Questions tagged [equation-solving]
763 questions
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Iteration in Matlab
I want to solve some iteration in chemical engineering problem using matlab.
So the problem that I want to solve is Calculating the inter convertion of series adiabatic reactors, here is the algorithm given:
Algorthm in reactor 1
Algorithm in…
yolabertilsyahendri
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1 answer
Solving an equation containing absolute value, with python 3
I'm trying to solve the following equation, with python 3.6.3:
I did
from sympy import *
x = Symbol('x', real=True)
solve(abs((abs(x**2-1)-x))-x)
but I get the following message:
Traceback (most recent call last):
File "", line 1, in…
Luo Kaisa
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Symbolically solving equation for a given variable in Maxima
I can solve an equation using Maxima by using the commands below.
kill(all);
A:A; phase:phase; solve(A*cos(2*pi*f*t+phase)=y,phase);
And it gives me the correct answer.
phase=acos(y/A)-2*f*pi*t
But when I try and solve for just the top portion of…
Rick T
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Solving system of linear equations in a subclass using inherited variables
I am trying to solve a system of linear equations in a subclass using inherited variables from multiple parent classes. The system contains 4 equations and 4 unknowns. Without including the long equations of what I'm working with, f(variable) means…
Dimethyltrypper
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0 answers
Zeroes of a Function in a Range in PARI/GP
I'm trying to find the zeroes of functions within the range [0,1]. My functions are generally looking something like this:
F(t)=2*sin(8*Pi*t)+2*sin(2*Pi*t)-1
The naive method I've tried so far is getting a very crude plot of the function into Pari,…
Mystery_Jay
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1 answer
Restricting domain of solution set when using SymPy solve in the multiple variables case
Say, I'm trying to solve the system of equations:
for θ, λ and ɸ , where a, b, c and d are complex numbers and the matrix on the LHS is a unitary matrix.
The SymPy code I have at hand does successfully do the job but there are a few edge cases it…
user10648668
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2 answers
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 sequence of equations where each time I have one variable…
Rohithsai Sai
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1 answer
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 solve this in MATLAB?
shilpa prakash
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2 answers
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 ?
I could solve them on pen and paper finding the…
Anuradha
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4 answers
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 Vx
ex:
V1 xor V2 xor V3 = 1
V1 xor V2 = 0
V2 xor…
Gary Poc
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0 answers
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 the equations I get no problems. I define the…
Riccardo
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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 for the above example is x = sqrt(-1/-C)
I tried…
symbolrush
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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 variables (x, y ,z ...) which satisfies these…
EagleOne
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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 interested) in code and need to rearrange/solve that…
albert
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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 - m1 * AA == 0, (fp * BB * P)/ep - f1*AA*P - mp *…
Rspacer
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