Answered
Why does my nonlinear (exponential or trigonometric) model fit poorly?
Suppose I wish to fit some data to a simple exponential model. I'll make up some data, then add moderate noise to the data. X ...

5 years ago | 0

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Question

Why does my nonlinear (exponential or trigonometric) model fit poorly?
This is a question I see often online by users of curve fitting tools. Typically, I see someone try to use a tool like the curve...

5 years ago | 3 answers | 2

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Answered
i have a problem with my plot, i am not getting any values and the system gives me an empty plot.
Look at what you did. a = 0;5; First, maybe you think this creates a vector in a? Instead, it just sets a to 0. Then it dumps...

5 years ago | 1

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Answered
How do I use multi-parameters in my optimization problem for fminunc?
No. It won't look like that. fminunc cannot somehow magically know how you intend the inputs to be used. Computers cannot read y...

5 years ago | 0

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How to find a limit without syms and limit function
You can use my limest function. It is on the file exchange. >> fun= @(x) (x.^3 - 1)./(x-1) fun = function_handle with value...

5 years ago | 0

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not getting left eigen vector
If you want the set of left and right eigenvectors, we see in the help for eig... [V,D,W] = eig(A) also produces a full mat...

5 years ago | 0

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Answered
Optimization of a series of linear equations to maximize profit
They are not differential equations. So I'm not sure what you were possibly thinking. They are LINEAR equations. But you do no...

5 years ago | 0

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Approximate dots area by circle and define its radius
You cannot do anything until you decide what you need to do. You say to need to approximate it with a circle. If the circle wer...

5 years ago | 0

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plotting number bigger than double realmax
If your numbers are greater than realmax, then you can't. Period. You cannot represent a number greater than realmax. You cannot...

5 years ago | 0

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How do I calculate a logarithm of a variable base?
Just write your own function. Save it on your search path. Now you have it. [log(10),logb(10)] % natural log [log10(5),logb(5,...

5 years ago | 1

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How to read a very large number, say of 700 digits?
You don't understand. A 700 digit number is not representable in double precision. Even if it were, then roughly 684 of those di...

5 years ago | 1

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Answered
How to obtain the 3 × 3 symmetric covariance matrix of a 3x1 matrix?
If all you have are three numbers, then a covariance matrix is meaningless. There are two cases we might consider, since I have ...

5 years ago | 0

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How to plot three variables in matlab?? A*cos(w*t+theta)
It certainly is possible. All you need is a multi-dimensional holographic monitor to view it. Sadly, these are hard to come by, ...

5 years ago | 2

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Answered
Stop Bit growth for power computation
Case 1: You CANNOT raise a double precision number to a power such that it exceeds flintmax (2^53 - 1) and expect the result to ...

5 years ago | 1

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Unable to find solution to matrix using Gauss Seidal code. How should I proceed to get the solution?
By the way, the name is spelled Seidel, not Seidal. https://en.wikipedia.org/wiki/Gauss–Seidel_method A=[-0.707 -1 0 0 0 0 0 -...

5 years ago | 1

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Answered
Is there any alternate ways to make payment while registering for MATLAB associate certification
This is not a question for Answers, but a question to pose DIRECTLY TO THE MATHWORKS. Answers is a user supported site. We are a...

5 years ago | 0

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Answered
Writing a math equation.
Good. You made an effort, did some reading. Not only that, but you are trying things, getting your hands dirty. Keep that up and...

5 years ago | 0

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Answered
How to determine the coefficient from the argmin function ?
What you need to unerstand is there is NO simple solution. There are no unique set of values a1, b1, c1 that solve the problem. ...

5 years ago | 1

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Solve Equation which has 2 solutions but returns imaginary numbers
Super-complicated? Seriously? :) NOT. But I suppose complexity is in the eyes of the beholder. Start with this: Theta=[ 15] T...

5 years ago | 0

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Unique values for each sequence
Hint: What does diff give you? TRY IT! x = [1 1 1 1 2 2 1 1 1 3 3 3 2]; diff(x) What would happen if we tried find on that re...

5 years ago | 2

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Hi Guys.. I need to print X values from intlinprog output from all 24 iterations as a matrix, when am trying to assign the values to A matrix its not happening. PLz help
Of course, we cannot answer your question in more depth, since you have not provided your data. But if we look at the screenshot...

5 years ago | 2

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normpdf is taking zeros
No. At least, not in double precision. The "exact" value there is impossible to represent in a double precision number. The nor...

5 years ago | 0

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Answered
How to reduce computation time with 8 nested for loop
This is why there are optimization tools provided. Use them, instead of brute force search. But really, this is a combinatorial...

5 years ago | 0

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How to put vector components into one single matrix and instead having them appear as two separate arrays
A very confusing question. But what about this does not do as you want? syms x y A = [2*x 1; 2 x*y] Admittedly, that is as sh...

5 years ago | 2

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How to find the exact answer of an exponential equation?
syms t real Eqn = exp(-0.04*t)+exp(-0.12*t) - 1; Write it like that. I did so because now we can plot it. See that I specified...

5 years ago | 0

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Increase arithmetic precision in using Cardano formula
Either use roots to solve for the roots of the quartic, or be forced to use symbolic form for the solutions. Note that roots wil...

5 years ago | 0

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Chosing the step between lower bound and upper bound in genetic algorithm
Actually, this is simple. even trivial. Can you force a variable to take on integer valiues in GA? (yes) In the help for GA, I...

5 years ago | 0

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how to find the root of function?
Or do this: alpha=0.74; g =0.5; gamma=1.2; sigma=1; phi=0.8; epsilon_1=1.5; w_r= (epsilon_1-1)/epsilon_1; syms n_h a ...

5 years ago | 0

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Optimizing 1 equation with 7 variables
You do understand this is likely impossible to do? If there are ANY solutions which satisfy the given equality, then there are ...

5 years ago | 1

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Answered
Collatz Conjecture using for loop
Your code is close to a working algorithm. There are some issues truly good code would worry about. Could you ever have an over...

5 years ago | 3

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