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自作BASICプログラム博物館．　　18 Apr 2024　Y.Okamoto
Museum of my old BASIC programs

FaceBookで紹介した古い自作プログラムの紹介です（以下FBより）．
This is an introduction of old program that I introduced on my FaceBook (from my FB below)，

その後HDDを探したら，BASIC習作時代のプログラムがいくつも出てきたので，Linux上のエミュレータ実行画面をいくつか紹介します．主に1980年代後半のものです．640x400の今となっては極小画面で実行していました．懐かしいです．Linux上の画面では少し汚くなりますが，拡大しています．また最後にN88互換BASICという古いwindows95用のエミュレータもwineで実行できたので，そちらの画面も紹介します．

After that, I salvaged my HDDs and found some programs from my BASIC learning period, so I introduce some emulator execution screens on Linux. They are mainly from the late 1980s, when I was running on a 640x400 screen, which is very small nowadays. I also show the screen of N88BASIC compatible, an old emulator for windows 95, which could be run on "wine".

３体問題ならぬ７体問題の軌道計算．ケプラーの法則に従う惑星軌道の動きが実感できます．惑星の初速度を少しいじると，その惑星の動きで擾乱されて，その後の太陽系が不安定となり，いくつも惑星が弾き飛ばされます．我々の現在の太陽系はいわばそうした誕生時の擾乱が，落ち着いた45億年以降の，安定した時代の申し子と言えます．
Calculate orbits for the 7-body problem instead of the 3-body. You can feel the movement of the planetary orbits obeying Kepler's law. If the initial velocity of a planet is slightly changed, the planet's movement will cause a disturbance that will destabilize the solar system, and many planets will be thrown off. This program shows why our solar system keep be stable after 4.5 billion years, when the disturbances at the time of birth have settled down.

当時岩波の「科学」に，東大の岡本隆さんがアンモナイトの成長モデルを載せていました．たった３つのパラメータで，アンモナイトの殻成長の多様性を再現できるとする数理モデルでした．それを真似て作ったものです．
At the time, Prof. Takashi Okamoto of the University of Tokyo published an ammonite growth model in Iwanami's “Kagaku” magazine. It was a mathematical model that could reproduce the diversity of ammonite shell growth with only three parameters. This model was copied by me and reproduced.

これは同じみの均時差のグラフです．これは緑と赤の選を与えて，グラフ用紙上でその足し算引き算をして，黄色の均時差曲線を描く実習に使っていました．
This is a graph of "Equation of Time". This was used for practice in drawing the yellow lien plot by adding and subtracting the green(Effect of Orbit Eccentricity) and red line(Effect Obliquity) on the graph paper.

当時流行りだした「複雑系」のセル・オートマトン１次元成長モデルです．
This is a one-dimensional growth model of a cellular automaton for “complex systems” that was popular at the time.

こちらは当時，大阪市立大の情報地質の人たちが，地質図の３D化の本を出していて，その模型を作りたくて作成したものです．地形と交差する地質図境界を平面の方程式で表し，その不等号関係によって立体地形図を色分けします．これは褶曲した地層の表示です．描画に７分近くかかっています．当時，新任以来務めていた大阪府立Y高校の生徒と，地形図の数値化に取り組んでいて，立体地図は岩湧山の1/25000地形図に5mm間隔の格子を引いて，その交点の標高を等高線から眼で読みとるという，大変な作業でしたが生徒が，それをやり遂げたのには感心しました．当時の大阪府の地学クラブ発表会で生徒が発表したのを覚えています．現在の地形数値モデルDEMのいわば端緒となる研究でした．そのときの会場が附属天王寺の小講堂でまさか，その10数年後に自分の勤務先となるとは思いもしなかった日々です．
At the time, the geo-informatics laboratory at Osaka City University was publishing a paper and books on 3D geological maps, and I wanted to make a model of the book. The geologic map boundaries that intersect the topography are represented by plane equations, and the 3D topographic map is color-coded according to the inequality relations between them. This is a display of folded strata. It took nearly seven minutes to draw on the N88Basic emulating platform. The students at Osaka prefectural Y High School, where I had been working as a new commer, and I was working with some students on the digital elevation map. I remember that the students made a presentation at the Earth Science Club of Osaka Prefecture at that time. This research was the beginning of the current numerical model of topography, DEM, so to speak. I never thought that I would be working in the same school, where a small auditorium of Tennoji Highschool attached to Osaka-Kyoiku University more than 10 years after.

クレータのサイズ−個数分布を再現したもの．こちらもその後の附属高地学部のクレータ研究につながっていきます．This is a reproduction of the size-number distribution of craters. This also led to subsequent research on craters by the Earth Science Club of Tennoji HS attached to OKU.

地震の統計であるG-R則の成り立ちを説明する，Bakらの「砂山モデル」をPC上で再現しました．当時の府立Y高校には，神戸大で地震の統計を研究する院生であった，Mさんが教えに来てくれていて，彼から「複雑系」のいろはを教わりました．
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/JB095iB05p06853　がその頃の彼の学位論文です．
I reproduced the “Sand Pile Model” of Bak et al.1988 on a PC, which explains the origin of the G-R rule, the statistics of earthquakes. Mr. M, a graduate student of earthquake statistics at Kobe University, came to "Y" High School and taught me the basics of “complex systems”.

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/JB095iB05p06853　His doctoral paper.

調子よくBASICプログラムを実行していたLinux上のVLBasicですが，やはりファイルを読みに行くとエラーとなるようです．このあたりはこれからまた調べてみます．ちなみにこのプログラムは世界地図データを読んで，地球儀のようにプロットするプログラムです．この世界地図の海岸線データは数ヶ月かけて作成した次自作の数値データでした．帝国書院の世界地図に例によって格子線を引いて，海岸線の位置を，同じく格子線を引いたPC画面にマウスで読み取っていくという，いわばマウスデジタイザをBASICで自作していました．このソフトは大作となって，あらかたのBASICコーディングテクニックはこの時に身につきました．当時私に時間をくれれば「信長の野望」をBASICで作ってみせるとすごんでいました．

VLBasic on Linux was running a BASIC program just fine, but it still seems to have an error when trying to read a file. I will look into this issue again in the future. Incidentally, this program reads world map data and plots it like a globe. The coastline data for this world map is numerical data that I created myself after several months of work. As usual, a grid line was drawn on the world map of Teikoku Shoin, and the position of the coastline was read with the mouse on the screen of the PC on which the grid line was also drawn, so to speak. This software became a major work at that time for me, and I learned most of the BASIC coding techniques from these programs. At the time, I was very confident that I could make “Nobunaga's Ambition”(Japanese famous computer game! at that time) in BASIC if you gave me some time.

こちらが古い方のN88互換BASICのwineを用いたLinux上での実行画面です．今回これがLinuxで動くことも確認できたので，こちらもそのうちWeb上でN88Basic博物館を作るつもりです．--->これがその博物館pageです！

This is a screen shot of an older N88-BASIC compatible running on Linux using wine. I have confirmed that it works on Linux, so I plan to make a N88Basic museum on the Web soon.-----> this is the page of the museum!!!