9
votes
2answers
248 views

ScheduledTask with scoped variables. Working with timed evaluation

I guess I have to try harder and focus more but timed evaluation always frustrates me. I will show the issue on simple example of delayed trigger. ...
4
votes
2answers
128 views

Gamma function computation efficiency?

I wonder what kind of algorithm is used to compute the values for the gamma function. Specifically, I am interested in how the computational load increases when the complexity of the input grows. So, ...
2
votes
1answer
141 views

Reproducing a Plot done with WolframAlpha [duplicate]

I have problem to draw in Mathematica a plot like this: Plot[{Sum[a^10*(-1)^(x-a), {a, 1, x}]}, {x, 1, 10}] The problem is that on the plot there is no graph. As ...
3
votes
2answers
190 views

Using high RasterSize or ImageResolution changes contour pattern

I found that the detailed contour pattern will be altered if we Rasterize the original graphics using high RasterSize or ...
9
votes
3answers
230 views
0
votes
3answers
323 views

Solving a differential equation with mixed conditions using DSolve

I want to solve a differential equation $$ \frac{d}{dx}\left(k_0 \left(\frac{T(x)}{T_0}\right)^n \frac{dT(x)}{dx}\right)=0,$$ with boundary conditions: $T(l)=T_0$, $\;T'(0)=-\frac{q_0}{k_0 ...
6
votes
1answer
72 views

Infix strange behaviour

Maybe this is a bug or maybe Infix acts differently than the other functions. The fact is that both: TreeForm[Infix[f[x, a]]] and ...
0
votes
1answer
110 views

How to create 2k sized vector in k sized loop

I want to solve a system of simple differential equations. At some point I need to solve non-linear system of algebraic equations with Newton method. I would like to efficiently create a right hand ...
6
votes
2answers
194 views

how recover lost data of coordinates from contourplot of mention data?

I have made Contour Plot for a lot of data, like this ...
0
votes
2answers
88 views

Export all open notebooks and change font size

Is there a simple way to export all open notebooks to pdfs? Also, when I export notebooks the font looks too big / the margins are too big. Can I change these settings when exporting?
1
vote
1answer
301 views

Export data of a 3D histogram

I want to export the data of a three dimensional histogram in the format # x y z with a blank line between different lines, so that one can plot the ...
0
votes
0answers
61 views

How to solve initial value problem using Runge-Kutta method? [duplicate]

How to solve the following initial value problem using Runge-Kutta method u''[x] + (2/x) u'[x] + E^(u[x]) == 0, u[0] == 0, u'[0] == 0
8
votes
1answer
67 views

How to introduce custom hot keys for the styles of cells?

In the JournalArticle StyleSheet there are useful hot keys Alt+6 for a DisplayFormulaNumbered and Alt+5 for the DisplayFormula. Such hot keys, however, are not present in the Default StyleSheet. Even ...
1
vote
2answers
112 views

How to return matching sublists or empty list

How to return matching sublists or empty list m1 = {{1, 0.5}, {2, 0.4}, {3, 0.1}}; m2 = {{1, 0.5}, {0, 0.4}, {0, 0.1}}; Commonest[Join[m1, m2]] out: ...
3
votes
0answers
114 views

Where can I find the Distributions Palette?

I was watching the "Statistics: Modeling with Statistical Distribution" Training Course http://www.wolfram.com/training/videos/DAT016/ and in one of the slides, the following image showed up. Does ...
1
vote
1answer
191 views

Interpolation of a table with 4 parameters

I have a huge data file which I need to do some analysis on it. The file is built in this way that for each 4 variables, there is a value of the function: ...
10
votes
2answers
2k views

Finding fourier transform of data and hence frequencies

I looked at all the other questions related to mine before posting this, and they didn't solve my problem. I have a large data set which can be downloaded from here. I'm using the following code to ...
11
votes
3answers
197 views

How to collect expressions from cells created by Print?

I have a notebook where evaluation of a certain cell produced hundreds of adjacent output cells using Print. I need to create a list containing all expressions from ...
2
votes
2answers
170 views

Organise data in table

I have a large amount of data available (in excel), which is not very organised. I can do this by copy paste, but I am trying to do this using mathematica. Hopefully someone can help me. I imported ...
2
votes
2answers
224 views

Check if integer has even number of digits

I want to check if a number has an even or odd number of digits. 10 would be even because it has 2 digits 300 would be odd ...
0
votes
0answers
56 views

How to make this particular replacement involving exp

I apologize if similar questions have already been asked, but I have some difficulties with replacements in Mathematica and I would like to make a substitution like ...
0
votes
0answers
315 views

Error when trying to run Mathematica 9 on Ubuntu 12.04 from the command line

When I type : mathematica or math on terminal, generates following error: ...
9
votes
2answers
219 views

Orderless pattern matching of rule lists

I am looking for a compact way to specify a pattern to match a rule list with MatchQ that allows for enumerating the rules in the rule list in an arbitrary order. ...
4
votes
0answers
438 views

What exactly is “ParameterErrors” of NonlinearModelFit?

I am trying to get what I call a "$\chi^2$ fit". This means taking a function $f(x,p)$ of the variable $x$ with a parameter $p$ and finding the value of $p$ that minimizes the "distance" from a data ...
1
vote
1answer
48 views

Financial number format

How can I change this function: nFormat=NumberForm[#,{\[Infinity],2},NumberPoint->",",NumberSeparator->".",DigitBlock->3,ExponentStep->10]&; So ...
3
votes
2answers
130 views

How to make the GroupOpeners visible in the SlideShow regime?

