Printable progress record. Logo is a simple programming language devised by Seymour Papert for educational purposes. Students can control the movement of a turtle which draws lines on the screen.It introduces learning through robotics construction and Logo programming in an inner-city Boston public school, The Hennigan School.LOGO programming language developed by Seymour Papert and team at MIT. Seymour Papert, for the LEGO company circa 1987. Here is a promotional video produced by the Father of Educational Computing and the Maker Movement, Dr. LEGO Papert Fellowships at the MIT Media Lab Best Seymour Papert Introduces LEGO TC Logo.Its intellectual roots are in artificial intelligence , mathematical logic and developmental psychology. 4.4 Defining procedures, the need for an editorLogo was created in 1967 at Bolt, Beranek and Newman (BBN), a Cambridge, Massachusetts research firm, by Wally Feurzeig and Seymour Papert. More than 35 years later, it was formally.Modeled on LISP, the design goals of Logo included accessible power and informative error messages. The goal was to create a math land where kids could play with words and sentences. The first implementation of Logo, called Ghost, was written in LISP on an SDS 950.
![]() Logo Program Seymour Papert Free And CrossCommercial Logos that are still widely used in schools include MicroWorlds Logo and Imagine Logo. MSWLogo, and its successor FMSLogo , for Windows, are commonly used in schools in the United Kingdom and Australia. UCBLogo has only a rudimentary graphical user interface, so several projects exist that provide a better interface. It is free and cross-platform. The situation is confused by the regular appearance of turtle graphics programs that mistakenly call themselves Logo.The most broadly used and prevalent early implementation of Logo was Apple Logo, which was developed by LCSI for the Apple II computer and popular during the 1980s.The closest thing to a de facto Logo standard today is UCBLogo , also known as Berkeley Logo. There are substantial differences between the many dialects of Logo. It was interfaced with Lego bricks , although Lego decided later to use another language in the commercial Lego Mindstorms products. Although most often used for graphics, Logo can also control robots. Most Logo implementations are interpreted, but some compilers have been built, including the Lhogho compiler, by the same author as Elica. They allow for the exploration of emergent phenomena and come with many experiments in social studies, biology, physics, and other areas.Most Logos are 2D, but the Elica interpreter is notable for supporting 3D graphics. There are two popular implementations: MIT 's StarLogo and CCL 's NetLogo. Programming See also: Turtle graphicsLogo's best-known feature is the turtle, which is an on-screen cursor (derived originally from a robot of the same name), which can be given movement and drawing instructions, and is used to programmatically produce line graphics. It is also the main influence on the Etoys educational programming environment and language, which is essentially a Logo written in Squeak (a variant of Smalltalk ). ObjectLOGO is a variant with object-oriented extensions.Logo was a primary influence on the Smalltalk programming language. An interface also exists for Cricket robots. The turtle moves with commands that are relative to its own position, LEFT 90 meant rotate left by 90 degrees. Turtle geometry works somewhat differently from (x,y) addressed Cartesian geometry , rather operating in a Euclidean space (i.e., relative measures and angles without an origin, unlike coordinate-addressed systems such as PostScript ). Turtle graphics were added to the Logo language by Seymour Papert in the late 1960s to support Papert's version of the turtle robot , a simple robot controlled from the user's workstation that is designed to carry out the drawing functions assigned to it using a small retractable pen set into or attached to the robot's body.As a practical matter, the use of turtle geometry instead of a more traditional model mimics the actual movement logic of the turtle robot. Download mocrosoft office for home macCommands may be written on one line, or more. For instance, the idea of turtle graphics is also useful in Lindenmayer system for generating fractals. Turtle geometry is also sometimes used in environments other than Logo as an alternative to a strictly coordinate-addressed graphics system. Some Logo implementations, particularly those that allow the use of concurrency and multiple turtles, support collision detection and allow the user to redefine the appearance of the turtle cursor, essentially allowing the Logo turtles to function as sprites. Papert called this body-syntonic reasoning. To mainThe analogy of a turtle with a pen attached to its tail is often used. For example, one could have a helloworld.lgo which prints Hello World and becomes blank when EDALL is called: print Alternatively, one could put the command in a procedure that is run when the program is loaded. If the file being opened has commands that are not in a defined procedure they will be run on startup and will be removed from the workspace (except for variable assignments), so if the file is then saved it becomes blank. FORWARD 100 draws a square with sides 100 units longFD 100 RT 120 FD 100 RT 120 draws a triangleThe Hello World program in Logo looks like this: print Loading a file will include all its defined procedures into the currently open file. Anything written after the (semicolon) is ignored, allowing the coder to insert comments. This makes the input less onerous. REPEAT 36] Defining procedures, the need for an editorProcedures can be defined on the command line, using the TO END pair: TO CHAIR REPEAT 4 FD 200 ENDHowever, in some early Logos the procedure is limited to the physical line length of the input device.All Logos can invoke an Editor, usually by EDALL. Loops may be embedded, giving spectacular results with little effort. An approximation of a circle can be constructed easily with 360 small rotations and a step forward: REPEAT 360. REPEAT 4 The command FD 100 LEFT 90 is executed four times. FD 20 drawing a line and movingPENUP lifting the pen so it won't draw anythingPENDOWN lowering the pen so it draws againPENUP lifting the pen so it won't draw anythingPENDOWN lowering the pen so it draws againThere are three loop (repeat) commands REPEAT is one. The word CHAIR can be used as a command for example, REPEAT 4 would repeat the CHAIR operation four times.Logo was designed in spirit of low threshold and no ceiling, which enables easy entry by novices and yet meet the needs of high-powered users. Internally procedures are words and in this case, any time CHAIR is entered, the sequence REPEAT 4 FD 200 will be executed. EDALLThe new word is saved into the available vocabulary, but the definition will be lost once the Logo session is over. The pen can be restored with the command PENPAINT ( PPT ). Now any future FD movements will erase anything beneath them. Using the turtle analogy, the turtle's pen must paint, and the turtle's pen must erase.In UCBLogo, the turtle can be set to erase using the command PENERASE ( PE ). The process is the same, except that in the former a line is deposited on the display device and in the latter a line is removed.
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