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一元稀疏多项式编程，希望对大家的编程有点用，欢迎下载(hope it useful to you)

说明：  地球处理多边体的重磁异常的正演，主要是地球数据处理的课程的实验项目2(The forward modeling of gravity and magnetic anomalies in the earth s processing of the multilateral body is mainly the experimental project of the earth data processing course 2)

基于MATLAB，利用牛顿迭代法，求解复杂非线性方程组(Solving nonlinear equations by Newton iteration)

列句25宫的所有组合。 每行,每列,和对角线 数字和为25。(sentence of 25 out of all the combinations Palace. Each line, each and diagonal figures and 25.)

很好用的有关矩阵的各种操作，包括求逆，特征值，特征向量，svd分解等(good part of the matrix of various operations including inverse, eigenvalues, eigenvectors, svd decomposition, etc.)

说明：  自适应simpson算法，数值分析考试用的(Adaptive Simpson algorithm for numerical analysis test)

针对三维问题，建立四面体单元的有限元方法(Finite element method for establishing tetrahedron element)

这些代码可以用于产生一系列随机数，可以根据需要使用。(These codes can be used to generate a series of random numbers may be used as needed.)

ABAQUS中用户材料子程序UMAT的开发主要解决两方面的问题：本构模型的建立和积分算法的选择。 本文主要研究非线性材料的UMAT实现方法，并重点研究其迭代算法部分，目前，用户材料子程序UMAT的迭代算法主要是常刚度法，常刚度法的优点在于算法原理较简单，程序编写较方便，缺点是当遇到复杂非线性材料时，其迭代次数较多，收敛速度也较慢，在这个情况下，本文采取的是一种迭代次数较少且收敛速度较快的切线刚度法，具体就是采用FORTRAN语言编制了基于Von-Mises模型的接口程序,并采用切线刚度算法，通过与ABAQUS自带本构关系计算的结果相比较，验证其正确性。(This paper studies the user subroutine UMAT of ABAQUS development methods, the use of FORTRAN language isotropic hardening material model of the interface program, studied the effects of such material is extremely elastic-plastic constitutive relation method. This article UMAT tightly around the secondary development of technology, the first principle of its interface detail, and then for the theory of nonlinear finite element incremental stiffness of the regular tangent stiffness method and the theory of algorithms to do an in-depth analysis of deduced a regular tangent stiffness and rigidity of the law of the specific expression of algorithm theory, and then the preparation of the two algorithms, respectively, of the UMAT program, and finally the establishment of a specific model checking, bringing with ABAQUS elasto-plastic constitutive relation of the calculated results compared to verify the correctness of the two.)

最小二乘法寻找最佳函数匹配，用以数值计算，优化曲线(The least square method is used to find the best function matching for numerical calculation and curve optimization.)