Questions tagged [numeric]
This tag is for questions concerning problems using numbers which either cannot be exactly solved, or where the exact solution may be much more difficult to acquire than by using numerical methods.
numeric
2,631
questions
1
vote
1
answer
45
views
CFD Navier-Stokes Equation in Julia
so below is the code snippet i have for Julia:
using Printf
using Plots
gr()
# Parameters definition
Ny = 21 # Number of points in y-direction
Aspect_ratio = 10 # Ratio of ...
- 11
-3
votes
1
answer
79
views
How to Display All Repetitive Digits from a String ? in vb.Net
String = 24-06-1966
repetitive Nos to be displayed 6, 6, 6
Non-Repetitive Nos to be displayed 2, 4, 1, 9
Hello
If someone can help me to get or displayed Repetitive digits from Numeric String
...
- 11
1
vote
1
answer
29
views
R issue with reshape, reshape is not ordering columns correctly
I am trying to use reshape function in R to arrange my data timepoints in a table. The variable that I am using to split it is numerical, but when reshape arranges the table it incorrectly puts 2,0.5,...
0
votes
1
answer
61
views
How to evaluating solutions to Coupled Nonlinear Elliptic ODEs with Relaxation Method?
I would like to determine the following system of coupled, nonlinear, elliptic ODEs of second order with boundary conditions f(0) = h(0) = 0, f(1) = h(1) = 1.
I used a relaxation method to solve the ...
- 45
0
votes
0
answers
27
views
GA4 changing values to numeric changes the values
Bascially, i have a code that filters the data coming from the API. The data is reasonable, however, the values of the active Users are in string format. Once I changed them (to integers), my max ...
- 11
0
votes
3
answers
93
views
running sum of np.array with widely varying elements
I need to calculate the running sum of np.array. Let's say a is a given np.array of length l and n is an integer step, then I need an array b of length l - n + 1, where
b= [a[0]+a[1]+...+a[n-1], a[1]+...
- 1
1
vote
1
answer
52
views
Byte size of numeric(precision, scale) in Postgres
Given that the size is variable, I am trying to calculate the average cost of a numeric(p, s) attribute. In my case, numeric(10, 2).
From what I understand of the Postgres documentation, this means I ...
- 107
0
votes
0
answers
14
views
error bound for linear interpolation of lipschitz
Let f be a Lipschitz function. Do we have any error bound for its linear interpolation?
Any reference is appreciated. We do not know whether f is differntiable, all we know it is convex in a compact ...
2
votes
1
answer
114
views
Solving coupled 2nd order ODE, numerical in Python
I would like to solve the following DGL system numerically in python:
The procedure should be the same as always. I have 2 coupled differential equations of the 2nd order and I use the substitution g'...
- 45
2
votes
1
answer
34
views
Problems to solve non-linear coupled dgl in python (numerical)
I have the following problem. I would like to solve the following DGL system numerically in python:
$$
\begin{align*}
&g'' + \frac{2}{r} g' - \frac{2}{r^2} g - \frac{3}{r} e g^2 - e^2 g^3 - \frac{...
- 45
0
votes
0
answers
18
views
Custom Riemann solver
I have written my own Riemann solver for a specific problem.
Unfortunately, I am unable to update the solution over time and create a simulation using PyClaw. I am quite new to PyClaw and have tried ...
1
vote
2
answers
115
views
How to prevent the program from returning 'inf'?
I am working on a famous classical physics problem: - the three body problem. I have made the follwoing program : -
#include <math.h>
#include <iostream>
using namespace std;
class ...
- 31
0
votes
0
answers
54
views
Apply Crank-Nicolson method to wave equation with np.linalg.solve
I want to solve a system of equations, where x,y are the vectors which I want the solutions. And c,d are the solutions. A,B are matrix
x-y=c+d
y-Ax=Bd+c
The full problem which I tried to summarize ...
0
votes
2
answers
103
views
RAML validation for json array
In my API RAML, there is a query parameter named 'sfIds' which is an array type. I need to implement validation within the RAML to ensure that the array elements are always numeric, such as [111, 222, ...
- 685
1
vote
1
answer
61
views
Multiple polynomial regression in C#
So I need to fit some vectorized data into a 3rd degree polynomial, however I can't find any libraries in C# that are able to do that.
Essentially, x is a vector with 3 elements ([R, G, B]), and the ...
