8
votes
2answers
584 views

Why Fourier doesn't show me the peaks?

I'm trying to identify the frequencies in my time history samples, and I can see a frequency in the time history, but can't see it in its Fourier transform. Here it is : the sample data: ...
3
votes
1answer
293 views

ParametricNDSolve and Constraint satisfaction problem

I am trying to find the values of two parameters that allow for a specific result of my differential equations, under different initial conditions. Given a system of equations: ...
2
votes
1answer
202 views

Writing CSV or alternative

I've tried to export a list to a CSV file. I shut it down after about 20 minutes of processing. The list has 261,000 rows and 30 columns. I finally exported it to a txt file and its size was 111 ...
3
votes
1answer
234 views

Importing a ragged array while ignoring rows that start with “#” [duplicate]

I am new to Mathematica, and I find that there may be a lot of ways of doing this. I was wondering which one might be the most general. I am importing data from ...
0
votes
1answer
778 views

Can graph interpolating function, but not use it. Any thoughts?

When solving a system of differential equations numerically, I get two interpolating functions. I can graph both of these, but when I try to evaluate either of the functions at a point, it just spits ...
3
votes
0answers
181 views

How to batch run Mathematica code from Python?

I have this notebook: ...
1
vote
2answers
188 views

Symbolic integral with distributions

Why is Integrate[ HeavisideTheta[1 - x^2] DiracDelta[1 - x^2] , {x, 0, 1} ] (*0*) It should be HeavisideTheta[0]?
3
votes
2answers
154 views

How to produce multiple plots from a multiple data sets

I have a number of lists and want to plot all of them vs each other. E.g.: l={ {a,2,5,4,6}, {b,4,6,6,2}, {c,2,8,3,5}, {d,1,5,2,5} } Now I want multiple plots ...
9
votes
1answer
1k views

Measure length and diameter of objects in an image

I am new to Mathematica, and I am trying measure length and diameter of rectangular objects in an image. I wanted to fit rectangles in the objects, and then get the values. Can I do that with ...
8
votes
1answer
399 views

How to do computations simultaneously in multiple notebooks? [duplicate]

I have a Mathematica script which takes a few hours to run. I want to be able to open another notebook while it's running and do some other computations. I have enough many cores on my computer for ...
4
votes
2answers
418 views

Why doesn't Mathematica divide out the Kelvins?

I thought I understood Mathematica V9 units. However, I can't get these numbers to plot, or even to come out to a nice clean unit of mass (say grams). The Kelvin's ...
6
votes
0answers
86 views

Does one need to be careful about loading multiple (many) contexts or packages in the same session?

I have a number of large pieces of precomputed data which I am considering putting into individual packages in order to load them (via DeclarePackage) and unload ...
5
votes
1answer
147 views

Remove Removed From Output

How might I remove Removed[..] symbols from the output of an expression? For example Clear[b]; b := Sin[a + a]; Remove[a]; b ...
0
votes
2answers
269 views

How Do I Upgrade a Show to a Manipulate?

I'm trying to ilustrate the difficulties in assigning bins to a data set and then running a comparison of the bins against a binomial distribution for all values- n, p. The code I have so far is ...
22
votes
2answers
2k views

Export to Google Spreadsheet with OAuthAuthentication

Context I'm trying to setup a connection between Mathematica and Google Docs. Specifically, I would like to be able to export data to a Google Spreadsheet (Note: if the spreadsheet is public it's ...
1
vote
1answer
100 views

Increase Size of InputForm in Manipulate

I would like to set a variable equal to a copy n' pasted list, all within the Manipulate[] environment: Manipulate[list,{list,0}] I would like to view and edit ...
0
votes
2answers
228 views

Interpolating a ParametricFunction

Original domain of my independent variable t is 0 to 10 nanometers, but in Mathematica (as in most numerical software), it's good idea to solve differential ...
4
votes
3answers
275 views

make specific cluster

I have set of coordinates. I want to make clusters in which every point is within 1.5 distance unit of it's neighbor. ex of point coordinates: ...
0
votes
1answer
154 views

Understanding output of multivariable integration

I'm new to Mathematica and I'm trying to integrate this function: ...
8
votes
1answer
190 views

After modifying expression, new result doesn't replace old one

After I modify and re-evaluate an expression, the new result doesn't replace the old one. Rather, what happens is that the old result gets pushed down and Mathematica displays the current result at ...
4
votes
2answers
198 views

Using two color functions in a MatrixPlot

I'm trying to use two color functions within one MatrixPlot in Mathematica. Is it possible to do this? For example, using a very simple matrix: ...
6
votes
2answers
400 views

Sierpinski carpet with GraphData

Is this graph in the list among the so-called "standard" structures used in GraphData? However, I have not found, yet, anything like "Carpet" or "Sponge" in the ...
11
votes
4answers
200 views

Constraint syntax compaction

Is there a more compact way to represent these constraints: NMaximize[{a+b+c,...
4
votes
2answers
642 views

Mathematica not plotting whole logarithmic function

I am trying to use the following input Plot[Log[E,x+1],{x,-50,50},PlotRange->50] however the output is: How can I adjust it so the line goes down to ...
2
votes
3answers
145 views

Accessing temporary value of a Nest evaluation

The function Nest[] must store the temporary values in the memory somewhere (those values that would form the entries of the list which is returned by the ...
1
vote
3answers
307 views

Creating overlapped block matrices

I'm doing an FEM assignment using Mathematica. (EK1 = {{a11, a12}, {a21, a22}}) // MatrixForm (EK2 = {{b22, b23}, {b32, b33}}) // MatrixForm I don't know how ...
3
votes
1answer
624 views

Why this numerical integration takes so long?

