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L-system

L-system trees form realistic models of natural patterns Origins[edit] 'Weeds', generated using an L-system in 3D. As a biologist, Lindenmayer worked with yeast and filamentous fungi and studied the growth patterns of various types of algae, such as the blue/green bacteria Anabaena catenula. Originally the L-systems were devised to provide a formal description of the development of such simple multicellular organisms, and to illustrate the neighbourhood relationships between plant cells. L-system structure[edit] The recursive nature of the L-system rules leads to self-similarity and thereby, fractal-like forms are easy to describe with an L-system. L-system grammars are very similar to the semi-Thue grammar (see Chomsky hierarchy). G = (V, ω, P), where The rules of the L-system grammar are applied iteratively starting from the initial state. An L-system is context-free if each production rule refers only to an individual symbol and not to its neighbours. Examples of L-systems[edit] start : A Related:  Notions

Trace theory In mathematics and computer science, trace theory aims to provide a concrete mathematical underpinning for the study of concurrent computation and process calculi. The underpinning is provided by an algebraic definition of the free partially commutative monoid or trace monoid, or equivalently, the history monoid, which provides a concrete algebraic foundation, analogous to the way that the free monoid provides the underpining for formal languages. The power of trace theory stems from the fact that the algebra of dependency graphs (such as Petri nets) is isomorphic to that of trace monoids, and thus, one can apply both algebraic formal language tools, as well as tools from graph theory. V.

Lehrstuhl Grafische Systeme - Projekte - Virtuelle Pflanzen Relationale Wachstumsgrammatiken als Basis für ein mehrskaliges metabolisches Strukturmodell der Gerste: Neue Techniken der Informatik für Functional-Structural Plant Models (FSPM) Im Rahmen des Vorläuferprojekts wurde die formale Modellspezifikations-Sprache der Relationalen Wachstumsgrammatiken (Relational Growth Grammars, RGG) entwickelt, mit der interaktiven Software GroIMP (Growth Grammar Related Interactive Modelling Platform) operabel gemacht und an ersten Beispielen demonstriert. Da Formalismus und Software zunächst schrittweise ausgebaut und getestet werden mussten, waren diese Beispiele bisher auf sehr ausschnitthafte Modelle beschränkt. Kooperationspartner: Institut für Pflanzengenetik und Kulturpflanzenforschung (IPK) Gatersleben, Dr. Abschlussbericht andere Projekte am Lehrstuhl zurück zur Homepage des Lehrstuhls

Rewriting In mathematics, computer science, and logic, rewriting covers a wide range of (potentially non-deterministic) methods of replacing subterms of a formula with other terms. What is considered are rewriting systems (also known as rewrite systems or reduction systems). In their most basic form, they consist of a set of objects, plus relations on how to transform those objects. Rewriting can be non-deterministic. One rule to rewrite a term could be applied in many different ways to that term, or more than one rule could be applicable. Rewriting systems then do not provide an algorithm for changing one term to another, but a set of possible rule applications. Intuitive examples[edit] Logic[edit] In logic, the procedure for obtaining the conjunctive normal form (CNF) of a formula can be conveniently written as a rewriting system. (double negative elimination) (De Morgan's laws) (Distributivity) where the symbol ( Linguistics[edit] Abstract rewriting systems[edit] Example 1. , and y is irreducible. .

powerPlant | Free Graphics software downloads Currying This article is about the mathematical technique. For the cooking process of this name, see Curry. For the leather finishing process, see Currier. Motivation[edit] Currying is similar to the process of calculating a function of multiple variables for some given values on paper. For example, given the function To evaluate , first replace with Since the result is a function of , this new function can be defined as Next, replace the argument with , producing On paper, using classical notation, this is usually done all in one step. If we let f be a function then the function h where is a curried version of . is the curried equivalent of the example above. Definition[edit] Given a function of type , currying it makes a function . takes an argument of type and returns a function of type . The → operator is often considered right-associative, so the curried function type is often written as . is equivalent to Mathematical view[edit] In a set-theoretic paradigm, currying is the natural correspondence between the set to

GroIMP Free Download Growth Grammar-related Interactive Modelling Platform, GroIMP for short is a 3D-modelling platform. GroIMP distinguishes itself from other modelling software by the modelling potential of growth grammars. This potential is made accessible by the integration of the modelling language XL. Here are some key features of "GroIMP": Interactive editing of scenesRich set of 3D objects, including primitives, NURBS curves and surfaces, height fieldsMaterial options like colours, texturesReal-time rendering using OpenGLExport to POV-Ray, a free ray-tracerExport to DXF, partial export to VRML/X3DThe built-in raytracer Twilight renders the sceneA light-model based on the built-in raytracer computes the distribution of light within a scene Requirements: Java Runtime Environment

Pointer (computer programming) In computer science, a pointer is a programming language object, whose value refers to (or "points to") another value stored elsewhere in the computer memory using its address.[2] A pointer references a location in memory, and obtaining the value stored at that location is known as dereferencing the pointer. As an analogy, a page number in a book's index could be considered a pointer to the corresponding page; dereferencing such a pointer would be done by flipping to the page with the given page number. A data aggregate (or just aggregate) is a group of primitives that are logically contiguous in memory and that are viewed collectively as one datum (for instance, an aggregate could be 3 logically contiguous bytes, the values of which represent the 3 coordinates of a point in space). In the context of these definitions, a byte is the smallest primitive; each memory address specifies a different byte. A one byte offset, such as the hexadecimal ASCII value of a character (e.g.

FISA - Relationale Wachstumsgrammatiken als Basis für ein mehrskaliges metabolisches Strukturmodell der Gerste: Neue Techniken der Informatik für Functional-Structural Plant Modells (FSPM) Beschreibung: Im Rahmen eines ausgelaufenen DFG-Projekts wurde die formale Modell-spezifikations-Methode der Relationalen Wachstumsgrammatiken (Relational Growth Grammars, RGG) entwickelt, mit der interaktiven Software GroIMP (Growth Grammar Related Interactive Modelling Platform) operabel gemacht und an ersten Beispielen demonstriert. Da Formalismus und Software zunächst schrittweise ausgebaut und getestet werden mussten, waren diese Beispiele bisher auf sehr ausschnitthafte Modelle beschränkt. Ausführendes Institut: Abteilung Ökoinformatik, Biometrie und Waldwachstum Details von Abteilung Ökoinformatik, Biometrie und Waldwachstum Übergeordnete Institution: Georg-August-Universität Göttingen Details von Georg-August-Universität Göttingen (Niedersachsen) Laufzeit: Förderprogramm: DFG Einzelförderung Details von DFG Einzelförderung Fachgebiet: PflanzenbauInformatik Forschungszweck: Grundlagenforschung Förderer: Deutsche Forschungsgemeinschaft (DFG) Details von (DFG) Träger: Weitere Informationen:

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