0
votes
0answers
15 views
How to get path and file name of a pasted image?
Say in Documentation Center -> ImageData -> EXAMPLES ->
Basic Examples you find an image of a planetary body (Mars?).
Can one obtain the file source for this image wich is copied
into a Mathematica ...
0
votes
0answers
11 views
Plotting geodesics of upper half plane
I want to solve(neumerically)the geodesics of the upper half plane and plot. The results are quite known (i) st. lines parallel to y axis and (ii) semi circles centered on x-axis. Now the problem is ...
1
vote
0answers
13 views
Why changing list's head takes time?
Consider
AbsoluteTiming[Range[10^7];][[1]]
0.035000
and
AbsoluteTiming[HoldComplete @@ Range[10^7];][[1]]
...
2
votes
1answer
34 views
Longest string of special characters
I was answering a question the other day and my answer had several special characters in a row -- it was something like FindRoot[#, {2}] & /@ {f1, f2, f3} which ...
0
votes
0answers
45 views
Recursive Integration
I'd like to evaluate the following recursive integration using Mathematica
$$
\ M(T) = \int_0^T\int_0^\infty e^{-\delta s}g(x,s)dxds\ +\int_0^T e^{-\delta s}f(s)M(T-s)ds\,
$$
where $g(x,s)$ and ...
2
votes
1answer
36 views
Optimizing List Multiplications
I've got a list manipulation optimization problem. Consider a two-dimensional nxm list list1, and a three-dimensional nxmxm list, ...
0
votes
0answers
18 views
Inverse of a polynomial in a truncated polynomial ring
Let $N$ be a prime, and $q$ be a positive integer. Given a polynomial $f(x)$ in $R = \mathbb Z[x]/(x^N-1)$, I want to find another polynomial $f_q(x)$ in $R_q = \mathbb Z_q[x]/(x^N-1)$, such that
...
2
votes
1answer
32 views
Why do I have to perform a second ReplaceAll in this InterpolatingFunction?
I have an InterpolatingFunction that I'd like to plot, and I wonder why I have to perform a ReplaceAll on the following function:
...
4
votes
2answers
92 views
How to declare a 3D vector variable?
How can I do vector calculations without telling Mathematica the vector entries?
I have very many arbitrary linear combinations in $\mathbb{R}^3$ which I want to perform some general calculations on ...
3
votes
1answer
73 views
AstronomicalData and Planetary Heliocentric (x,y,z) Velocity Components
I'm trying to find data on the heliocentric velocities of planets in our solar system and was directed to Mathematica's AstronomicalData in a previous topic. ...
0
votes
0answers
82 views
Forecasting future Stock Prices II
I intend to do the following: I want to forecast future stock price under the following assumptions: The stock price is governed by the stochastic differential equation:
dS = μSdt + σSdWt
whereas ...
7
votes
0answers
81 views
How to calculate the volume of a convex hull?
Given a spatial curve represented by a parametric equation, is it possible in Mathematica 9 to calculate symbolically (or at least numerically) the volume of its convex hull?
2
votes
1answer
82 views
How does Mathematica calculate the nth prime?
When I enter Prime[2000000000000], the two-trillionth prime, Mathematica gives 61427839512211 for the answer after several ...
1
vote
0answers
64 views
Improving the plotting time of a very complicated expression
The quatity $R$ is defined by a complicated expression in terms of $a_1,a_2,\ldots,a_n$. Now each $a_i$ is a function of $x$, $a_i(x)$. I would like to know what is the most efficient way to ...
-1
votes
2answers
60 views
A simple ListPlot with different colours and a Tooltip
I know that the threads ListPlot with each point a different color and a legend bar and Extracting the coordinate of a particular point of interest from a ListPlot are somehow the answers to my ...
2
votes
1answer
42 views
how to set initial conditions when solving recursive equation with tables
I am solving a recursive expression with ParallelTable. Here is a MWE showing how I do it, and how I set the initial condition:
...
1
vote
0answers
37 views
Using anonymous functions instead of module or block. Bad idea? [duplicate]
Here is an example function which returns True if a point p is on an (open) line segment (A, B) assuming that Orientation[A, p, B] returns 0 if the three points are collinear:
...
3
votes
3answers
97 views
Inverting a Spline-Function (Bezier or BSpline)
I would like to use a Spline-Function to describe a transformation from one range of reals to another, that is I would like to have a function which maps a value $y$ on $x$ and for simplicity let us ...
8
votes
2answers
103 views
Distribute and analyze large datasets
I need to analyze very large datasets, and they obviously don't fit in a computer memory. I need to produce some statistics on these datasets, and this brings me here:
How can I make some statistical ...
5
votes
1answer
58 views
Default FontFamily for PlotLabel
This is probably a rather basic question and I presume I am simply unable to make proper use of the Options[] function: I am trying to figure out what the default ...
0
votes
1answer
28 views
Constraining solution's sign with NSolve
I am solving some equations in 4 variables, however, there are many solutions which are basically the same but changing relative signs of each other ... i.e. {x->-1,y->1} and {x->1,y->-1}.
...
1
vote
0answers
37 views
How to open hyperlink (from web-embedded CDF) in new tab
my problem is that I can't handle this.
Assumptions:
CDF is web-embedded. (created by me)
Hyperlink should open only after mouse clicking, no combinations with keyborad's keys are allowed.
...
0
votes
1answer
75 views
How can i get the solution of complicated equation?
This is the equation about zeta. NSolve[equation] could not solve this equation. (I think it is too complex to solve by NSolve.)
I want to know how can i solve this equation such a complicated ...
