All Questions

0
votes
0answers
7 views

Curve fitting of a list

I have list obtained using an integrals. I want to obtain an analytical formula that fits my list using curve fitting. Please suggest a simple analytical structure that fits my curve. ...
0
votes
0answers
6 views

Histogram from a list of matrices

I have a list of around 100 matrices, that looks like this ...
0
votes
1answer
21 views

Using RegionPlot3D to make a cone under restrictions

I have to plot a cone that satisfies this statement: Use the RegionPlot3D command to draw a picture of a cone with its point at the origin. The other end of the cone is a circle with radius 5 ...
0
votes
0answers
8 views

Grid lines extending too far

The grid lines in the following plot extend beyond the data and, in particular, into the numbers along the axis. ...
0
votes
1answer
32 views

Wrong Definite Integral result

When I calculate the definite integrate of (a+bt)*cos(nt). Integrate[(a + b t) Cos[n t], {t, t1, t2}] MMA gives a correct answer: ...
9
votes
2answers
144 views

How to wrap a plot around a circle?

Consider the code a = Table[BesselJ[i, x], {i, 0, 3}] Plot[a, {x, 0, 20}, Axes -> False] producing I'd like to transform the plot into a circle. In other ...
0
votes
0answers
12 views

How to automatically Import, Name and Export multiple images?

Sorry for the very basic question but I'm really new to Mathematica. I have a directory(myDataDir) full of images (myImage1.tif, myImage2.tif...) I have a piece of code (let's call it ...
0
votes
0answers
94 views

Suggestion Bar Gone in Mathematica 9

I was using Mathematica 9 for some time without any problem. And suddenly the suggestion bar dissapear, and i used it a lot. The option "Show suggestion bar after last output" is checked. Also I tried ...
2
votes
6answers
127 views

Command to take the first elements of a list that match a pattern

I want to find the number of elements in a list in a row that match a certain pattern. So for this list {1,1,1,1,0,0,0,1,1,1} It should return "4" because there ...
4
votes
3answers
89 views

How to separate factors by dependent variables (arguments)?

How can I separate factors in an expression by their dependent variables? For example: expr = b * c[2] * a[x] * 2 * x^2 * g[x,y] * z[r] * D[q[x], {x, 4}]; I ...
2
votes
3answers
78 views

Partitioning time series

I have a time series dataset I'm trying to plot by Year: ...
26
votes
5answers
6k views

How to use Mathematica functions in Python programs?

I'd like to know how can I call Mathematica functions from Python. I appreciate a example, for example, using the Mathematica function Prime. I had search about MathLink but how to use it in Python ...
0
votes
0answers
64 views

Can not understand the code to plot Fourier Series approximation of the line

I'm reading the CDF file from Making Formulas… for Everything in wolframalpha blog. When I step into In[9] and In[10], I'm fully confused. Who can tell me what does the two functions mean? The ...
0
votes
0answers
17 views

Using real numbers gives suspicious result

In the code below when I use a real number for number 4 in the exponent in the irf function, it returns wrong result. ...
1
vote
0answers
29 views

Open Mathematica in text editor displaying just the code

I need to translate some code to another language and I don't have a working copy of mathematica. All I need it to do is display the code exactly as it would in mathematica, without any of the fancy ...
5
votes
3answers
105 views

How do I display the parameter value in animate, similar to how it's done in manipulate?