I am preparing a presentation on Mathematica and realized that though I made the GroupOpeners visible in the working regime (through the OptionInspector), they are invisible in the regime of the ...
0
votes
0answers
56 views

Importing and running a notebook [duplicate]

I have a very long .nb file. I want to subdivide the different sections into separate notebooks, then call them in a common nb ...
0
votes
2answers
202 views

How to solve this FindFit::nrlnum:

the following code show error message FindFit::nrlnum: "The function value {6.71759 -9.36268*10^-8\ I,6.51797 -8.42641*10^-8\ I,6.31789 -7.49014*10^-8\ I,6.1179 -6.55387*10^-8\ I,5.91794 ...
9
votes
1answer
232 views

Reducing mesh details while exporting to vector format SVG

I am trying to export a simple cuboid into .SVG format. In the output file, the cuboid is finely meshed, which increases the file size. How to remove this detailed mesh? ...
1
vote
1answer
157 views

Finding Minimum of a list after interpolation

I have a set of lists called Er[l], where l is from 1 to 13. I want to find the minimum point in the plot in these lists after interpolation by spline method. I need the values and the points on the ...
13
votes
4answers
565 views

Can (compiled) matrix permanent evaluation be further sped-up?

Update II  Sample code for simulating boson-sampling experiments has been added (as an answer). This code exploits new Mathematica capabilities relating to both empirical and smooth ...
4
votes
3answers
339 views

How to change the color of a button while it is pressed

I want to change the color of a button while it is pressed, pause for a short time and then change the color back to the original color. I can't seem to figure out how to do this (tried various forms ...
-2
votes
1answer
84 views

Using Product for different variables

when using product in mathematica the initial and maximum value of the product will be the variable itself that will be maupulated. what I need is to make these initial and maximum of the product as ...
0
votes
1answer
235 views

updating code from 5.0 to 9.0

I am updating a code from a 5.0 version to a 9.0 version. I am speaking about "Advanced visual quantum mechanics". There is a package with this code: ` ...
8
votes
3answers
243 views

Pulling constants out of integrations [duplicate]

The following is the code and output of a Mathematica command How do I get Mathematica to remove $g(y)$ outside the integral?
0
votes
0answers
161 views

RowReduce : Record of all the row operations for RREF

I read "for what right-hand sides $b=(a,b,c)$ does $Ax=b$ have a solution", but that question pertains to solving for the unknown vector. I'd like a record of all of the row operations required to put ...
0
votes
0answers
73 views

Hypergeom to Bessel

Is there any way to get Bessel function equivalent to a Hypergeom function. Would it be possible in general ? From maple integration (As discussed in Answer ID 37931), the result of a symbolic ...
0
votes
1answer
80 views

Having Trouble Solving this System of ODEs

I am having trouble finding any solution to this ODE: ...
5
votes
3answers
341 views

How to make a control array of buttons or togglers?

An array of buttons From time to time I wish I had a control array of the sort native to Visual Basic. A control array of buttons would be a table of buttons in which each button "knows" its ...
1
vote
2answers
140 views

Why does using ReplaceAll twice produce a different result?

Why does this: Solve[a x^4 + b x^3 + c x^2 + d x + e == 0, x] /. {2 c^3 - 9 b c d + 27 a d^2 + 27 b^2 e - 72 a c e -> F} produce a different result from ...
2
votes
1answer
306 views

Integrate message: can't prove Integration limits are real

I'm working on solving differential equations through Fourier series, I made a function to help me calculate the coefficients that looks like this: ...
11
votes
1answer
351 views

How do I evaluate Mathematica expressions and insert them in a LaTeX file?

I want to make use of Mathematica as the backend to solve some computations used in my LaTeX input file. As I have no knowledge to make it in Mathematica, I used Maxima as explained in the following ...
3
votes
2answers
600 views

How can I scale the y axis?

I have a file I import and read into a table of $2 \times n$. I can plot this data using the following code: ...
1
vote
3answers
215 views

Code hanging inside a For loop

I'm pretty new to Mathematica (and functional programming in general). I'm working on some code to find winners (maximal values) in a list. The code I have that is hanging is this line. ...
0
votes
1answer
197 views

How to improve the performance of this code

I have implemented a code in Mathematica 9 to simulate a scattering problem, and I got really disappointed about its performance when compared to Matlab. Since I am a newbie in Mathematica, would ...
6
votes
1answer
79 views

Is it possible to find a function from first few terms in the expansion

Is it possible to find a function if first few terms of the expansion is known. For example if I have this series $f(x)=\frac{k^3 x^2}{6}-\frac{k^5 x^4}{120}+\frac{k^7 x^6}{5040}-\frac{k^9 ...
1
vote
0answers
50 views

Arrowed circular arc [duplicate]

I would like to draw a circular arc with an arrow head, let's say following the syntax for Circle[]: ArcArrow[{x,y},r,{q1,q2}] ...
1
vote
1answer
76 views

check if the expression is a equation

I need to check if the expression is a correct equation with only 1 variable x and without functions, that are not build into Mathematica. For example Sin[x]==0 ...
10
votes
3answers
388 views

Reduce can't reduce an equation without appropriate assumptions

When there are three unknowns (x, y, z), Mathematica can solve it: ...
4
votes
1answer
873 views

How to set the working precision globally? $MinPrecision does not work

I want to increase the precision globally to 50 at least, but $MinPrecision does not work. ...

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