# All Questions

9 views

### How to measure the Speed of ball from a video or a set of pictures?

Suppose a camera and the need to measure the speed of a ball such as a tennis ball. Usually, the speed of ball is measured with Doppler effect where the pulse difference reveals the speed. Now I want ...
24 views

### How to copy a function by value?

I need to change a function symbol multiple times by assigning another symbol to it, but when I'm trying to do that the symbols overwrite each other. I'm assuming this is because the assignment is by ...
15 views

### NIntegrate - WorkingPrecision

I am trying to NIntegrate this expression. It is very close to zero, and so gives all possible types of errors. More precisely, ...
14 views

### NDSolve - sampling for result during the computation

I am using NDSolve for a Langevin dynamics problem. I want to the know long term behaviour of my system ($t>1$) but it has to be simulated with very small time steps ($dt\sim 10^-9$). An example ...
33 views

### Import Math Renderings from Wikipedia

Wikipedia uses the following mark-up language to represent (in this Example Bayes' Rule) :$P(H\mid E) = \frac{P(E\mid H) \cdot P(H)}{P(E)}$ ...
25 views

### Ordered indices of a multiple product or sum

Given a summation like $$\sum_{1 \leq i_1 < i_2 < \dotsc < i_k \leq n} f(i_1, i_2, \dotsc , i_k)$$ how can the lists of indices be enumerated? For example, if $n=4$ then the possible lists ...
19 views

### Using SetDelayed wih SQLExecute

I want to create a reusable line of code that I can send a column, table name and criteria to match using the WHERE clause. ...
32 views

### Expressing a joint distribution for use in ContourPLot

I have $$X_1=T + W$$ $$X_2=2 T + 3 W$$ where $$W \sim N(3,5) \,\text{;}\,\, T \sim N(1,2)$$ and $$P(X=X_1)=P(X=X_2)=\tfrac{1}{2}$$ which I have awkwardly expressed as ...
21 views

### What is “ (Dialog) Input [ ] := ” after evaluating a cell?

I have done a time-consuming run and calculation. After many hours ( about 7 hours!), the black color which shows that the cell is evaluating, turn into gray and a strange text appears like this : ...
67 views

### Riffle and Partition

At some point I noticed that I was using Riffle and Partition together a lot. I would do things like ...
18 views

### Prevent package from being opened in a notebook interface

I have a package which I need to deploy in a client's environment. It has proprietary code and solutions that I need to protect from prying eyes and inquisitive minds. The forum has discussed much ...
46 views

### Scope of variables within a Manipulate expression

I have a problem in defining the local variables. I have this code: ...
25 views

### Manipulate curve together with data list [on hold]

I have a function with two parameters that I want to play with by using "Manipulate[]". And a list of data that i would like to plot together with the function and see them under "Manipulate output ...
42 views

### How do I count a number of primes(say smaller than N) that does not contain 5?

Title says it all. How do I count a number of primes(say smaller than N) that does not contain 5?
31 views

### nested series expansion

I have to invert the following matrix in which the functions U[t,x,y,r] and K[t,x,y,r] and all their derivatives are "small"; ...
45 views

### Kronecker delta notation

Is there an easier way to enter KroneckerDelta[n,m] in Mathematica? When I use the notation $\delta_{n,m}$, it won't work.
36 views

### Plotting the solutions of a system of differential equations on a simplex

I want to solve and plot the solutions of the following system on the triangle simplex: x'[t] == x[t]*(2*x[t] - 2) y'[t] == y[t]*(2*x[t]) z'[t] == z[t]*(2*x[t]) ...
47 views

### Graphplot doesn't connect vertices properly [on hold]

My problem is that the following: ...
39 views

### Substituting a function in the output

I have to calculate the derivatives of the function K defined in the code: ...
41 views

### Check if n! is divisible by an arbitrary number m [on hold]

If m\<\n, then it is divisible. What happens when m>\n ? Is there an efficient method to perform this check?
49 views

### alignment of plots [on hold]

I want to align my plots like I did with Gird[]. But you cracks here are using these short forms all the time. So, is there a way to achive this result in a better ...
37 views

### Is there a way to use pause in Manipulate?

Is there a way to do any similar to Do[Print["Iteration...", j]; Pause[1], {j, 1, 6}] with Manipulate? (to show the ...
64 views

### Is there a PrimeQ whose accuracy guarantee you can adjust?

Say I have a list of a million integers each with a million digits, and I want a crude sieve to see which have a chance at being prime. Mathematica has a PrimeQ function, which appears to be slow ...
31 views

### Given two samples, how does LocationTest select its AutomaticTest?

How does LocationTest select its "AutomaticTest" when testing two samples? Background: A previous post poses a similar question ...
653 views

