Shlomi Fish as a Programmer - the pre-Elpas Years
Table of Contents
- Table of Contents
- Document Information
- XT's, BASICs and DOS
- Learning C
-
Some BASIC Programs that Saved the Day
- Positive (albeit Small) Income
- A Brief Encounter with Pascal and the Israeli Education System
- Epilogue
Document Information
XT's, BASICs and DOS
The first time I programmed was for an XT computer my father bought, and for the BASIC that came hard-coded in the ROM and loaded in case you did not insert a floppy disk in the drive. I was in my 4th grade and my two best friend got jealous of the computer and their parents promptly bought ones for them too. Together, we bought a set of booklets about teaching BASIC in DOS called "Mahsheveth" (or "מחשבת" in Hebrew) and helped each other learn the language.
One of the property of the BIOS was that you could not save your programs. If the computer was rebooted (in order to load a floppy disk to play an old DOS game like Digger), you had to type it all over again. Luckily, Mahseheveth introduced DOS and using files and the native DOS basic interpreter in the fourth chapter and we could save our files on floppy disks instead.
Another good property of the Mahsheveth series was that its writers were fully aware of Structured Programming, and knew that BASIC did not enforce it on the programmer. They taught us about GOTO's and IF's right away, but instructed them to use them to construct conditionals and loops instead of a GOTO spaghetti. (Of which I've seen once in an old code when I was a already a Technion student). Thus, the later transition to C/C++ was quite natural.
The first programs I wrote were nearly identical to the ones that appeared in the answers section. The latter ones deviated very much, which made me a bit distressed that we made things differently. Back then, I did not hear of the "There's more than one way to do it" idiom. Eventually, I realised that everyone did things a little differently and that I should be content with it.
My father upgraded to later DOS versions, and DOS 5.0 came with a nice BASIC front-end called QBASIC, which had a nice editor with menus and many editing commands, an online help, and produced fast code. I liked it a lot. At one time I tried to write a computer game with it in BASIC, and then was told that it no longer needed line numbers unless for explicit labels. It was a bit like Visual Basic in this regard.
Learning C
My friend became a better DOS engineer than I was, and soon bought Microsoft Quick C, learned about programming hardware and over-riding the BIOS, x86 Assembler and other things. Back then, the only languages we knew about were BASIC (which we knew was nice and easy but pretty lame), Pascal (compiled, and much better than basic), C (something that was supposed to be even more advanced than Pascal), and we may have heard of Prolog, LISP, Fortran. Awk? Perl? Tcl? SmallTalk? Matlab? We've never heard of them at all.
So I instructed my father to buy me a C compiler package in one of his trips abroad and he bought me Borland's Turbo C++. I learned C and C++ through its manual. One of the thing I did not understand was pointers, until I went to a hike where an army programmer explained to me that they were simply addresses in memory which I can put or take values from, and a bit about pointer arithmetics. This gave me a large momentum. I also learned about classes and objects and templates which although a simple concept fascinated me.
I took my liberty to write a module of components which I dubbed CSEE.c, for doing various graphical things. My friend was at first surprised at that (it was not a standalone program), but later on told me people distributed and sold such libraries and software development kits all the time. It included some very nifty user-land routines, but I doubt it will run on anything besides an old Borland DOS Compiler.
I then started writing CCALC.c which was a library of miscellaneous numerical routines that were not built in in C. It included rational fractions, factoring numbers, checking for primality (in several ways), and other stuff. The code should work on any 16-bit compiler but will take some tweaking to get it to be 32-bit and 64-bit ready. Note that everything it does can be done with GNU's GMP, or OpenSSL, or other open-source components available on the Net. I can distribute it as open-source but see little point in doing so, because it's pretty much useless in today's standard, and a mathematically-inclined programmer can write such routines on his own.
Some BASIC Programs that Saved the Day
When my father bought a CD-ROM drive for our computer (a double-speed one - !), he brought a pack of 10 example CDs that were legitimate but were bought for a very small price. One of them contained various demos, by the Future Crew, the Electro Motive Force and others. I was very impressed by "Unreal". I remember the Fluttering Flag effect they had and had an idea on how to reproduce it.
A quick QBASIC program produced a very similar effect. I translated it to C and got faster animations, but even the QBASIC one was also quite fast.
I studied Physics in a laboratory building called ``Hemda'', and we had DOS machines for students to use. Once when I had a spare time, I reproduced the fluttering flag demo. The librarian (with whom I became a very good friend) was very impressed, and requested that I kept the program there.
Another issue was when my friend wondered what was the average of a 4d6 minus the least score method of generating AD&D abilities was. He used a C (or BASIC perhaps) program with several loops to calculate. I actually tried to find a mathematical solution and was eventually able to. (refer to my "Combinatorics and the Art of Dungeons and Dragons" article ). But I did check my final result (which I could calculate with a hand calculator) with a program I wrote to see they were identical.
