# Questions tagged [equation-solving]

The equation-solving tag has no usage guidance.

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**2**answers

31 views

### Find maximum value of a function for a constrained boundary variable using Matlab or Matlab symbolic tool?

I am currently solving equations and I need to find the maximum value of a function.
The equation is
v = sqrt(u^2+2*a*s);
where 0.1 <= a <= 1.5 and
u = 2.75;
s = 3.194;
I have to solve a ...

**0**

votes

**0**answers

11 views

### Needing help on the optimization of the solving of a set of non-linear equations that Sympy struggles to do

I am a beginner in Python, and a complete newcomer in Sympy. For a school project, I want to simulate a (surprisingly) complex movement. I have found 4 equations that I need to solve.
The equations ...

**-3**

votes

**0**answers

39 views

### Solve an equation with three variables in python? (only one equation available)

I want to solve the below equation using Python and any possible Library.
y = c / ((x-α)^β)
Variables are: α, β and c.
I know this equation may have many possible answers, I want to calculate all ...

**0**

votes

**1**answer

25 views

### How to return a finite (float) value with nonlinsolve in SymPy?

I am very new to programming, and had to use sympy for a school project.
I think I get that using nonlinsolve to return an angle gives an ImageSet with the angle + 2n*pi. However I want it to return ...

**0**

votes

**2**answers

30 views

### Find solutions of a system of equations as close as possible to the previous solutions

Currently I am using the vpasolve command to solve a system of 3 equations with 3 unknowns in it. These 3 equations are being used to model the kinematic motion of a robot manipulator, and the ...

**0**

votes

**0**answers

42 views

### Non homogeneous heat equation

I have this code which solves the heat equation with non homogeneous boundary conditons:
$$u_t=ku_{xx}$$ where k is the diffusion coefficient
but now I want to add a constant which makes the equation ...

**0**

votes

**1**answer

40 views

### Solve complex matrix equation

I have a complex equation involving matrices:
R = expm(X)*A + (expm(X)-I)*inv(X)*B*U;
where R, B and U are known matrices.
I is an identity matrix.
I need to solve for X. Is there any way to ...

**0**

votes

**1**answer

39 views

### Solve a Quadratic Equation in two variables using Python

I have got two equations, one linear say,
, where m and c are constants
and the other quadratic say,
, where x1, y1 and r are constants.
Is there a way I can solve for x and y using Python ?
...

**1**

vote

**4**answers

55 views

### Which algorithm to solve a system of equations where variables are bits and operation is xor?

I'm trying to solve a system of equations. Each equation is in the form:
V1 xor V2 xor ... xor Vx = Sx
Vx and Sx are single bits variables.
The Sx are known and I need to find the value of all the ...

**1**

vote

**0**answers

52 views

### Wolfram Mathematica Solve command for a nonlinear system of equations

I am trying to solve a nonlinear system of equations by using the Solve (and NSolve) command, but the evaluation get stuck.
For a very similar system, basically the same but with the derivatives of ...

**1**

vote

**1**answer

42 views

### Solve nonlinear equation symbolically in R with `Ryacas` package or an alternative

Out of pure curiosity I'm interested if there is a function/package that allows to solve simple nonlinear equations in R?
Let's say I want to (symbolically) solve 0 = C + 1/x^2. The expected result ...

**0**

votes

**1**answer

37 views

### Time varying input ODE solving

I'm trying to solve a set of ODE equations using ode45. A number of my parameters are already a function of time but I keep getting errors.
function odo
dx(1,1) = (vl+vr)/2*cos(x(3));
dx(2,1) = (vl+...

**0**

votes

**0**answers

33 views

### How can I solve an unknown parameters between two equations in r

I have a problem.
I have two equation like this.
I want to take two parameters : N and n.
Please, tell me how can get the parameters.

**0**

votes

**0**answers

50 views

### How to calculate vector U from this equation? [duplicate]

I have this equation:
P = K*U
P & U are vectors with 6 arrays & K is a 6*6 matrix.
Arrays of U are unknown & I want to compute them but don't know how to write the code.
K= [38.25 9....

**0**

votes

**0**answers

34 views

### Solving equations programatically [duplicate]

My project: I want to develop a library that would solve equations. For example: Given input "3x+5=-1" I would like the output x=6
Why? Just for fun, I am learning and am interested in this topic.
...

**0**

votes

**1**answer

69 views

### Solving n linear systems efficiently

I have n (very large) independent linear systems (Ax = b_i). They all have the same A, but b_i is different for (i = 1, ..., n). I want to solve these n systems in parallel in CUDA.
I was thinking ...

**2**

votes

**2**answers

50 views

### Finding the odd point in a dataset without using loops

I am given a set of points (p1,q1) (p2,q2) ... (p20,q20) which satisfy the function q = 1/(ap + b)^2 except that one of these does not satisfy the given relation. The values of a and b are not given ...

