# All Questions

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75 views

### SetOptions not persistent between sessions

Let's say I decide I want all my axes to be colored red, so I do SetOptions[Plot,AxesStyle->Red] For the remainder of my session, I correctly get ...
61 views

### How to code Newton's method [closed]

I need some help with Newton's method in mathematica. Yes, I know that many questions have been asked about Newton's method, but I still don't understand I have to write a simple code for Newton's ...
286 views

### Generating large quantity of random numbers from an exponential distribution with fixed sum

I am trying to generate a large number (approx. 2 millions) of random numbers from an exponential distribution of the form: $$D(t)=\exp(-3000\, t)$$ The sum of the numbers must be 40. I use the method ...
63 views

### how to plot multiple plots sharing a common X-axis and Y-axis

With the following Code, I generate various ListLinePlots but I like to create the example ...
60 views

### why this analytical formula can't yields the answer of numerical integration?

I have an initial function as follows ...
75 views

### Dataset division by dataset subtotals

I have the following dataset: ...
54 views

### Single computation is fast, but 6 computations are extremely slow

I have an expression that involves many Sign functions. I want to expand this in the piecewise format. My function is: ...
48 views

### ExampleData problem

When running : iris = ExampleData[{"MachineLearning", "FisherIris"}, "Data"]; I get the message : ...
51 views

### NDSolver cannot give precise result for extremely small values

I would like to solve an ODE with MMA. The equation is simply the Coulomb law. However, I cannot get a satisfying result: ...
119 views

### Is it possible to simplify this expression in Mathematica?

Let us consider an expression $$\frac{\sqrt{\sqrt{2-x^2}+x} \sqrt{1-x \sqrt{2-x^2}}}{\sqrt{1-x^2}}.$$ Its plot ...
837 views

### Getting rid of the horrible Times x in Mathematica 12.3

Revised question to reflect new issues pertinent to Mma 12.3 and that are unresolved by the linked question - this is NOT a DUPLICATE and should not be reflected as such As of Mathematica 12.3, if I ...
39 views

### Can I set the limits of NIntegrate symbolic in a multidimensional integral?

I have written my integral as follows: NIntegrate[ f[re, rp, r], {re, 0, \[Infinity]}, {r, 0, \[Infinity]}, {rp, RealAbs[re - r], re + r}] but it returns ...
61 views

### How to show the excluded region in a scatter plot using margin or something else in mathamatica?

Here is my scatter plot I want show that the region lying in the range [Delta]=(0,40) and [Delta]=(140,190) is excluded. How do I show that? The code for my scatter plot is given below ...
244 views

### Any Mathematica techniques to calculate time takes to reach the equilibrium of a PDE solution

I am solving this PDE numerically (dimensions: spatial variable x and time t). I know how to solve my problem numerically (for a given range of time). The solution reaches its equilibrium after a ...
184 views

### How to minimize a function involving NIntegrate?

I have three datasets as follow: ...
19 views

### SetOptions error message upon launching Mathematica v.12

When launching Mathematica v.12, before opining any notebook, I get the following message: It does not afffect the execution of my notebooks, but it is annoying and I would like to understand how to ...
51 views

### Dealing with covariant derivatives (xCoba)

I do not understand why the output of the two commands: ...
78 views

### Stiff system problems with NDSolve

I'm trying to solve the two order differential equations using NDSolve. Here is the code: ...