When I use manipulate, there is a 'plus sign' in the top right that, if I click on, shows my parameter value. I used animate, because other posts suggested that it solved other issues I had, but now ...
0
votes
1answer
101 views

Replacing powers of $n$-th partial sums in the output of a function with $S[i]$ for $i = 1,\ldots,n$

I've written some simple code that, for various $N \geq 1$ and $k = 1,\ldots,N+1$ computes the $n$-th derivative of $\log S_N$ where $S_N(z) = \sum_{k=0}^N \frac{1}{k!}z^k$ as follows: ...
1
vote
0answers
34 views

Implementing normalization/rescalement from a Tutorial

I'm trying to implement a rescale/normalization as is described in here by mathematical expressions in page 10, and code in the top part of page 16. The notebook is also available here. The objective ...
1
vote
3answers
61 views

Randomly changing matrix entries

1.Write a block of code that generates a 4x4 matrix with randomized real number entries each between 0 & 1, then selects 3 matrix entries at random, and finally replaces these 3 entries with a ...
7
votes
1answer
782 views

Hardware Performance Metrics for Mathematica

Dear Mathematica users I am looking into buying a new computer and Mathematica is one of the main applications I run. To help me assess the overwhelming welter of choice out there: I'd like to know ...
-1
votes
0answers
29 views

How to replace colours in an image from Wolfram Alpha [on hold]

I recently saw this post on the Wolfram Blog. I have tried doing the exact same thing on the blog but I'm not getting the same results. I'm getting this image: Instead of this: I'm also ...
3
votes
3answers
115 views

How to do algebra on unsolved integrals?

I am working with functions calculated from a set of general basis functions. ...
1
vote
1answer
55 views

How to form a variable from matrix elements

I have matrix with n rows and 2 columns, say m = {{x11, y12}, {x21, y22}, ..., {xn1, yn2}. Now, I want to form three new variables for example: ...
2
votes
1answer
46 views

Remove redundant parameters from equation

I have random expressions like (b1 x + b2 x)/(b3 + b4/b5 x) + Sin[b6 x] where $x$ is a variable and {b1, ..., b6} are parameters to be fitted. This expression is ...
0
votes
0answers
35 views

Handling Accuracy and Simplifying

I have the following problem. I have a system of non-linear equations that I log-linearize around a certain point, let's call it point A, using a function that I ...
6
votes
2answers
105 views

Connecting to LeapMotion

Thanks to those who helped me with my previous question. I will help others too where I can. In the meantime I have a general question whether anyone has had success connecting Mathematica to the ...
6
votes
1answer
203 views

Is there an easy way to use Matteo Niccoli's perceptual color maps for 2D plots in Mathematica?

I have been using the ubiquitous Jet color palette for 2D plots for some time now, and don't really care for it. Then I came across the series of blog posts, The rainbow is dead...long live the ...
-1
votes
0answers
27 views

Proof that $(1+\epsilon)^n = O(n\epsilon)$ [on hold]

How to prove that $(1+\epsilon)^n = O(n\epsilon)$ ? So far I proved the following: By the binomial, $(1+\epsilon)^n > n\epsilon$ Also $\epsilon^n$ = 0 when n-> infinity.
0
votes
0answers
58 views

Problem in Plot at start [duplicate]

The derivative can be used to calculate roots. However the same function cannot be plotted.The error is at start point of domain: ...
0
votes
2answers
62 views

How to solve ArcSinh equation for many differents parameters?

I am totally stuck trying to solve the equation below (1/2) x Sqrt[1 + 4 a^2 x^2] + ArcSinh[2 a x]/(4 a) == d Where a and ...
4
votes
1answer
47 views

Functional defined Ticks of LogLinearPlot does not work

version 10 $Version "10.0 for Microsoft Windows (64-bit) (June 29, 2014)" Consider three cases in LogLinearPlot's ...
33
votes
5answers
1k views

How to abort on any message generated?