I asked the people at ``Hemda'' this question, and many of them, including my Physics teacher pondered them for a long time. I eventually showed them my way and took my teacher to the library to write a QBASIC program that calculated it both ways. Another teacher that passed by turned out to have reached a similar conclusion by himself. My teacher said I should keep the basic program there as well, as he may find a use for it.
Note that using brute force (i.e: 4 loops) will work quickly enough in this case. However, as the number of dice grows the order of growth grows exponentially and so it is not an efficient algorithm. The method I (and later on other people I told them this riddle) found has a polynomial complexity, which is much nicer than exponential.
The Most Under-estimated Feature of Excel
When my father bought Excel 4.0 for Windows 3.1 I realized it came with a nice scripting language called Visual Basic for Applications. It enabled me to write a factorial function, access the contents of cell, and script every aspect of the application. I liked it very much.
One time my father needed to process an ASCII file and insert it into a spreadsheet. He is a bio-technologist and that was the output of one of his devices. I wrote a first version in the scripting language of Quattro-Pro for DOS (which I did not like), but eventually my father told me that they use Excel 95 for Windows 95 at work, so I can use VBA. In Visual Basic for Applications it was much easier, and also ran faster than the Quattro Pro program, and was easier to maintain. My father sent them my code and telling them it was quite slow but faster than inputting the data by hand (and less prone to errors).
Retrospectively, I think an equivalent Perl Program (or even an Awk one) would have done it in a fraction of the time of the VBA one. But I don't think my father could have allowed himself to install Perl on each of the computers at his foreign workplace, so VBA had to do. (I remember using some DJGPP tools for something similar later on, and my father installed the awk.exe program. That was after I learned UNIX)
Positive (albeit Small) Income
My first gig was to translate a document from English to Hebrew. I remember my friend and I (still the same friend) sitting in front of the computer and translating the introduction together. It was great fun, and our employer enjoyed it.
Then my friend decided he was too busy for it and we should split the work and each translate separately (a big Extreme Programming No-no). It took me a long time to do my translation and my father corrected my mistakes. Still, it was not of a very good quality and I did not spend a lot of time focusing on a perfectly correct translation. There were also many technical terms.
I got my money eventually but my employer said he was willing to pay only because I was underage (that was my 9th grade). My friend claimed to have spent 4 times as much as I did and produced better results. Both my friend and I got 100 NIS which at that point was $50. With all the time I spent, I think it barely covered the computer's electricity consumption. As a developer, I later on was able to earn much more for my time.
Another gig I got was when my friend had to do a programming project for his school of querying the school's global schedule. He needed something that would be able to translate the Civil Calendar into the Jewish Calendar (as many of the vacations in Israel happen on Jewish dates). I read about it in the Hebrew Encyclopedia, and eventually was able to come up with a method to do the conversion. I went to my friend house, and explained to him how to do it. He said: "Shlomi, if you can do it, why don't you write it for us, and we'll credit you for it". Having a lot of time I agreed.
Using Turbo C++, I started writing a crude, 16-bit code to convert Gregorian dates to Jewish dates. The Jewish calendar is not simple at all, as it has quite a lot of religious caveats. Nevertheless, the code was eventually working. I use some C++ features, but my friend later insisted on his program being pure ANSI C and said I should convert them all to C. A beautiful class I wrote and some operator overloading of it had to be sacrificed for this sake.
My friend integrated the code with his project, and later he phoned me to tell that he and his partner agreed to give me 0.5% of their future earnings. There weren't any, but I still enjoyed the experience.
I later found on the Internet a beautiful 32-bit C code that supported conversion between these two calendars and two others. Re-inventing the wheel is instructive but you don't always come up with a better wheel. At least I now have some knowledge of how the Jewish Calendar is calculated, but still don't keep track of the Hebrew date. :-)
At one summer I worked on the assembly line of my father's bio-technology firm. I assembled various pieces of kits they shipped and sold. Others assembled the entire kit. It took a long time and a lot of money to develop and continue develop the kits. But you actually needed humans and machines doing physical work to mass produce them.
I believe it gave me some perspective later as a programmer. A bit sequence (a computer program, an mp3, a digitized book or whatever), takes a long time to develop (if it is indeed worthy of something - catting /dev/urandom will not yield something sensible) but can be duplicated and distributed at almost zero cost. By working in an assembly line I understood there was not a good enough reason for me to charge people money for getting what I did, even if it took me a lot of time to develop, debug and finalize. Too bad Microsoft, the RIAA et al. do not understand this (or make it seem like they don't).