### Detecting patterns of black and white stones on a 2D board

I'm writing a program to play a game of Pente, and I'm struggling with the following question: What's the best way to detect patterns on a two-dimensional board? For example, in Pente a pair of ...
17 views

### square footage to non linear time [migrated]

I'm a tarp maker and I'm trying to figure out how long it takes me to move the tarp around depending on the square footage of the tarp. For instance, it takes me 2 minutes to handle a 10sqft tarp, ...
24 views

### Linear functions [on hold]

F(x)=x^2/x+3 The following rational function describes blood concentration of a certain drug taken via IV over time First A). First the horizontal or oblique asymptote, if any B). the vertical ...
36 views

### ListPlot, PlotMarker -> y value [duplicate]

at first sorry if this question is already answered. I would like to display y value as plot marker in listplot ...
31 views

### Which doesn't accept a list as the condition [on hold]

Which doesn't evaluate a list. Furthermore, if a list is included as a test condition, that condition and everything after it fails: ...
45 views

### DSolve will not apply assumption m ∈ Integers

I am trying to solve a linear second order ODE using DSolve which involves an arbitrary integer m. ...
167 views

### Extracting financial indicator data from trading chart

How can the data of the directional movement index below be extracted from this chart? It seems to be embedded in some kind of dynamic module. ...
58 views

### How can I find a root of my transcendental equation near a certain point?

What function could I use to solve this equation for x: E^(-x^2) = 1 - Cos[x] I tried Solve, ...
141 views

### StringReplace, ReplaceAll and Rule interact in a bizarre way

I have the following pair of things: ClearAll[foo, labeledFoo]; labeledFoo = {"FooBarBazQuux", foo}; This works like you'd expect: ...
59 views

### How write this Function with many arguments? [duplicate]

F[x1_,x2_,...,x99_]:=expr How to write this Function in mathematica whithout complete write it?
39 views

### Graphing a piecewise function with very different time scales? [on hold]

I'm trying to graph a piecewise function, but the issue is that in one part of the plot, for example, there is extremely rapid growth within a tiny fraction of a second. Then, in another part of the ...
83 views

### Solve a system of M equations without specifying M

This post has been edited heavily in response to the comments: my initial question was very confusing. I am trying to write my game-theoretic model in Wolfram Language. There is only one remaining ...
56 views

### How do I upload a graph as an adjacency list and find the betweenness centrality?

I have an undirected simple graph in a .txt file formatted as an adjacency list like this: 100 200 200 300 300 400 500 600 700 800 900 ... Every number is a node ...
43 views

### Append subscript to variable name [duplicate]

I'm importing equations from Word document and transforming them into input form. But subscripts look ugly. Is is possible to programmatically append subscript to variable name? e.g. ...
62 views

### Traces of products of Pauli matrices

Given a matrix $M$ of shape $2^L*2^L$, I would like to compute all the traces $\text{Tr}( M.(\sigma^{n_1}\otimes\sigma^{n_2}\otimes\ldots\otimes\sigma^{n_L}))$ for $n_1=1...4$, $n_2=1...4$, ..., ...
21 views

### Understanding the parameters required for Regression Analysis [on hold]

I have some data I would like to perform some regression analysis on so that I can create a formula to predict y given x. I ...
23 views

### Series expansion hangs on second evaluation [on hold]

I use this code to get the binomial expansion of $(1+x)^\frac{-1}{2}$ Series[(1 + x)^(-1/2), {x, 0, 30}] For the first time I excute the code it takes 0.036000 ...
52 views

### How can I insert the current date in a text cell? [on hold]

Ok I must be missing something. I have a section with the "last updated date" in a text cell, I'd like it to autoupdate. Is there a "insert current date" command hidden away in some menu?
62 views

### Optimizing evaluation time

I have the following code and it takes like foreeeeever to evaulate: ...
51 views

### Visualizing Dynamic Time Warping [duplicate]

I need combine 3 graphics into something like this Any ideas?
100 views

### How can i integrate over a set of data

i need to integrate over my data, which is denoted as {q, I},here I is the Intensity i need to obtain the form of the following integration( its not a numeric integration, because it contain x, next ...
22 views

### Minimizing roots of a transcendental equations [duplicate]

I'm trying to use the solution of FindRoot with parameters for further calculations. Annoyingly enough it always gives me trouble with replacing the parameters. As an example I'm attaching a simple ...
53 views

### Text with date, how to convert?

I use this script to recognise a date in a textfile and write the result in another file. ...
24 views

### partitioning up the time series data set in order to remove up the anomaly [on hold]

My problem is to detect anomaly in time series based data, for that i need to partition up the data according to their minima and maxima. For this i need to get the matlab code to find the maxima and ...