2
votes
1answer
58 views
“Save Graphic As…” does not include plot legends
I am creating some plots with Show but unfortunately the PlotLegends seems to be out of the bounding box when saving the graph.
...
0
votes
0answers
70 views
Finding all simple paths between two vertices in a graph
There are built-in methods to find a shortest path between two vertices in a graph, and the question on finding all shortest paths between two vertices has gathered quite a bit of attention.
A path ...
3
votes
1answer
72 views
How can I set multiple values to local variables in a Module?
Multiple assignment is supported by Set.
How can do something similar in Module expressions?
If I could do it, whould there be ...
5
votes
2answers
144 views
17
votes
1answer
106 views
What does Internal`InheritedBlock do?
What does the function Internal`InheritedBlock do? How is it different from the regular Block?
3
votes
2answers
48 views
How to apply multiple/complicated requirements for a pattern in a function input [duplicate]
In this question. I suggested that to test whether the input of a function was a matrix of numbers one could create the following test:
...
0
votes
1answer
82 views
Projection of a set of 4D points to the 3D space
Consider the following set of points in the 4D space:
...
-2
votes
0answers
61 views
How many combinations are there with a 4-digit pin? [closed]
A pin can be any number between 0000 and 9999. So I'm guessing there are 10,000 combinations.
But I also read somewhere that you calculate by doing 4*3*2*1 = 24.
Since you can re-use numbers, I ...
3
votes
3answers
65 views
Counting multiplications (complexity function)
I'm trying to count the number of times multiplication appears in an expression (for the purpose of constructing a ComplexityFunction that would help me simplify a terrible algebraic expression for ...
8
votes
6answers
208 views
Embed Code Into Image
I often export images(plots, matrix, arrays, etc..) from mathematica which I end up putting in word documents or uploading to the web.
The problem is that I often lose the original code and I am left ...
0
votes
0answers
7 views
Does Euler totient function gives exactly one value(answer) or LEAST calculated value(answer is NOT below this value)? [migrated]
I was studying RSA when came across Euler totient function. The definition states that- it gives the number of positive values less than n which are relatively prime to n.
I thought I had it, untill I ...
-1
votes
0answers
12 views
Statistics Question [migrated]
This is probably super simple to most of you on here, but I was chatted by a friend earlier with a question. It reads just like this:
...
1
vote
0answers
44 views
Is the TCPIP link type compressed?
Since I'm already piping a MathLink connection in a ssh tunnel (connect back is a pain!), I wonder if it makes sense to compress the data in the stream (ssh -C). As ...
2
votes
1answer
55 views
Explicit asterisk or @ sign in string patterns
What string pattern will match an explicit asterisk (*) or at-sign (@)? The obvious example, StringMatchQ["*", "\*"], returns ...
1
vote
2answers
82 views
Finding integral points on a surface
Suppose I have a dimension formula (for a Lie algebra representation) that is as follows:
$$
d(a,b) = {(a+1)(b+1)(a+b+2) \over 2}
$$
Now consider the surface $F(a,b,n) = 0 = d(a,b) -n$ where $n \in ...
2
votes
2answers
117 views
Mapping multiple functions
This question was part of a course on Mathematica written in 1998.
Each of the functions f1, f2, and f3 defined below has a root near
x=2. Map an anonymous function involving FindRoot[] onto ...
-1
votes
1answer
44 views
How to extract data of large function
Here I have one problem with command for I guess, but I am not sure. If I have function f[x] but not enough ram memory to save it in closed form, how to make code to compute it for chosen values. It ...
1
vote
0answers
44 views
5
votes
0answers
73 views
Every second evaluation in notebook front end is slow
I'm having a rather baffling problem that Wolfram was unable to help me diagnose, and I'm hoping one of you geniuses in residence here can figure it out. (I don't get access to the Technical Support ...
0
votes
0answers
40 views
Using Or While in Select [closed]
So I have a list of values containing both real and complex expressions. I want to pull out all of the values that have either a positive Imaginary part or a positive real part(if Im[#] = 0). I have ...
1
vote
3answers
84 views
Making a calculation with high precision
I would like to make the following calculation:
1/Sqrt[1 - (150^2 10^(-4))/(9 10^16.)] - 1
Mathematica 8 returns 0. The result is obviously not 0, but my ...
3
votes
0answers
44 views
Is it possible to import data from Google Analytics?
Using Mathematica, is it possible to pull data directly from Google Analytics? Unfortunately, GA exports messy csv files, and I was wondering if there was a direct ...
-3
votes
2answers
135 views
Forecast Future Stock Prices - Brownian Motion - Again
excuse me, I think I have here a technical problem with Mathematica
yesterday I posted the question with the title: Forecast Future Stock Prices - Brownian Motion
I am still not very experienced but ...
1
vote
0answers
43 views
Is this being simplified correctly? [closed]
I'm unsure if this is a bug or if it's a case of Mathematica not doing quite what I expect it to.
...
3
votes
1answer
62 views
String encoding issue with Pythonika
I use Mathematica and Pythonika to run Python code inside it. And I'm not quite sure what causes my issue: all unicode Python objects look like this: ...
0
votes
0answers
66 views
Fourier transform of a signal
I have problem of finding right answer for my problem.
Here is my equation:
$$E(t)=\sum_{n=1}^{\infty} c_n \sin\left(\frac{n \pi}{T}t\right)$$
What have I done:
I have a notebook asking for 3 ...
3
votes
1answer
57 views
Some _atomic elements' TreeForm looks confusing with Level in appearance
In[1]:= Level[1/2,{-1}]
Out[1]= {1/2}
TreeForm[1/2]
...
