What is Numerical: Definition and 772 Discussions

Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). Numerical analysis naturally finds application in all fields of engineering and the physical sciences, but in the 21st century also the life sciences, social sciences, medicine, business and even the arts have adopted elements of scientific computations. The growth in computing power has revolutionized the use of realistic mathematical models in science and engineering, and subtle numerical analysis is required to implement these detailed models of the world. For example, ordinary differential equations appear in celestial mechanics (predicting the motions of planets, stars and galaxies); numerical linear algebra is important for data analysis; stochastic differential equations and Markov chains are essential in simulating living cells for medicine and biology.
Before the advent of modern computers, numerical methods often depended on hand interpolation formulas applied to data from large printed tables. Since the mid 20th century, computers calculate the required functions instead, but many of the same formulas nevertheless continue to be used as part of the software algorithms.The numerical point of view goes back to the earliest mathematical writings. A tablet from the Yale Babylonian Collection (YBC 7289), gives a sexagesimal numerical approximation of the square root of 2, the length of the diagonal in a unit square.
Numerical analysis continues this long tradition: rather than exact symbolic answers, which can only be applied to real-world measurements by translation into digits, it gives approximate solutions within specified error bounds.

View More On Wikipedia.org
  1. Alexanddros81

    Simple Pendulum motion - Numerical Integration

    Homework Statement The differential equation of motion for the simple pendulum can be shown to be ##\ddot {θ} = -(g/L)sinθ##. Given that L=9.81 m and that the pendulum is released from rest at θ=60deg, determine the time required for the pendulum to reach the position θ=0deg. Use Δt=0.10s, and...
  2. F

    I Derivative and Numerical approach

    Hello, I am dealing with a function f(x) involving various complicated trig functions. I took the first derivative of the function f(x), which is doable, and set it to zero to find the at which value x the function f(x) would be maximum. However, once I have the derivative of f(x), it does not...
  3. F

    A Numerical solution of Hamiltonian systems

    The question is very general and could belong to another topic, but here it is. Suppose one wants to solve the set of differential equations $$ \frac{\partial x}{\partial t}=\frac{\partial H(x,p)}{\partial p},$$ $$\frac{\partial p}{\partial t}=-\frac{\partial H(x,p)}{\partial x},$$ with some...
  4. S

    Error of integration in numerical methods

    Homework Statement So this is a problem for my numerical methods class. We are doing integration and derivation. The part that I am stuck on is why does the midpoint method and trapezoidal method both have error of order ##h^2##, when the first one is one point integration method while the...
  5. Pushoam

    Length contraction -- numerical problem

    Homework Statement Homework EquationsThe Attempt at a Solution a) t' = l0/c b) ct1 = l0 /ϒ - vt1 t1 = l0 /ϒ(c + v) c) t2 = l0 / (ϒ v) Is this correct?
  6. Pushoam

    Length contraction numerical problem

    Homework Statement Homework Equations 1) k.e. = (1/2)mv2, non- relatvistic 2)K.E. = m0 c2 (ϒ -1), relativistic 3) L=L0/ϒ , Length contraction The Attempt at a Solution (A) Taking 1019 eV to be the kinetic energy of the proton, Non- relativistic calculation (1/2)mv2 = 1019 eV = 1.6 v =...
  7. M

    Numerical Nonlinear Lifting Line Theory in MA

    1. Homework Statement Hello all. It is not a homework actually. I just didn't know at which forum I should post. I am working on a MATLAB code solving the finite wing properties iteratively by using the Anderson's Numerical Lifting Line Method. However, I got some wrong results. The...
  8. awholenumber

    I Some questions from a numerical analysis book

    https://www.amazon.com/dp/1305253663/?tag=pfamazon01-20 Are all these called root finding algorithms? All of it ? <Moderator note: Link changed because of undetermined copyright situation. fresh_42>
  9. C

    MHB Numerical Analysis problem Newton's method

    Can anyone help in the solution of this problem? how can i determine the zero x*??
  10. Jamison Lahman

    Aperature, Numerical Aperature and Speed of Lenses

    I think I understand the relationship between the three, but I would like some feedback. I still am fairly unsure about lens speed and is what I'm mostly interested in. From my understanding: Aperture is the total diameter of the lens and numerical aperture is the ratio between the aperture and...
  11. S

