# All Questions

31 views

### NIntegrate/NSum with parameters [duplicate]

I'm trying to calculate a continuous integral within a discrete integral. Something similar to this (yet more complex): ...
62 views

### Scaling the x-axis in ListLogLogPlot[] or ListLogPlot[] in lieu of DataRange

I will present my existing workaround but I am wondering if there is a better solution that takes less time (my solution seems to ~double the time it takes to produce the desired plot). Using ...
85 views

### NDSolve diffusion equation over/underdetermined

I have a feeling the solution to my problem is very simple… but my knowledge of differential equations is pretty weak. I am trying to solve a scalar diffusion equation (used in NMR spectroscopy, but ...
105 views

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64 views

### Given a list of date and value pairs, efficiently sum the values by date

I have a list of date & value pairs. There can be multiple entries for each day. Sample data can be generated with the following: ...
30 views

### Expressions like <<1>> [duplicate]

In a function where I call the Maximize function, I am getting an error that says ...
108 views

### DAE - varying initial conditions

I want to solve a DAE-system and I want to vary more than one initial conditions and to manipulate them. I looked here: Putting NDSolve into ParametricPlot But it does not work: ...
60 views

### Importing images from the web using ImportString & URLFetch

I can bring images from the web using the Import command like this: Import["http://blog.wolfram.com/wp-content/uploads/2008/06/se-30.jpg"] Sometimes the web ...
95 views

### I am missing a function like HoldPattern

Temporary message: I am planning to edit this question, making the examples less confusing and by moving the things that are confusing to a separate question For any confusion about expressions that ...
66 views

### Integrate of Heaviside Function returns an error answer

I try to evaluate an Integral of a Heaviside function, but it turns out with an erroneous output(zero). Here is my integral: ...
78 views

### Reversing the ColorScheme used in an ArrayPlot and setting the font size in the color bar

I have a matrix of data that I am plotting via ArrayPlot. ...
421 views

### Finding areas of beings in microscopic image

I've got lots of images of diatoms. I need to get a list of their equivalent radii. It's not crucial to get them all, as long as those missed don't mess with the radius distribution (as would ...
133 views

### Making large tables easy to read with frozen headings and scrollbars [duplicate]

I would like to represent a table containing a large amount of information in such a way that I can (a) use scrollbars and (b) have table headings that don't scroll off the screen [just like the Free ...
169 views

### Common subexpression from two expressions

I am working with some unpleasantly tedious polynomials, which need to be manipulated in various ways (integrate with respect to some variable, differentiate with respect to another). Since these ...
69 views

### How can I change the Graph required data such as EdgeWeight,VertexWeight,EdgeCapacity,VertexCapacity in the Graph?

I asked this question in different form and because I couldn't receive the proper answer so I have to change my question.I know that was my fault sorry.I need to change the Matrix Data of nodes and ...
66 views

### Exporting plots

I want to export a plot which includes curve fitted to a multiple data set. shortly ( I use autolegend function Here ) ...
99 views

### The plot of roots of polynomials

I have polynomial equation like Tribonacci Polynomials for example: $T_3(x)=x^4+x$. After finding the roots of this polynomial, I want to show these roots in the complex plane. I have tried lots of ...
48 views

### Table of Polynomials [closed]

I made a function makePolynomial that creates a random Polynomial of a certain degree, e.g. 2+T+3T^2+8T^3-5T^4... now I ...
106 views

### Symbolic integration in real domain only ( assumptions and ComplexExpand don't work)

Integrate[m^2/((x - m^2)^2 + y^2), m] mathematica gives me a complex-valued reuslt, but maple 17 gives me what I want. I tried using assumptions, but it doesn't ...
98 views

### Safe values of $\mu$ and $\sigma$ when randomly sampling from a Log-Normal Distribution?

I believe I'm obtaining overflow errors when randomly sampling from a log-normal distribution with the command: RandomVariate[LogNormalDistribution[μ, σ], 1] ...
113 views

### Computing Correlations and p-values

I have two vectors $A$ and $B$ of length (say) $50$ or so, and I want to determine whether there is any correlation between their entries. I computed their correlation directly and found it to be ...
42 views

### Collect and factor equations with certain terms

Collect user defined terms from a symbolic algebraic expression ...
86 views

### Computation results returned as image instead of text

Some times my Mathematica return the result of any computation as text, I don't know why, and how to revert it. If I close and open again, it comes back to normal. As you can see, the mouse cursor ...
71 views