**0**

votes

**0**answers

25 views

### How to solve overdetermined quadratic system in Circle Packing

I'm working on a program where I have to satisfy an overdetermined system of non-linear equations.
Basically, the program will add points dinamically, and every new point must be added where it ...

**0**

votes

**2**answers

105 views

### How to solve a linear system of a square matrix in C++ when the matrix has no LU-Decomposition?

I have been trying to develop a program to solve a system Ax=b for a square matrix A using LU-Decomposition. However, I realized that this decomposition does not always exist (one way to tell is if a ...

**2**

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**0**answers

48 views

### SymPy: solving overdetermined system of linear equations

I know that SymPy is able to solve overdetermined systems of linear equations, but I'm running into the following problem:
Let's start with something that works:
from sympy import *
x, y, z = ...

**2**

votes

**2**answers

29 views

### Trying to Convert Excel Equation to C#

I've got this Excel equation and I'm struggling to convert it into c#.
The "to the power of" and "log" parts are tripping me up.
The excel equation is as follows:
LOG((10^(PreSkillRating/400)/((-...

**4**

votes

**1**answer

48 views

### How to find the unique solution to norm(a,2)==c; when c is a scalar and a=[x abs(1/x);x+1 1/x]

I am trying to find the unique solution to the following equation using Matlab
norm(a,2)=0.11
when x is a variable and a=[x abs(1/x);x+1 1/x]. b is the exact formulation of norm(a,2),...

**0**

votes

**1**answer

53 views

### Haskell: How to find the number of integer solutions to equation for use in Sieve of Atkin?

I am currently trying to implement the Sieve of Atkin in Haskell
In step 3 on the Wikipedia article on the Sieve of Atkin I need to find the number of Integer solutions to multiple equations.
...

**0**

votes

**0**answers

14 views

### Q: WxMaxima trig system of equations gives [] as result

I just started using WxMaxima and cannot get a solution to the following system of trig equations.
Provided that alpha and beta are the only 2 variables in a system, how can I get the solutions in ...

**-3**

votes

**3**answers

55 views

### Iteration for x value in equation

I've been set a task to iteratively calculate the value of x of the given formula : x3 - 3x + 4 = 0** using trial and error.
The code will first plug in -1.5 as its first guess and then work up or ...

**0**

votes

**2**answers

88 views

### Solving a linear system of equations

I am working on using the finite element method to calculate heat flow through elements.
I'm currently stuck on solving a system of equations where there is variables on both side of the equality. A ...

**1**

vote

**1**answer

70 views

### Solve a system of boolean equations in Matlab

I have a set of boolean equations, i.e.
var1 = x AND y
var2 = x OR z
var3 = ...
var4 = ...
And the constraint that every output vari should equal 1.
I want every corresponding combination of input ...

**-1**

votes

**1**answer

29 views

### How to solve z = (((m / k) / j) / x) for x optimizing z towards 2ˣ

So say I have these variables:
m is the amount of memory available in bits
k is a dividing factor
j is another dividing factor, kept as a separate variable instead of combining with k
x is the value ...

**0**

votes

**1**answer

35 views

### How to generate an equation as a function of a specific variable from a set of symbolic equations?

after some search in the forum, I couldn't find the answer to my question.
Problem: I have a set of symbolic equations (more than 10). For simplicity reasons, let's say that my goal is to write the ...

**2**

votes

**1**answer

89 views

### What is the best way to solve a system of linear equations with infinite solutions?

I want to solve a system of linear equations (SLE, Ax=b, where A consists out of 8 rows and columns) but this system will always have infinite solutions. Many people refer to Eigen, when it comes down ...

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**2**answers

46 views

### Solving a 2-Variable function to only 1 of the variable doesnt work on arrays

I have found from StackOverflow how to solve a fucntion with two variables giving the one as constant/known.
This is the part of the code:
def R(gg,a):
return a-r0*g0**(1/2)*D(gg)/gg**(1/2)
def ...

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votes

**0**answers

19 views

### How to solve linear systems that have probabilety variables with SymPy?

So say I have a simple system of equations:
x + y = 5;
y * x + P * x = 3;
And P is a variable that has some given, known distribution. I would like to solve this system for x and y relative to given ...

**3**

votes

**1**answer

119 views

### Solving multivariate equation for a subset of variables

I am using sympy to solve some equations and I am running into a problem. I have this issue with many equations but I will illustrate with an example. I have an equation with multiple variables and I ...

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**0**answers

67 views

### how to circumvent the 'singular matrix' error when numerically solving a multivariate system of equations using R rootSolve::multiroot

My system of equations contains an ifelse condition; I don't know if that is what's causing the singular matrix issue, because it sometimes works and sometimes doesn't work.
This works:
zf <- ...