    Numerical integration in Python (throwing a ball)

    Homework Statement I have a problem with my physics task, but you do not need to understand physics to be able to help me, because my main problem is bad programming skill. I am dealing with a problem of throwing a ball in the air at an angle between 0 an 45 degrees. I need to consider not only...
  12. E

    B Numerically Solving GRT Problems - Textbook/Article Recommendation

    Can anyone recommend a good textbook or article for numerically solving general relativity problems? Say for a planet orbiting a pair of binary stars, or even for the sun and Jupiter in our solar system?
  13. hilbert2

    Comparison of high-level computer programming languages

    A little question about the appropriateness of a certain research subject... Would it be useful to make a study of the computational effectiveness of equivalent codes written with Matlab, Mathematica, R Code, Julia, Python, etc. in a set of typical computational engineering problems like...
  14. Ian Baughman

    Courses Numerical Linear Algebra or Modern Algebra

    So I am working out a course schedule for my last two years of undergrad and have room for only one more math class but do not know which would be more beneficial. The two courses are Intro to Modern Algebra or Numerical Linear Algebra. I am working towards a bachelors degree in physics and plan...
  15. M

    Is Maple the Underrated CAS for Numerical Computing?

    Until now, I have always think of Matlab as CAS but now I know that it is not. So how do you understand this? Thank you.
  16. Conclaude

    Numerical Plot of Particle Orbits in Kerr Equatorial Plane

    Context: In James Hartle's Gravity, pp. 318-319, Example 15.1, he considers the case of a particle that starts falling from infinity into a Kerr black hole, initially with no kinetic energy (e = 1) and initially moving radially (ℓ = 0). The particle's motion is constrained along the equatorial...
  17. T

    Solid State Book focusing on numerical simulation of quantum systems

    Could you recommend books which covers extensively numerical simulation of quantum system, such as hubbard model, ising model and discuss quantum monte carlo method? Ideally this is a book of condensed matter physics.
  18. DeathbyGreen

    I How can I find the unitary matrix for diagonalizing a Hamiltonian numerically?

    Hi! I'm trying to understand how to diagonalize a Hamiltonian numerically. Basically I have a problem with a Hamiltonian such as H = \frac{1}{2}c^{\dagger}\textbf{H}c where c = (c_1,c_2,...c_N)^T The dimensions of the total Hamiltonian are 2N, because each c_i is a 2 spinor. I need to...
  19. A

    A Verifying Buckling Solution with NDSolve/DSolve

    Hi I am trying to verify my manual solution for this problem by any way, so I tried NDSolve, and DSolve, in mathematica with no success. I don't need it in mathematica I just need any way poosible, even matlab, or any other numeric way/soltuion. Can some one help, or even give me the final...
  20. S

    MATLAB Is MATLAB better for numerical simulation

    From cosmology, the tensor to scalar ratio is ##r=16\epsilon## where ##\epsilon=-\frac{\dot H}{H^2}## is the Hubble slow roll parameter. From warm inflation, $$\ddot \phi + (3H+\Gamma)\dot \phi + V_\phi = 0 ,\quad H^2 = \frac{1}{3M_p^2} (\frac{1}{2} \dot \phi^2 + V)$$ where ##H## is the Hubble...
  21. D

    I Numerical Derivative Formula: X's Not Same Distance

    Hello, What is the numerical formula for a derivative, considering the x's are not in the same distance?
  22. I

    Mathematica Numerical solution of integral equation with parameters

    Hello! Could you tell me about how to take the next numerical calculation in mathematica? (perhaps there are special packages). I have an expression (in reality slightly more complex): ## V=x^2 + \int_a^b x \sqrt{x^2-m^2} \left(\text Log \left(e^{-\left(\beta...
  23. T

    Courses Computational physics course or numerical analysis course

    A question for those who are computational physicist: Dear Computational physicist, I am struggling between computational physics course or numerical analysis. They are both in graduate level (so very intensive), one in physics department and another in math. Both are taught by leading experts...
  24. S

    Mathematica Numerical Simulations with Mathematica: A Beginner's Guide

    I'm very new to Mathematica/programming and I want to do a theoretical calculation using Mathematica, suppose I have, ##Y=CX,~~~C=constant## Now, I want to plot Y vs. X but X should run at every point since every point is a solution for Y, how should I do this? Before, I was thinking maybe I...
  25. A

