随笔分类 - 2. FoundationClasses
Foundation Classes provide a variety of general-purpose services such as:
•Primitive types, strings and various types of quantities
•Automated management of heap memory
•Exception handling
•Classes for manipulating data collections
•Math tools such as vectors, matrices and primitive geometric types
•Basic services for saving data in ASCII files
•Primitive types, strings and various types of quantities
•Automated management of heap memory
•Exception handling
•Classes for manipulating data collections
•Math tools such as vectors, matrices and primitive geometric types
•Basic services for saving data in ASCII files
摘要：OpenCASCADE中提供一种空间查找二叉树算法NCollection_UBTree，字面意思是非平衡二叉树Unbalanced Binary Tree。把上图中的数字换成包围盒，构造二叉查找树。为了解决查找二叉树单链问题，加入随机处理，可以使查找性能达到O(log(N))，相对普通遍历速度而言还是不错的。本文结合示例代码说明如何使用这个非平衡二叉树。
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摘要：flex&bison在occt中的应用。
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摘要：OpenCASCADE编码规范-内存对齐
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摘要：Boost test vs2013 fatal error C1001
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摘要：在科学技术领域里常常提出求解非线性方程组的问题，例如，用非线性函数拟合实验数据问题、非线性网络问题、几何上的曲线曲面求交问题等。OpenCASCADE中有关于非线性方程组定义的类及其求解类，本文主要介绍如何在OpenCASCADE中定义非线性方程组，及对其进行求解。
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摘要：C语言预处理命令详解
转载：https://www.cnblogs.com/clover-toeic/p/3851102.html
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摘要：Abstract. Bounding Volume Hierarchy(BVH) organizes geometric objects in the tree based on spatial relationships. Each node in the tree contains an axis-aligned bounding box of all the objects below it. Bounding volume hierarchies are used in many algorithms to support efficient operations on the sets of geometric objects, such as collision detection, ray-tracing, searching of nearest objects, and view frustum culling. The paper focus on the usage of BVH on TopoDS_Shape, and its application.
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摘要：对于几何造型内核OpenCASCADE，由于会涉及到大量的数值算法，如矩阵相关计算，微积分，Newton迭代法解方程，以及非线性优化的一些算法，如BFGS，FRPR，PSO等等用于多元函数的极值求解，所以这些数值算法的性能直接影响系统的性能。软件的性能优化是计算机软件开发过程中需要一直关注的重要因素，因此有必要学习下C++应用程序性能优化的方法。
在网上寻找相关资料时，发现这方面的资料也很少，最后发现一本由电子工业出版社出版的《C++应用程序性能优化方法》，从中可以学习下IBM的性能优化方法。
本文主要结合《C++性能优化方法》并结合代码实例来说明内存优化处理对程序性能的影响。看完本书，其实发现C++性能优化方法主要还是依赖的计算机相关的基础知识，比如说计算机操作系统，数据结构与算法等等。
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摘要：Abstract. OpenCASCADE provide data structure of any expression, relation or function used in mathematics. Flex and Bison are tools for building programs that handle structured input. They were originally tools for building compilers, but they have proven to be useful in many other areas. The Expression Interpreter in OpenCASCADE is made by Flex and Bison. So let’s know something about Flex and Bison.
Key Words. OpenCASCADE, Expression Interpreter, Flex, Bison
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摘要：Abstract. The common math algorithms library provides a C++ implementation of the most frequently used mathematical algorithms. These include: algorithms to solve a set of linear algebraic equations, algorithms to find the minimum of a function of one or more independent variables, algorithms to find roots of one, or of a set of non-linear equations, algorithm to find the eigenvalues and eigenvectors of a square matrix. The solver for function set is used widely in extrema value evaluation, poin
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摘要：Abstract. In calculus, Newton’s method is used for finding the roots of a function. In optimization, Newton’s method is applied to find the roots of the derivative. OPEN CASCADE implement Newton method to find the extrema for a multiple variables function, such as find the extrema point for a curve and a surface.
Key Words. Nonlinear Programming, Newton Method, Extrema, OPEN CASCADE
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摘要：Abstract. Multiple variable function with gradient and Hessian matrix is very very import in OPEN CASCADE optimization algorithms. In order to understand these optimization algorithm better, let’s study some basic knowledge about Gradient, Hessian Matrix.
Key Words. Multiple Variable Function, Gradient, Hessian Matrix, 最优化算法,
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摘要：Abstract. The least square can be used to solve a set of n linear equations of m unknowns(n >= m). The OPEN CASCADE class math_GaussLeastSquare implements the least square solution of the linear equations by using Gauss LU decomposition algorithm. The paper focus on the Least Square method to solve the linear equations.
Key Words. Least Square, LU Decomposition, Linear Equations
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摘要：Abstract. Power basis polynomial is the most simple polynomial function. It also be called power series. OpenCASCADE provides basic computation functions for polynomial functions, such as evaluate the result for a given polynomial, Lagrange interpolation, Hermite interpolation, .etc. The package named PLib, means Polynomial functions Library. The paper focus on the Lagrange interpolation usage of PLib.
Key Words. OpenCASCADE, PLib, Interpolation, Lagrange, 插值
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摘要：Abstract. The quaternions are members of a noncommutative division algebra first invented by William Rowan Hamilton. The idea for quaternions occurred to him while he was walking along the Royal Cannal on his way to a meeting of the Irish Academy, and Hamilton was so pleased with his discovery that he scratched the fundamental formula of quaternion algebra. There are several different ways we can express orientation and angular displacement in 3D. Here we discuss the three most important methods
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摘要：Abstract. A root-finding algorithm is a numerical method, or algorithm, for finding a value x such that f(x)=0, for a given function f. Such an x is called a root of the function f. In OpenCASCADE math package, implemente Newton-Raphson method to find the root for a function. The algorithm can be used for finding the extrema value for curve or surface, .i.e Point Inversion, find the parameter for a point on the curve or surface. The paper focus on the usage of OpenCASCADE method and its applicat
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摘要：Abstract. The conic sections and circles play a fundamental role in CAD/CAM applications. Undoubtedly one of the greatest advantages of NURBS is their capability of precisely representing conic sections and circles, as well as free-form curves and surfaces. We assume a knowledge of conics and circles, the purpose of this paper is to study them in the framework of their representation as NURBS curves.
Key Words. OpenCASCADE, Conic Curves, Circle, Convert, BSpline Curve
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摘要：Abstract. Rational Bezier Curve can represent conic curves such as circle, ellipse, hyperbola, .etc. But how to convert a conic curve to BSpline curve is still question, i.e. Represent a conic curve in BSpline form. The key point of Hyperbola conversion is to calculate the 2nd pole and its weight factor. The paper focus on the hyperbola convert to the BSpline curves.
Key Words. OpenCASCADE, Convert, Hyperbola, BSplineCurve, Conic Curve
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