China were some 10,000 people reportedly work full-time in a state sponsored earthquake forecasting program. They are also supported by a small army of volunteer workers. But even there the forecasting efforts of different groups are not effectively coordinated very often from what I can see. And advanced forecasting technology being developed in other countries is frequently ignored. A listing of some other earthquake forecasting programs around the world can be found on the following Web page: http://www.freewebz.com/eq-forecasting/141.html A book discussing one of the forecasting programs listed on that Web page is scheduled for release some time in late 2005. See: http://www.sentientpublications.com/catalog/earthquakes.php I myself assisted with that effort by providing the author with some free technical information and book content advice. The proposed Internet Web site effort to develop an effective earthquake forecasting program discussed in this present report could not be ignored by governments around the world. Once they saw how well the programs worked then they would be forced to begin using them to predict their own earthquakes. United Nations personnel appeared to like this concept when I formally proposed it to them in July of 2004. http://www.unisdr.org/wcdr-dialogue/t3-dialogue.htm#34 And they discussed it repeatedly in their summary reports of the ideas proposed during that Internet Web site based conference. But no governments or disaster mitigation groups expressed any interest in developing the concept. Since the starting point for the proposed forecasting program development efforts would be the computer programs that I already have running, success would be guaranteed. So, the important question would then be, "How many computer programmers and other researchers would be interested in helping with such an effort?" This type of work is quite interesting and exciting when you become actively involved with it. You can generate a forecast. And then when the earthquake occurs where you expected you can get a pretty good shock. If the earthquake is also destructive the experience can be rather frightening. The importance of the work should be obvious. More than a quarter of million people reportedly perished in connection with the December 26, 2004 earthquake generated tsunami (tidal wave) in the Indian Ocean. My present forecasting computer programs did not become operational until several weeks after it occurred. But when I ran my EM signal data from around that time through the programs the results indicated to me that the earthquake could have been predicted. Why devote valuable free time to developing computer programs which do ordinary things when that time could be devoted to developing programs which might eventually help save tens or even hundreds of thousands of lives?

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Xah's Edu Corner: Criticism vs Constructive Criticism
by Xah Lee May 24, 2006

May 24, 2006

Criticism versus Constructive Criticism Xah Lee, 2003-01 A lot intelligent people are rather confused about criticism, especially in our “free-speech” free-for-all internet age. When they say “constructive criticisms are welcome” they mostly mean “bitching and complaints not welcome”. Rarely do people actually mean that “criticism without suggestion of possible solutions are not welcome” or “impolite criticism not welcome”. Such discernment is important. Wanton bitching as internet-using geeks are used to is not criticism is any form. People can be respected and make a living out of criticisms, called critics, but not bitching. And when one really value opinions, you often want criticism without qualifications. Just be happy that valuable criticisms may come to you free from the experts in the public. The instant you qualify what kind of feedback are welcome, your feedback is compromised. (this is particularly so for political or controversial subjects) One easy way for many of the unix geeks to understand this is the cryptology industry. If one really desires valuable criticisms that is polite or with solutions or “constructive” (whatever that means), one usually have to pay. ---- This post is archived at: http://xahlee.org/UnixResource_dir/writ/criticism.html Xah xah(a)xahlee.org ∑ http://xahlee.org/

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Pyrex installation on windows XP: step-by-step guide
by Julien Fiore May 22, 2006

May 22, 2006

Do you wand to install Pyrex on Windows ? Here is a step-by-step guide explaining: A) how to install Pyrex on Windows XP. B) how to compile a Pyrex module. Julien Fiore, U. of Geneva ------------------------------------------- ### A) Pyrex installation on Windows XP ### # step A.1 # Install Python (we used version 2.4.2) # step A.2 # Run the windows installer for Pyrex (e.g. Pyrex-0.9.3.1.win32.exe), available on the Pyrex homepage (http://www.cosc.canterbury.ac.nz/~greg/python/Pyrex/) # step A.3 # Install Mingw, the gcc compiler for Windows, available at http://www.mingw.org/download.shtml. (we downloaded the file MinGW-5.0.2.exe and installed only the "base tool" (this includes mingw-runtime 3.9, w32api-3.6, binutils 2.15.91 and gcc-core 3.4.2). Add Mingw path ("C:\MinGW\bin") to the Windows "Path" environment variable. If you already have cygwin installed, add C:\MinGW\bin before the Cygwin path. # step A.4 # Create or edit the file "c:/Python2x/Lib/distutils/distutils.cfg" and put the following into it: [build] compiler = mingw32 ------------------------------------------- ### B) Create a Pyrex module ### # step B.1 # Create a working directory (e.g. D:\pyrex_module\). Write a pyrex module and save it with a "pyx" extension (e.g. "primes.pyx", code available on the Pyrex homepage) # step B.2 # Write the following python script and save it as "setup.py" in your working directory. from distutils.core import setup from distutils.extension import Extension from Pyrex.Distutils import build_ext setup( name = "PyrexGuide", ext_modules=[ Extension("primes", ["primes.pyx"]) ], cmdclass = {'build_ext': build_ext} ) If you want to compile several modules, duplicate the line starting with "Extension" and replace "primes" by your module names. # step B.3 # In your working directory, create a batch file called "build_and_install.bat" containing the following lines, where "PythonXX" should be replaces by your Python version (e.g. "Python24"). C:\Python24\python.exe setup.py build_ext install pause To run the batch, double-click the file. You will see many "Warning" messages during the building process: do not worry, it is normal. # step B.4 # Mission completed. The file "primes.pyd" (a "pyd" is a Python Extension DLL, equivalent of .so in Unix) is now located in "C:\Python24\Lib\site-packages" and the "primes" module is available in Python. In your working directory, you can delete the file "primes.c" and the "build" folder created by the building process. Test your new module at the python shell: >>> import primes >>> primes.primes(10) [2, 3, 5, 7, 11, 13, 17, 19, 23, 29] --------------------------------------------

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Gurus'Network
by yawgmoth7 May 21, 2006

May 21, 2006

gurusnetwork.org is a great place to learn about programming. And a lot of the admins are Python Pro's and they are willing to help and share info. Just thought I'd mention this fairly new site.