### Taking derivative of Euler relation [closed]

I have defined the following function, which is the Euler relation for $\cos\,x$. f[x_] := 1/2*(Exp[I*k*x] + Exp[-I*k*x ] ) I want to take the derivative with ...
213 views

### Simplify — is this simplest result Mathematica can provide?

I have a question about Simplify: When I do a simplification the returned result is not as simple as I want. When I ask for the Norm of an complex expression, ...
61 views

### Maximum root by using FindRoot [closed]

Assume f[x_, y_,z_] := Block[{A}, FindRoot[Abs[r[x, y, z]] - w[z] + 1 == 0, {A, 100}]] where ...
160 views

### Simple problem with Manipulate and Plot

Would anyone have an idea why the following doesn't work: rule = {z -> x^2 + 2 x + y}; Manipulate[ Plot[z /. rule, {x, 0, 10}], {{y, 2, "y"}, 1, 5} ] But ...
125 views

### How to collect/reduce with respect to multiple variables?

I have this code: a == b + c + d - e Is it possible to collect or reduce this expression into this: c + d == a + e - b ...
117 views

### No anti-aliasing on BarChart3D?

If I put AA code in BarChart3D, it won't works. Here is the code. ...
265 views

### Visualizing vector spherical harmonics

I have painstakingly derived the vector-spherical harmonics $\mathbf{V}_{J,\,M}^\ell(\theta, \phi)$, which are the generalization of ordinary spherical harmonics $Y_\ell^m(\theta, \phi)$ to vector ...
9 views

### Fractal Analysis [migrated]

Is there any way to compare two fractals and analyse the difference between the two. I'm doing a project on fractals and It'll be very easy if there is a module which can be used to analyse and ...
83 views

### Compile not correctly initializing a variable defined inside Module

In the following example, inside the minimumX's Module, x is initialized to 1, but the ...
88 views

### How to type function terms into metric?

I submitted my question before on site:Anything wrong with Atlas 2 or Mathematica?. Due to my vagueness, my problems might not be clearly understood. I am trying to solve several functions based on ...
46 views

### Dot doesn't work [duplicate]

I have a problem with the matrix product (Dot). Here is my code: ...
179 views

### Where to begin? [duplicate]

I was looking at the Mathematica website today and just decided to buy the software. I've spent too much time juggling annoying symbolic expressions by hand that actually learning to do things with a ...
103 views

### Numerical sum does not give consistent results

Consider the function ...
162 views

### rotating 3d text

Is it possible to create a 3d rotating text like this: animation here. Here is my try so far: ...
49 views

### LogLinearPlot analog for Plot3D? [duplicate]

Is it possible to make 3D plot in logarithmic coordinates? I need analog LogLinearPlot to plot 3D figure in logarithmic x, or y, or both coordinates.
120 views

### find where 3 inequalities are simultaneously greater than zero

I have 3 functions, f11[l], f12[l] and f13[l], and I would like to know for which values of l these 3 functions are greater than zero. How do I do it analytically or numerically or graphically in ...
77 views

### Tough Inverse Fourier Integral: why does the sign matter?

I'm computing the Inverse Fourier Integral of ((a^2 + omega ^2) c^2) /((b^2 + omega^2) ((r^2 + omega^2 - omegaInt^2)^2 + (2 omegaInt r)^2)) ...
108 views

### Apply a Function Pairwise

I'm new to Mathematica I'd like to apply Mean pairwise to a list to achieve the following. ...
147 views

### Track object movement

Referring to this link I happen to realize that actually the trace being projected is dependent on an equation and not on disk or circle. Though I was presuming that it is getting traced because of ...
131 views

### How can I give graph required data with GUI?

Consider that I have the simple graph of ...
76 views

### financial data behind Wolfram|Alpha and Finance Platform

I need to price 23,000 securities from 1999 to 2007, and they are surprisingly hard to find on subscription-based services, like Bloomberg LP, ThomsonReuters or S&P CapitalIQ offerings. Probably ...
356 views

### 3D orbits and inaccuracy over time

I wrote a little program to use Newton's Law of Universal Gravitation to animate 3 planets orbiting a central star, but I have run into a problem. Here is the code that I used to create the program (I ...
145 views

### How to draw some 2D curves in a 3D plot?

I want to plot several 2D curves (Sin[x] at y=0, Cos[x] at ...
132 views

### DumpSave for the forgetful

A few weeks ago I created a big matrix, and in order not to have to recreate it, I stored it using DumpSave["file.mx", variable]. Now I want to read it back in and ...
79 views

### Prandtl-Meyer function

I'm trying to solve for Mach number based on the given Prandtl-Meyer function, however I keep getting odd error. Here is my code: ...