Mathematica is a bit unusual as a programming language because it never stops on messages, regardless of whether the message is an error, a warning or just an informative message. It simply prints the ...
2
votes
1answer
28 views

Mapping also for one element (or telling it how to do so if head got changed)

Some code generates a polynomial, and has the form: expr = Plus[a[i],b[i],c[i],d[i]] I need to apply f to each term. To do ...
1
vote
1answer
54 views

handling division by zeros and line equations

today I was writing a code which takes some line equation and a circle equation,finds intersection points that are on $II$ and $III$ quadrants,draw a tangent line to circle from that point and then ...
1
vote
1answer
55 views

Changing the Ticks in LogLinearPlot for representation pH values

I need to change the ticks in the xaxis for representation pH values, but the ticks are not dispersed along the range of xaxis. Another question: why the vertical line defined with Epilog is not ...
0
votes
0answers
37 views

Is There a Reliable Way to Solve the Following Non-linear PDE Using Mathematica? [on hold]

I'm trying to solve the following non-linear PDE using Mathematica. Indeed I should write my own codes, but I didn't do it for two reasons: 1. there seems not to be any reliable way to "discretize" a ...
0
votes
0answers
44 views

Using FindFit to return a list of possible best fits

Can I use some variant of FindFit that will return a list of the best fit and some worse fits, not just the best fit? This is for a function where the residual function can have several local ...
0
votes
1answer
31 views

Why can't I import a file in the init.m file?

I would like to have some data read in every time the kernel starts, but it doesn't seem to work. Say I have a CSV file I want to have read in, for example I use: ...
3
votes
2answers
80 views

ContextPath and autocompletion with subpackages

I'm developing a larger package which includes several subpackages. My problem is, that I can't introduce the symbols in the subpackages to the autocompletion by loading the main package, but by ...
0
votes
0answers
40 views

Empty Graph for Absolute Function

I wanted to plot the following equation: Plot[((x/7)^2 Sqrt[(Abs[Abs[x] - 3]/(Abs[x] - 3))] + (y/ 3)^2 Sqrt[(Abs[y + 3 Sqrt[33]/7])/(y + 3 Sqrt[33]/7)] - 1) (Abs[x/2] - ((3 ...
0
votes
0answers
57 views

Mathematica ERROR [on hold]

I would like to know what your opinion is about this paper and the discovered errors: http://www.ams.org/notices/201410/rnoti-p1249.pdf I also like mathematica, but nevertheless a statement of ...
1
vote
1answer
25 views

problem on returning value of function as a list using if

today i was writing a function for my project using mathematica that gives a line equation in form of $y=mx+b$ and a circle equation in form of $x^2+y^2=r^2$ and finds the intersection point which is ...
9
votes
4answers
250 views

Rotated Rectangles

I would like to produce an image similar to the upper half of this graphics by Victor Vasarely. All I could produce so far is this dilettante image: ...
2
votes
1answer
35 views

Is there a simple function identify the sign of an expression given constraints

I'm looking to find a simple function that can identify the sign of an expression given a set of constraints. I have looked around and do see that there is a few threads on this but I'm not sure I ...
0
votes
0answers
28 views

Series expansion of InterpolatingFunction obtained from NDSolve

I am trying to obtain a series expansion of the numerical solution of a differential equation. I encounter difficulties going beyond first-order expansions which I believe might be due to my inability ...
3
votes
3answers
235 views

How can we plot the complex roots of an equation?

If we'd like to display the $n$ roots of a polynomial on the complex plane as points, how can we do this? For example, if we have the equation $x^3 + x^2 + x + 1$, how can we plot the 3 roots as ...
0
votes
1answer
39 views

Why don't these assumptions result in further simplification?

I'm trying to simplify an expression, which has a factor of $\lambda(\lambda-1)$, where $\lambda$ may be either $1$, or $0$. So I try: ...
23
votes
7answers
6k views

Even Fibonacci numbers

Today, I found the Euler Project. Problem #2 is Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be: ...
13
votes
0answers
112 views

DumpsterDoofus's captivating generative art

How can I render these beautiful images that DumpsterDoofus posted?
22
votes
6answers
3k views

Fixing quirky typesetting in plot labels

Consider this example plot. Plot[ 1-Exp[-x], {x,0,3}, AxesLabel->{"thickness (μm)","power density (W/m^2)"} ] Let us hold the typographical quality of ...

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