I'm not saying selling commercial digital content is immoral or illegal. I'm just saying that you cannot expect people to pay for it 100% of the time. They can copy it and they will. Your model has to be different if you wish to earn money. But this is out of the scope of this document.
A Brief Encounter with Pascal and the Israeli Education System
When I joined the 10th grade, my first grade of high school, we had our first Computer Science lesson. Several students (including me) explained to the teacher (a young woman) that we already knew programming well, even in Pascal. I knew C which I learned over the summer. She became a bit distressed from our mass reaction that we wanted something more challenging to learn. Eventually, we reached a compromise that I cannot quite recall.
At class, we learned about computers in general, about various programming languages (not Perl or LISP or something similar, as far as I recall, but COBOL, Prolog, C, and other relatively low-level languages), about how to write good pseudo-code, a run-time table of the program, and then to run it in a computer. I think it was not a complete waste of time, as I still encountered pseudo-code later, learned about Euclid's gcd algorithm, etc.
Once when we were given an assignment to check a number for primality I used goto in a Pascal program because I did not know the syntax for writing functions yet. I also remember using a sieve, while my teacher insisted that for every number I'll check all the number up to its square root, individually. (without remembering previous numbers). I did as I was told, even though, I knew it was a much less effective algorithm.
She was surprised when I told her about Fermat's method for checking primality ((i^p-i) mod p = 0), but naturally I eventually discovered it can have false positives albeit extremely rarely. (refer to Abelson and Sussman's "Structure and Interpretation of Computer Programs" for more information).
When we had to choose our major 5 units of our matriculation subjects, I chose Arabic instead of Computer Science, because I discovered Computer Science was not important for studying math or CS at university. It was a specialisation in Physics that was critical for the Technion (which I eventually started learning Electrical Engineering in). So, I decided that since CS would not teach me much new, I'll take Arabic, which may prove useful for better understanding of the Arabic Language and Arab culture.
I don't regret this choice. Although I mostly remember obscure grammatical rules, and while my vocabulary is slowly dwindling, I think that with some help from reference books, I can eventually be able to read Arabic texts. And I did learn a bit about the Arabic culture through such lessons.
Epilogue
After I graduated from high school, I became bored, so my father arranged for a job interview in Elpas, a company ran by one of his close friends, who finished his army service as an engineer to start a startup Electro-optics company. I eventually got the job, and so started earning a living as a programmer, while still largely dependant on my parents.
I was eventually found unsuitable for Army service, which I actually wanted to serve in, but was a bit afraid of.
The days of BASIC, C and Pascal hobbyist programmers in DOS are largely over now, highly superseded by Visual Basic/Delphi/Visual C++ programmers working for Win32, and gcc/Perl/Python/Ruby/Tcl programmers working on GNU systems (such as Linux). Even when I learned C I did not distinguish between the ANSI C functions, and those that were DOS or Borland extensions. And 16-bit programming was a bit painful and I had to use long for numbers that could get quite large.
Software Engineering is not a label - it's a process. I have constantly become and am still becoming a better software engineer. Many people are "ad-hoc programmers". They know just enough programming to survive. However, some of them are hackers. They are curious and delighted about programming and wish to learn more and more. I believe that as a child and a teenager I started as a hacker. Not a very good one, but still a computer enthusiast.
My suggestion to wannabe hackers today is to start working on a Linux system. A Mandriva Linux system with KDE and everything installed and configured, is equally as usable as Windows, but offers much more development capabilities at the fraction of the cost. It' s also based on UNIX, which is an entire software engineering culture of its own, which you can explore should you like to. But when I was 10 years old, XT's could only run DOS, and so that's what we had to do. I still believe my DOS days gave me an edge on some UNIX programmers, because I am very comfortable at the command line and at editing text while seeing how it will eventually look like in my mind's eye. I don't want "What you see is what you get". I want "What you want is what you get ASAP".
Today with KDE, GNOME and other graphical environments, even many children who are introduced to Linux, will find the command line intimidating. I don't say using a GUI does not has its advantages. But you must get to like the command line and to see things in your mind's eye. Programming, designing styled text and creating graphics happens mostly in the mind, not in your IDE , WYSIWYG word processor or Graphics program. One should realize that even if you can't see it, the computer will still be able to create it for you.
Programming and computing without using the mind's eye eventually numbs out imagination and creativity . One is used to point-and-click and getting immediate results instead of thinking about them carefully and then implementing them. But the damage is not irreversible.
Some software systems are so complex that working on them in an IDE instead of in text editors inside several console windows will give you little advantage. That will be the case for a very long time, because writing a program that can generate every algorithm for you, is not something I see as possible. You may choose to use a GUI for giving you some widgets and various bells and whistles for free. But remember that in order to be a great programmer and not just a good one, you have to think, imagine and analyse your code. There's no escaping that and I think it applies to all other fields of science and engineering as well.
