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For 2021 - online Python 3 training - see ((here)).

Our plans were to retire in summer 2020 and see the world, but Coronavirus has lead us into a lot of lockdown programming in Python 3 and PHP 7.
We can now offer tailored online training - small groups, real tutors - works really well for groups of 4 to 14 delegates. Anywhere in the world; course language English.

Please ask about private 'maintenance' training for Python 2, Tcl, Perl, PHP, Lua, etc.
Where do I start when writing a program?

Q: Where do I start when writing a program?

A: Start off by thinking about what you want to achieve, and what inputs you have available to you. In other words, look at what the customer provided and what the customer wants to get (yes, you may be your own customer!). If it's too much to think through in one step, split it into a series of stories, and write each stage in turn, frequently refactoring as you go.

As well as the inputs and outputs, think about the major structures you'll use internally within your program - your collection variables (arrays, lists, hashes, dictionaries, tuples ... whatever is available in the language of your choice), and think what is likely to be common code which will allow you to (re)use you own code later, or to call in someone else's stuff from day 1.

When you've given this some thought and you're moving to a coding stage, write your comments first - they will in essence form a textual flowchart, help you identify pitfalls early, and avoid you coding up too many blind alleys.

On today's Perl Course, I went through these principles, in order to start answering the question "what operating system(s) do people who use my website run?" .... you can see my initial (all comments!) design here. I then went on to add some code - a first test or - 'spike' solution - see here. The results of running that program on a recent log file from our own site:

Dorothy-2:perl grahamellis$ perl whatos
There are 80520 good records and 34 mucked up ones
unknown ... 49716
Googlebot ... 9574
Windows NT 5\.1 ... 21230
Dorothy-2:perl grahamellis$


which is very short .. but an excellent demonstration of principle.

Although I am talking about Perl in this note, you'll find that what I've suggested is equally suitable for use in Python, PHP, Ruby, Lua ... indeed, in all the other languages we teach. If what I've written is of interest to you, have a look at our "learning to program in ...." courses, where an extra day on the front of the main course helps newcomers to programming. But if it's stuff you're happy with, start on our ".... programming" courses which assume prior knowledge of things like this
(written 2009-06-11, updated 2009-06-12)

 
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
Q101 - Object Orientation and General technical topics - Programming Principles
  [2001] I have not programmed before, and need to learn - (2009-01-19)
  [2022] Pre and post increment - the ++ operator - (2009-02-03)
  [2310] Learning to write high quality code in Lua - (2009-07-30)
  [2327] Planning! - (2009-08-08)
  [2415] Variable names like i and j - why? - (2009-09-22)
  [2510] The music of the stock market - (2009-11-22)
  [2550] Do not copy and paste code - there are much better ways - (2009-12-26)
  [2586] And and Or illustrated by locks - (2010-01-17)
  [2737] Improving your function calls (APIs) - General and PHP - (2010-04-24)
  [2769] Easy - but for whom? - (2010-05-18)
  [2878] Program for reliability and efficiency - do not duplicate, but rather share and re-use - (2010-07-19)
  [2915] Looking up a value by key - associative arrays / Hashes / Dictionaries - (2010-08-11)
  [2964] An introduction to file handling in programs - buffering, standard in and out, and file handles - (2010-09-21)
  [3026] Coding efficiency - do not repeat yourself! - (2010-11-02)
  [3456] Stepping stones - early coding, and writing re-usable code quickly - (2011-09-24)
  [3542] What order are operations performed in, in a Perl expression? - (2011-12-07)
  [3548] Dark mornings, dog update, and Python and Lua courses before Christmas - (2011-12-10)
  [3551] Some terms used in programming (Biased towards Python) - (2011-12-12)
  [3673] Object oriented or structured - a comparison in Python. Also writing clean regular expressions - (2012-03-26)
  [3878] From Structured to Object Oriented Programming. - (2012-10-02)
  [3928] Storing your intermediate data - what format should you you choose? - (2012-11-20)
  [3954] Lesson 1 in programing - write clean, reuseable and maintainable tidy code - (2012-12-16)
  [4003] Web and console - same principle, same code - Ruby example - (2013-02-14)
  [4061] Seamless, integrated IT - we have a long way to go! - (2013-04-11)
  [4090] Test Driven Development in Python - Customer Comes First - (2013-05-16)
  [4118] We not only teach PHP and Python - we teach good PHP and Python Practice! - (2013-06-18)
  [4153] Rooms available tonight - how to code an algorithm from first principles - (2013-08-19)
  [4206] Writing the perfect program in Tcl? - (2013-11-13)
  [4325] Learning to program - what are algorithms and design patterns? - (2014-11-22)
  [4611] Hungarian, Camel, Snake and Kebab - variable naming conventions - (2016-01-03)
  [4632] Remember to ask the question before you listen for the answer - (2016-01-26)
  [4645] What are callbacks? Why use them? An example in Python - (2016-02-11)

