The tag has no wiki summary.

learn more… | top users | synonyms

0
votes
0answers
36 views

Is the letter “s” special in Mathematica? [duplicate]

I'm finding that the two versions of the expression below evaluate differently: ...
0
votes
0answers
17 views

same variable name is persevered as different variables in to different places in single code

So I am writing a simple strait forward code and it seems as if Mathematica is perceiving the same variable as to different ones. The code is this: ...
0
votes
0answers
47 views

Need help with notations [duplicate]

I can't create a custom variable with notation. Where is my problem? I have a big computation and I need to convert it to LaTeX. ...
2
votes
0answers
62 views

Plotting data with four variables; two labels for one of the axes

I am having difficulty related to 3D plotting task. I have a set of data points in the following form : ...
1
vote
1answer
43 views

Printing names of indexed variables instead of values

I'd like to display only the variable (indexed variable) name (in symbol form, not in string form) instead of its value in Mathematica. Say I have a variable foo[i] ...
2
votes
2answers
50 views

Can i change AutoStyles colors for undefined variables?

I want to change from blue to red the color of the undefined variables; but only for the current Notebook
0
votes
1answer
55 views

Can I name a variable as D(1,0,+1/2)? [closed]

I am trying to use variables with names as D(0,0,0), D(1,1/2,+1/2), etc. but I don't know how to do it.
1
vote
1answer
59 views

Is it possible to assign a value where the target is itself a variable

If I have a variable x := "a". Is there a way I can use it to assign a value to a, by just referring to ...
0
votes
1answer
45 views

Change of variables—Galilean transformation

I have a function of two variables, f[x, y], and I wish to do a Galilean transformation, i.e., y = z - v t, where ...
0
votes
0answers
52 views

Calculating the rank of an abstract matrix

I'm trying to compute the rank of a 4x4 matrix with 4 parameters and 2 variables. I tried to calculate its rank under some assumptions on those conditions and I kept getting rank 4. So I did an ...
0
votes
1answer
55 views

How to specify the domain of a variable?

How can I specify for every expression the domain of a variable without using assumptions everytime i have to simplify it?
1
vote
1answer
51 views

How to make strong assumptions?

Or put in another way, how to make a variable behave as it belongs to a specific domain, even outside the use of simplify or other commands alike? For example: ...
0
votes
1answer
72 views

Variable change

If I have the following Hamiltonian: ...
1
vote
2answers
64 views

Solutions to multivariate equation

Is there any way to get Mathematica to give a set of solutions (pairs of x and y that are integers) to an equation with multiple variables? Something like: ...
0
votes
0answers
34 views

Substitute all known values in matrix [duplicate]

There is probably a very simple way of doing the following, but I cannot find it. I have a an array of symbolic variables: coefficients = Array[c, 3] I then ...
1
vote
1answer
49 views

Problem using variable loaded from TextField

I'm trying to make a simple app, which loads some data via TextFields and then does something with that, but ... ...
1
vote
1answer
62 views

How can I plot a 3D graph that shows how a histogram varies with a particular parameter?

How can I plot a 3D graph that shows how a histogram varies with a particular parameter? A simple example of this would be plotting a histogram of data described by a gaussian. The gaussian is of ...
0
votes
0answers
29 views

List of symbol names using `SymbolName` [duplicate]

With a list of variables, I want to create a table with variable names as TableHeadings. I am trying to get the list of variable names using the following code: ...
0
votes
0answers
74 views

How to assign equation solutions to variables [duplicate]

I have 12x12 Matrix with which I have to solve the equation below: ...
0
votes
0answers
9 views

Watching variables during Notebook work session [duplicate]

One feature that I have always wanted but could not find out if it was supported and that is to actively watch variables and their values while working in a Notebook session. In fact, there are two ...
1
vote
2answers
37 views

Summing over n variables [duplicate]

I am currently trying to create a function taht will sum over n variables, but I don't really know how ot implement it. It should look like this: $f[n]=\left(\frac{1}{6}\right)^n \sum _{x_1=1}^6\sum ...
0
votes
0answers
89 views

Add constraints to a variable number of parameter in Minimize

i want to use Minimize with a variable number of Parameter which works fine: ...
2
votes
1answer
86 views

Equivalent command to the Maple indets command

This carries on the discussion here and here. I had mistaken Variable[] to give you ALL variables in an expression, but apparently, it is not meant for that. ...
5
votes
1answer
125 views

Get expression type?