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Re: Simple DAV server?
by Ivan Voras May 20, 2006

May 20, 2006

robert wrote: > > thanks, that's exactly to the point: > > python server.py 8080 mydavrootfolder Thanks for the patch, I assume it's free to incorporate it into the original archive? Also, see my reply to "Kyler Laird"...

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Possible constant assignment operators ":=" and "::=" for Python
by tsaar2003＠yahoo.com May 18, 2006

May 18, 2006

Hi Pythonians, To begin with I'd like to apologize that I am not very experienced Python programmer so please forgive me if the following text does not make any sense. I have been missing constants in Python language. There are some workarounds available, for example the const-module. To me, this looks quite cumbersome and very unintuitive. For the interpreter, in the efficiency-wise, I just cannot tell. For the solution I came up with two new assignment operators to the language which would create a constant name and constant value: Let's welcome the new constant assignment operators := and ::= The := assignment operator says that "declare the name to be constant and immutable". However, there might be some side-effects and the constant may not always be constant as you will see below: a = [1, 2, 3] b := [4, 5, 6] # assign [4,5,6] to 'b' and declare name 'b' to be "constant" and "immutable" c := a # assign 'a' to 'c' and declare that name 'c' is "constant" and "immutable" d = c # assign 'c' to 'd' and 'd' inherits the "immutable"-attribute from 'c', but 'd' can be assigned later e = d # assign 'd' to 'e' and 'e' inherits the "immutable"-attribute from 'd', but 'e' can be assigned later a.append( b ) print a # prints [1, 2, 3, 4, 5, 6] print c # prints [1, 2, 3, 4, 5, 6] because of the side-effect print d # prints [1, 2, 3, 4, 5, 6] as well print e # prints [1, 2, 3, 4, 5, 6] no magic here c = b # 'c' cannot be assigned as 'c' is "constant" c := b # 'c' cannot be redefined either as 'c' is "constant" c.append( 7 ) # cannot be done as 'c' is "immutable" d.append( 7 ) # cannot be done as 'd' is "immutable" as it was inherited from 'c'. e.append( 7 ) # cannot be done as 'e' is "immutable" as it was inherited from 'd'. d = [7, 8, 9] # normal variable assignment because 'd' was not declared to be a "constant" d.append( 10 ) # now allowed as 'd' is not "immutable" any more The ::= copy&assign-operator says that "make a copy of the right-hand-side object and declare the name to be constant and immutable ". This would give us a true constant object which cannot be changed. Example follows: a = [1, 2, 3] b = [4, 5, 6] c ::= a # make copy of 'a' and assign that new copy to 'c' and declare that name 'c' is a "constant" and "immutable" d = c # assign 'c' to 'd' and 'd' inherits the "immutable"-attribute from 'c', but 'd' can be assigned later e := d # assign 'd' to 'e' and declare that name 'e' is "constant" and "immutable" a.append( b ) print a # prints [1, 2, 3, 4, 5, 6] print c # prints [1, 2, 3] as 'a' and 'c' are two different objects because of the ::= print d # prints [1, 2, 3] no magic here print e # prints [1, 2, 3] no magic here either c = b # 'c' cannot be assigned as 'c' is "constant" c := b # 'c' cannot be redefined either as 'c' is "constant" c.append( 7 ) # cannot be done as 'c' is "immutable" d.append( 7 ) # cannot be done as 'd' is "immutable" as it was inherited from 'c'. e.append( 7 ) # cannot be done as 'e' is "immutable" as it was inherited from 'd'. d = [7, 8, 9] # normal variable assignment because 'd' was not declared to be a "constant" d.append( 10 ) # now allowed as 'd' is not "immutable" any more The := operator would be computionally efficient as it creates only a reference to an existing object but it may suffer from side-effects. The ::= is less efficient as it makes a copy on an existing object, but gives truly constant objects. Does this make any sense to you, or are there some fatal issues that I just happened to overlook? Br, T.S.

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CGI errror in (only in) IIS 6.0 server 2003
by nonamehkg＠hotmail.com May 18, 2006

May 18, 2006

Hi, I've been using ActivePython 2.3 (cgi) on IIS on win xp, 2000 and they work fine. Until I upgrade the system the server 2003. The ASP script engine is ok but not the CGIs. I got these errors: HTTP Error 403.1 - Forbidden: Execute access is denied. I already have execute access on the directory. Can anyone help me? ========= kychan

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Re: Default/editable string to raw_input
by Sybren Stuvel May 15, 2006

May 15, 2006

Paraic Gallagher enlightened us with: > What I am trying to do is provide a simple method for a user to > change a config file, for a test suite. My opinion: let the user edit the configuration file using his/her favourite text editor. Someone configuring a test suite should certainly be able to edit a text file. Sybren -- The problem with the world is stupidity. Not saying there should be a capital punishment for stupidity, but why don't we just take the safety labels off of everything and let the problem solve itself? Frank Zappa

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