P050 - Perl - General
  [116] The next generation of programmer - (2004-11-13)
  [400] New in the shops - (2005-08-01)
  [743] How to debug a Perl program - (2006-06-04)
  [1750] Glorious (?) 12th August - what a Pe(a)rl! - (2008-08-12)
  [1897] Keeping on an even keel - (2008-11-21)
  [2242] So what is this thing called Perl that I keep harping on about? - (2009-06-15)
  [2374] Lead characters on Perl variable names - (2009-08-24)
  [2504] Learning to program in ... - (2009-11-15)
  [2736] Perl Course FAQ - (2010-04-23)
  [2783] The Perl Survey - (2010-05-27)
  [2825] Perl course - is it tailored to Linux, or Microsoft Windows? - (2010-06-25)
  [2971] Should the public sector compete with businesses? and other deep questions - (2010-09-26)
  [3093] How many toilet rolls - hotel inventory and useage - (2010-12-18)
  [3322] How much has Perl (and other languages) changed? - (2011-06-10)
  [3332] DNA to Amino Acid - a sample Perl script - (2011-06-24)
  [3407] Perl - a quick reminder and revision. Test yourself! - (2011-08-26)
  [3823] Know Python or PHP? Want to learn Perl too? - (2012-07-31)
  [3902] Shell - Grep - Sed - Awk - Perl - Python - which to use when? - (2012-10-22)
  [3911] How well do you know Perl and / or Python? - (2012-11-04)
  [4296] Polishing the Perl courses - updated training - (2014-09-17)
  [4301] Perl - still a very effective language indeed for extracting and reporting - (2014-09-20)

G999 - Well House Consultants - Keynote
  [164] Well House Consultants - review of 2004 - (2004-12-31)
  [225] 10 years and counting - (2005-02-23)
  [295] Pricing strategy - simple and fair - (2005-04-29)
  [360] Spring turns to Summer - (2005-06-26)
  [419] Most popular courses - (2005-08-19)
  [428] Swindon - Chippenham - Melksham - Trowbridge - Westbury train service - (2005-08-29)
  [452] Is enough enough? - (2005-09-27)
  [464] Technical Loneliness - (2005-10-14)
  [549] 2005 - Come as a student, leave as a friend - (2005-12-31)
  [626] Not just a pretty face to answer the phone. - (2006-02-26)
  [695] In the hospitality business - (2006-04-23)
  [774] Bed and Breakfast, or Hotel? - (2006-06-22)
  [845] Course scheduling and Geekmas - are they traditions yet? - (2006-08-26)
  [890] Open - (2006-10-09)
  [898] Courses at Well House Manor - (2006-10-19)
  [929] Presenting Melksham - for a weekend away in Wiltshire - (2006-11-17)
  [1079] Wilts and Berks - two conference / training rooms in Melksham - (2007-02-14)
  [1161] A contrast in room rates and facilities - (2007-04-25)
  [1245] Ensuring that our tutor answers YOUR questions - (2007-06-25)
  [1317] 2008 course schedule - Perl, Python, PHP, Linux, Java Deployment, Ruby and more - (2007-08-23)
  [1319] Customer feedback - lifeblood of a business - (2007-08-25)
  [1414] What we teach - expained for the non-technical - (2007-10-28)
  [1481] The Christmas Letter - (2007-12-22)
  [1492] Well House Consultants Training and Hotel - 2008 news - (2008-01-01)
  [1555] Advanced Python, Perl, PHP and Tcl training courses / classes - (2008-02-25)
  [1615] PHP training courses every month - (2008-04-18)
  [1676] A warm welcome for visitors from the USA - (2008-06-14)
  [1748] Hotel room prices - Melksham, Wiltshire - (2008-08-11)
  [1773] The Longest Possible Day - (2008-08-26)
  [1857] November and December Public Course Schedule - (2008-10-27)
  [1859] Wiltshire at dawn - the tourist trail - (2008-10-29)
  [1929] 2009 - Hotel, Meeting, Training Course prices - (2008-12-07)
  [1955] How to avoid duplicating web page maintainance - (2008-12-20)
  [1975] Well House Manor Hotel - on plan for 2009 business guests - (2009-01-03)
  [2144] Looking for a career change - Physician to Web Site Designer - (2009-04-28)
  [2216] Past Delegate Offer - Summer Holiday / Weekend Break - (2009-06-03)
  [2326] Learn a new programming language this summer. - (2009-08-06)
  [2384] Looking ahead to the Autumn season of training and accommodation - (2009-08-28)
  [2483] Clustering on Tomcat - (2009-10-30)
  [2537] Faster network, but not faster browsing until ... - (2009-12-14)
  [3164] Brown - or Mrs Sally Brown, accountant from Whitstable? - (2011-02-10)
  [4588] What teach you in a week stays with you for a decade - (2015-11-29)


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Do not re-invent the wheel - use a Perl module
Some other Articles
Why sendmail one way, and pop3 the other?
What is CGI.pm / A dozen new examples
Running a piece of code is like drinking a pint of beer
Do not re-invent the wheel - use a Perl module
Where do I start when writing a program?
Learning PHP, Ruby, Lua and Python - upcoming courses
Revision / Summary of lists - Perl
How important is a front page ranking on a search engine?
Trowbridge - a missed opportunity? Melksham - into the breach?
CSS Style Diagrams - working out where attributes come from
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This is a page archived from The Horse's Mouth at http://www.wellho.net/horse/ - the diary and writings of Graham Ellis. Every attempt was made to provide current information at the time the page was written, but things do move forward in our business - new software releases, price changes, new techniques. Please check back via our main site for current courses, prices, versions, etc - any mention of a price in "The Horse's Mouth" cannot be taken as an offer to supply at that price.

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