    I Numerical solution of Schrödinger equation

    Suppose I want to solve the Schrödinger equation numerically for some potential V(x). The easiest way to do so, is to discretize it on a grid of finite length, and apply a finite difference scheme to approximate the second order derivative. Doing so yields an eigenvalue equation on matrix form...
  26. chastiell

    About chua circuit numerical solutions

    hi all ! i'm trying to solve numerically the chua circuit set of differential equations , I am using the equations showed in this pdf: http://nonlinear.eecs.berkeley.edu/chaos/RobustOpAmpRealizationOfChuaCircuit.pdf i have the real circuit mounted and I'm using its parameters for the numerical...
  27. S

    Numerical implementation of a matrix derivative

    Homework Statement Hi all! I'm having trouble understanding the implementation of some derivatives in the expression (1) of this article: https://www.ncbi.nlm.nih.gov/pubmed/26248210 How do I implement ∑(ij) ∂ijw ? Thank you all in advance. Homework Equations w is a square matrix(120x120)...
  28. Telemachus

    Numerical methods for a system of coupled ODE

    Hi there. I have to solve a system of coupled ordinary differential equations. I have some initial values, but in different points of the domain. The equations are all first order. Let's suppose the system looks like this: ##\displaystyle\frac{dy_1}{dz}=y_1+y_2+0.01##...
  29. P

    I Numerical Calculus of Variations

    I attempt to solve the brachistochrone problem numerically. I am using a direct method which considers the curve ##y(x)## as a Lagrange polynomial evaluated at fixed nodes ##x_i##, and the time functional as a multivariate function of the ##y_i##. The classical statement of the problem requires...
  30. vmr101

    Numerical Integration of Chandrasekhar's Equation

    Homework Statement We need to write an integrator for the Chandrasekhars Equation (CE) for White Dwarfs (WD) using python3/NumPy/Matplotlib. We then need to compute the structure of a WD made of our varying elements. We also need to compute and plot the mass-radius relation for WD. Homework...
  31. N

    Compute streamfunction from numerical velocity field

    Homework Statement I have a discrete two-dimensional velocity field (u,v). I want to plot the streamlines by finding the streamfunction ψ and from that plot the streamlines by finding the curves where ψ=constant.Homework Equations In order to find ψ I then have to solve the equations (see link)...
  32. M

    MATLAB How to Define Temperature in a MATLAB Mass Transfer Simulation?

    Hi Guys, I'm trying to do a simple first-order, 1d (x-direction) simulation of mass transfer with the finite element toolbox in MATLAB for the following closed set of equations: (Please note: "X" is not to be confused with the lowercase spatial dimension "x") However, every time I...
  33. Elvis 123456789

    How can I be sure of my numerical result?

    Homework Statement In this problem you will do numerical computer calculations. A skydiver of mass 75.0 kg jumps out of a plane at an altitude of 30.0 km above the surface of the Earth. His parachute fails to open. Assume there is no horizontal motion and the initial velocity is zero. We...
  34. E

    I Decomposing a Function for Numerical Integration

    Is their a tutorial or a reference on how to decompose a function, specifically Fourier and Legendre decomposition, for numerical integration? The method I am going to use for the numerical integration is the Gauss Quadrature, and I suppose I need to decompose my function for the rule to work...
  35. D

    I Applications needing fast numerical conformal maps

    What are useful practical applications of numerical conformal mapping that are most limited by map computation speed or boundary complexity? I'm betting some of the applications will be be physics PDEs, so I chose this DE subforum to ask. As part of an engineering project I've implemented...
  36. N

    Other Numerical programming/modeling jobs with no credentials

    I have a Masters in pure mathematics and wanted to do my PhD in the areas of category theory, homotopy theory, and related fields, but I was not accepted into any programs despite not trying to attempt at all for the "brand name" schools and aiming for what I believed were the less competitive...
  37. F

    A Numerical integration of motion

    Hi,I'd like to build a simulation (realtime) of space ships near a black hole (neutral, still or rotating possibly). Key features would be: 1) the ships are test particles that do not affect the metric a) possibly test rigid-bodies with GR consistent rotational DOF. 2) the ships can fire...
  38. MidgetDwarf

