# Questions tagged [numerics]

Questions on the numerical functions of Mathematica, implementing numerical methods and numerical computing with Mathematica.

1,663 questions
Filter by
Sorted by
Tagged with
16 views

39 views

### WhenEvent doesn't work as expected when the condition is satisfied in the first step

I have noticed strange behavior of WhenEvent in the case where the body of WhenEvent is satisfied in the first step. For example, ...
120 views

### Wish to compute ln(x) with millions of digits of precision fast as possible

Computing $\ln(10)$ to 6 million digits of precision on my 2.5 GHz machine running Mathematica 12.1 takes about 23 seconds using the methods below. Wish to compute $\ln(x)$ with much higher precision....
107 views

61 views

### Error in solving a system of partial differential equations

I'm trying to a solve of system of partial differential equation, but Mathematica is giving some error. Can anyone help me please to find out the error. ...
38 views

### Numerical Evaluation Error

Could anyone explain why the evaluation of this gives a weird error? a = 1.11111111111111111111; Do[a = 2 a - a; a, 50]
101 views

### How to solve the following delayed differential equations with periodic delay effect?

I want to solve the following differential equations $\partial_{t} f(t) = - a f(t)-a \sum_{n=1}^{N} f(t-n \tau) \cdot \Theta(t-n \tau)$ I learned the way for solving the equations from the following ...
80 views

### Smoothen the result of FindRoot

I have a set of code for which it involves finding the corresponding c for each a (although I will give a value of ...
89 views

### Why is Mathematica saying this sequence tends to $0$?

I am a complete novice in Mathematica so please bear with me. I am trying to graph a sequence that converges to $\pi$ but after $27$ iterations Mathematica just goes crazy and I am not sure why. I got ...
75 views

57 views

### NDsolve Boundary Condition is a Function of the Solution

I am trying to solve something like Fick's Law using NDSolve: $$\frac{\partial \varphi}{\partial t}=\frac{\partial^2 \varphi}{\partial r^2}+F(r,t)$$ Subject to a ...
32 views

I have some complicated function that depends on a few parameters that I need to integrate. It is integrated in the fastest way by using "AdaptiveMonteCarlo" method. However, I have found ...
55 views

### Significant digits

I have a rather silly question, so please excuse me=) Let's say I have a general Mathematica code, where I numerically evaluate and combine several quantities. I would like to know how to determine ...
402 views

### Nonlinear dispersal equation modeling insect aggregation

I'm a newbie with Mathematica, I know it's a basic answer, but I can't solve the problem on my own. I have the following equation reflecting insect aggregation at low population densities (taken from ...
75 views

### Solving the PDE $\partial_t u = \partial_x (u^2 \partial_xu)$

I'm trying to use Mathematica to solve the following equation $$\partial_t u = \partial_x (u^2 \partial_xu)$$ with $$u(0,t)=u(1,t)=0$$ and $$u_0(x)=\sin(\pi x)$$ in order to check a numerical method I ...
I want to use FindRoot for a 3-variable equation to make sure if there is a root around the point $\{x,2.356\},\{y,0.2\},\{z,0.802\}$ ...