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vote

**0**answers

84 views

### How to solve function f(x,y) for either x or y (if the other is given)?

I started to work with mathjs and tried to rewrite some Python code using sympy for algebraic calculations. I implemented a fit function I got from a research article (see link in code snippet if ...

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vote

**1**answer

50 views

### Solve simultaneous equations using Ryacas package (OldSolve) in R

I am trying to solve a system of 3 equations using Ryacas package in R.
library(Ryacas)
yacas("OldSolve({(f*Reg/(k + Reg)) - r*BB - ab * BB - a1*f1*BB*AA*P - fp*BB*P==0,(ab * BB + a1*f1*BB*AA*P)/e1 ...

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votes

**0**answers

112 views

### Solve simultaneous equations in R with variables

I need to solve a system of four equations and solve for (Alg,Blg,C,D)..the others are simply variables.
dAlg = (ab*D + a1*f1*D*Alg*Blg + a2*f2*D*Alg*C)/e1 - m1*Alg;
dBlg = (f11*D*Blg)/eB - f1*Alg*...

**-1**

votes

**1**answer

47 views

### 10,25,50,100,250,500,1000 how to find this sequence equation to plot in a graph

10,25,50,100,250,500,1000..... How to find above number series equation.
I need to generate the number pattern like above to plot it in my graph.
I tried like 2x, 2x, 2x + x / 2, 2x, 2x, ..... 2n, ...

**0**

votes

**1**answer

53 views

### How to solve equation with rotation and translation matrices?

I working on computer vision task and have this equation:
R0*c + t0 = R1*c + t1 = Ri*c + ti = ... = Rn*c + tn ,
n is about 20 (but can be more if needs)
where each pair of R,t (rotation matrix and ...

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votes

**1**answer

37 views

### get random number of parameters that satisfy given equation in Python

I'm new to Python and I would like to get 1000 of parameters that satisfy a given equation.
More precisely, below is the equation of the sphere, assume the position of the sphere center(x0, y0, z0) ...

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vote

**1**answer

52 views

### Scipy equation system with multiple equations

Hello I have a problem using Scipy's fsolve function when I have an equation system.
My code only let's me have as much variables as there are equations in my system, but we all know that in practice,...

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vote

**2**answers

88 views

### Solve A linear equation system b=0 Rstudio

i would solve a linear equation system like this:
x_1*3+x_2*4+x_3*5+x_4*6+x_6*2=0
x_1*21+x_2*23+x_3*45+x_4*37*+x_6*0=0
x_1*340+x_2*24+x_3*25+x_4*31+x_6*0=0
x_1*32+x_2*45+x_3*5+x_4*6+x_7*2=0
x_1*9+...

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votes

**2**answers

160 views

### Linear equation with 3 variables in C

I am given my C class homework, which is:
A hyperloop track is built of individual pipe segments of certain length. The track starts and ends with a bulkhead, and there is a bulkhead in-between ...

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**2**answers

54 views

### Solving system of equations on MATLAB, when a constant exists in variable matrix?

How do I solve the following system of equations on MATLAB when one of the elements of the variable vector is a constant? Please do give the code if possible.
More generally, if the solution is to ...

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votes

**0**answers

31 views

### Solving for power of a non linear equation in matlab

I have been trying to solve for n in the equation given below in matlab. All the rest of the values are known :
H_obs = 1*61 vector, dhdx = 1*61 vector, a = 1*61 vector. All the values of all the ...

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**0**answers

19 views

### Solving two nonlinear equations with nsolve

I am trying to solve two long nonlinear equations simultaneously using nsolve. I am getting a ZeroDivisionError, and I think this is because I have not set an initial guess for either variable. In the ...

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vote

**2**answers

133 views

### Eliminate a variable to relate two functions in Python using SymPy

I have two equations that are parametrized by a variable "t". These look like:
X = p(t)
Y = q(t)
where p and q are polynomials in t. I want to use Python's SymPy library to eliminate the t variable ...

**0**

votes

**0**answers

13 views

### I would like to find all roots of a nonlinear equation in one variable, e.g., f(x) = 0

I would like to find all roots of a nonlinear equation in one variable, e.g., f(x) = 0.
The maximum possible number of solutions can be determined theoretically.
The unknown variable x is an angle, ...

**1**

vote

**2**answers

65 views

### Finding the root of an equation using iteration

I am attempting to find the root of the equation 3x3+x2-10 using iteration. Here is the code that I have so far, however I don't think I have implemented the while loop correctly since it the equation ...

**0**

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**0**answers

22 views

### Alternative to vpasolve and results arrangment

I'm triying to solve the following problem in Matlab:
I have two known matrices F and Q mxm (m=20), and I want to find a matrix L that satisfies the equation
F-(QL+LQ)/2 = 0
(I know it is a ...