    Courses Good Books for Numerical Analysis & Mathematica for Learning

    I am currently working through Spivak, and have finished Geometry by Moise. I wanted to learn numerical analysis on my own. I could take it at the university, but I rather use the elective for differential geometry. What are good books on Numerical Analysis? I have completed 2 books in Linear...
  39. user123897

    Java Numerical integration of an harmonic oscillator using java

    Hi, I am trying to analyze the an harmonic oscillator using kinematics. first i calculate the force applied by the spring (f = (-x)*k) then i calculate the acceleration (a = f/m) then speed (v= v0 + v0t + 0.5*a*t^2) and finally update x (x = x0+vt) this is a simplfied loop of my program...
  40. awholenumber

    I The algorithms involved in finding a solution with numerical methods

    what are all the algorithms involved in finding a solution with numerical methods ?
  41. awholenumber

    I Few more numerical methods question....?

    i have few more doubts about these two numerical methods type questions ... An equation containing the derivatives of one or more dependent variables, with respect to one or more independent variables, is said to be a differential equation a question usually starts like this ... find the...
  42. awholenumber

    I Differential equations and numerical methods questions

    i have few doubts about differential equations and numerical methods ... in a differential equation question ... you are given an instantaneous rate of change... and you are supposed to find the function that gives , this instantaneous rate of change is this same as ... f(0)=1...
  43. Samia qureshi

    Solve Numerical Problem: Proton Mass, Charge, Speed & Electric Field Strength

    A Proton Of Mass 1.67*10^-27kg And Charge 1.6*10^-19c Moving At An Initial Speed 3*10^6m/s Against A Uniform Electric Field Has Its Speed Reduced By 50% After Covering A Distance Of 1.0cm In The Field. Determine The Strength Of The Field? ‪help me solve this problem what formula should i use to...
  44. Johnny_Sparx

    A Numerical Solution for Complex PDE (Ginzburg-Landau Eqn.)

    I am looking to numerically solve the (complex) Time Domain Ginzburg Landau Equation. I wish to write a python simulator to observe the nucleation of fluxons over a square 2D superconductor domain (eventually 3D, cubic domain). I am using a fourth order Runge Kutta solver for this which I made...
  45. T

    Python Difference in numerical approach for PDE vs ODE

    I think I am missing something painfully obvious, but what exactly is the difference in algorithms used to solve PDEs vs ODEs? For example, I've been looking at finite difference methods and the general steps (from what I've seen, although particular approaches may vary) used to numerically...
  46. Themis

    Numerical methods for system of ODES

    Hi there. I want to evolve a system of non linear coupled ODEs \frac{dx}{dt} = \frac{-k}{x^5(56-y^8)^{9/2}}(85+y^{5} + y^{6}) \frac{dy}{dt} = \frac{-k}{x^4(56-y^5)^{7/2}}(44+y^2) Let's say I have the initial conditions. What numerical method someone could use to solve this? adaptive step...
  47. davidbenari

    I Numerical integration of PDEs: How do you satisfy boundary conditions

    Suppose we are solving a diffusion equation. ##\frac{\partial}{\partial t} T = k\frac{\partial^2}{\partial x^2} T## On the domain ##0 < x < L## Subject to the conditions ##T(x,0) = f(x) ## and ##T = 0 ## at the end points. My question is: Suppose we solve this with some integration scheme...
  48. F

    MATLAB Finite difference numerical integration or ode45?

    I'm trying to numerically solve the time dependent Schrödinger equation and I've been told that the best approach is to numerically integrate using a finite difference method, however I don't understand why I couldn't just use ode45 to solve it?! Is the finite difference (interpolation) method...
  49. ShayanJ

    A Numerical solution of two coupled nonlinear PDEs

    One of my friends needs to numerically solve this two dimensional boundary value problem but has now idea where to begin. Could anybody help? ## [(K H )(f g_x-gf_x)]_x+[(K H )(f g_y-gf_y)]_y=0 #### K H G^2 (f^2+g^2)+\frac 1 2 [KH (f^2+g^2)_x]_x+\frac 1 2 [K H (f^2+g^2)_y]_y-K...
  50. N

    A Numerical solution to SE - variational method, many electrons

    Hi everyone, I am trying to find electron wavefunction of a system I am working in. Numerical method I choose is the Variational method (VM). This method is convenient to find the ground state of the system. More details are available here. Problem I have can be explained on a very simple...
Back
Top