Let me explain the problem. I am trying to integrate a one dimensional integral: $$\int {g\left( {{k_x}},parameter1,parameter2,...\right)d{\mkern 1mu} {k_x}} $$ for the sake of clarity, I will give ...
42
votes
1answer
1k views

How can I manipulate TemporalData?

Version 9 introduced TemporalData but, truth be told, the documentation doesn't suggest that one can do much with it. Many of us have probably assumed we'd be ...
0
votes
2answers
216 views

Solving Within InverseCDF

I have the following input data: Remove["Global`*"] x = 5/30 // N; y = 0.8; μ = 0.2; T = 5; ρ = 0.8; σ (*to be determined*) And this is the given equation: ...
0
votes
1answer
298 views

FindFit: why do I get negative value as result?

I am trying fo fit a model to data using FindFit. ...
0
votes
0answers
543 views

Metric Parameters such as Pratt Figure of Merit (Pratt-FOM) for Edge Detection

I have developed a new algorithm in Mathematica v9.0 for the Edge Detection and want to compare it with the existing Roberts, Sobel, Prewitt etc, operators in the presence of Noise. I have evaluated ...
7
votes
3answers
2k views

Simulate MATLAB's meshgrid function

Here is MATLAB's meshgrid. I came up with these implementations in Mathematica: ...
1
vote
1answer
469 views

How to compute the Multifractal Spectrum of a Financial Series with WTMM

I would like to know if someone knows how to compute the Multifractal Spectrum of a Financial Time Series (Currency) througth the Wavelet Transformation Modulus Maxima (WTMM). I would highly ...
5
votes
2answers
233 views

Automate mouse clicks with Mathematica

I need to automate mouse clicks with Mathematica. However, a similiar question was closed on this forum, without any answer. Consider the following steps: ...
1
vote
0answers
383 views

NDSolve for a large system of coupled (complex valued) ODEs

The system under consideration here is a generalization of the one I discussed in this problem. Qualitatively, I am trying to solve a system of coupled nonlinear (up to order 4 in the dep variables) ...
1
vote
2answers
314 views

How do I create matrices with arbitrary list restrictions?

I want to randomly generate a square matrix of dimension n with entries in the list StartingEntries, and also satisfying that for any such matrix M, the matrix Inverse[IdentityMatrix[n] - M] has ...
6
votes
1answer
268 views

Programmatic generation of enhanced (Enterprise) CDF

How does one PROGRAMATICALLY generate enhanced CDFs under an Enterprise license? Undocumented options to CDFDeploy[] perhaps?. Wizard works fine for me, but attempts to do this programatically (from ...
1
vote
2answers
437 views

Draw the image of a complex region

I'm working on a complex question that asks that I determine a function that maps the complement of the region $D=\{z:|z+1|\le 1\}\cup\{z: |z-1|\le 1\}$ onto the upper half plane. That is, $f$ must ...
8
votes
3answers
202 views

Preserve information in flattening a nested list

I have a series of lists in the form below: list={ {1,1} , {2,2}, {3,{3,1},{3,2},{31,{31,1},{32,2}}} } Its a nested list which the dimension is changing case to ...
2
votes
2answers
195 views

Time differences between code using user-defined probability distribution and code using built-in distribution

Why is the reponse time of of kernel significantly different when I use the first code rather than the second? Shouldn it not be the same? Is there any way that the response time can be made smaller ...
0
votes
1answer
81 views

Scope of expression in a user-defined function

I have the following code: fbasic = A + R + Z*Z *Z*Z; f[A_, Z_, R_] := fbasic + R; f[0, 2, 3] The answer I am getting is ...
9
votes
1answer
97 views

IntegerDigits has Listable attributes, but not fast

See this example, a function has Listable attributes often more efficient than Map,but why is this one is an exception? ...
4
votes
4answers
276 views

Elegant Matrix Combinations

Suppose you have a matrix (mxn), simplified for illustration m= {{a, b, c}, {d, e, f}} And a set of combinations (simplified for illustration purposes but can ...
0
votes
1answer
214 views

How to compute values only if input fields are filled?

In the following code how can I keep the DynamicModule from computing values if the input values are not all filled? If I don't specify default values it will show the code used to compute the values ...
3
votes
1answer
61 views

Button ImageSize x-dimension ignored

How can a small square button be created with ImageSize -> {20,20}? The x-dimension won't go below about 70. (Using version 9.0.1 on OS X.) ...
6
votes
1answer
347 views

Changing a wave simulation

I want to adjust some code that I found on this Wolfram Demonstration: http://demonstrations.wolfram.com/WaterRipplesPassingThroughASlit/ Basically it shows a wave passing through a single slit. I ...
0
votes
2answers
178 views

Compute percentages in a list

I have a data file which contains thousands of lines and each line has eight elements. Here is a small sample of the data file ...
-2
votes
2answers
243 views

Mathematica not assigning variable correctly

So I have been fiddling with this the last hour and I just can't get it to work. I have 3 matrices of the same size which contain nothing but 0's in a list, I also have 3 matrices of the same size ...
18
votes
6answers
1k views

Looking for a way to insert multiple elements into multiple positions simultaneously in a list

I would like to take the following data: insertvalues = {r, x}; insertpositions = {{1}, {5}}; origlist = {a, b, c, d, e, f, g}; and generate output that looks ...
0
votes
1answer
499 views

Reassign Functions for Graphic Representation [closed]

How might I construct a function of the form Rep[defs,code], graphic[code] and display[code] ...

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