Is there a built in function that distinguishes between different kinds of variables? I mean something like: ...
0
votes
1answer
127 views

Explanation for coloring of variables by code editor?

I was working on some homework just now, and I realized that some of my variables have different colors, and I am not sure why. In the example below f is black, ...
0
votes
1answer
61 views

Get all variables in an expression with Variables[]

"\[Phi]" <> "1"; Variables[%] Exp["\[Phi]" <> "1"]; Variables[%] Exp[Subscript[\[Phi], 1]]; Variables[%] Say I have lots of variables used for ...
0
votes
0answers
41 views

Replacing variable names in a notebook

I am working on a code that simply imports and graphs a function. If I preset the directory I would have something that looks like this: ...
7
votes
2answers
250 views

Display variable name instead of value

Is there a way to display the variable name instead of its value? for example, I need something likevarname = 1; function[varname]; and the output is ...
1
vote
2answers
139 views

Pass the list of variables into function to change their values

I'm new to Mathematica, so I don't really know, how do what I want, and I don't even know how to google it. Doing one Mathematica task for my supervisor, I faced the following problem. I need to ...
1
vote
2answers
81 views

why the variable scope is not local when using evaluate to plot multicurve?

I noticed a surprising problem when using evaluate to plot multicurve, "evaluate" function actually consider global variable first, not the local! I can illustrate the problem using the following ...
1
vote
0answers
46 views

Settings to disable global scope

I am building a fairly large application in Mathematica, and globally scoped variables are causing issues. I would like globally scoped variables to be out-of-scope for my expressions, except by ...
0
votes
1answer
50 views

Why do For[] loop variables in different functions interfere?

I had something along the lines of: ...
0
votes
1answer
94 views

Assign values to variable names in lists

I hope somebody can help me in this (I guess) simple question: I have a list of variable names ls={w0,w1,w2} and another list of values ...
2
votes
2answers
73 views

Pattern evaluation in nested function call

I'll put the question right here, but will add some context below in case someone wonders why the heck I'm trying to do this. Why is it that I have to do two passes to get the value of the arguments ...
0
votes
2answers
645 views

How to pass a list as function argument?

I have the following function lFreqPhylo[a_, Q_, b_, p_] := Sum[Log[freqFunction[r[[p]][[i]], L[[p]][[i]], a, Q, b, {i, 1, nbranches[[p]]}]; The objects L, r ...
0
votes
1answer
31 views

How to output local variables when error message is generated without interrupting evaluation?

I am running a calculation to generate a dataset. I use several iterations to sweep over a parameter space. A few times an error message is generated (which is not the problem per se). Is it possible ...
2
votes
2answers
131 views

Using a variable for two different purposes

I want to name a bunch of tables after the OEIS entries which describe them. Is there any way to use these names for both the table name and the link at the same time? The second line uses the ...
2
votes
1answer
84 views

Strange behavior using variable in Exists

I came across a behavior that doesn't make sense to me when I tried to use Exists in Reduce. If I run commands: ...
5
votes
1answer
264 views

Variable number of nested variable-range sums

I would like to express the following nested sum in Mathematica: $$ S(m,j,N) = \sum_{k_1=m+j-1}^{N-1} f(N,k_1) \sum_{k_2=m+j-2}^{k_1-1} f(k_1,k_2) \cdots \sum_{k_m=j}^{k_{m-1}-1} f(k_{m-1},k_m) $$ ...
1
vote
2answers
180 views

Do multiple instances of Mathematica run completely independently?

Let me simplify the problem I am trying to solve so that the issue I face is highlighted. Say, I want to generate $n$ samples of a Gaussian random variable. I have a script (say ...
0
votes
1answer
182 views

Taking the time derivative of a function with more than one variable depending on t? [closed]

Yeah, I was wondering if it was possible ? I have a function which have different variables depending on time, like: $$\frac{d}{dt}mr^{2}\dot{\phi}$$ In this case both $r$, being a length, depends ...
4
votes
1answer
162 views

Why does one of my Manipulate integer variables get turned into a real?

I'm developing code for manipulating graphs. Spot the difference in the 2 Manipulates below: ...
1
vote
2answers
188 views

Using Array Elements as Function Arguments

Suppose I have an array p = {a,b,c,d} and a function f that takes a variable number of arguments. I want to evaluate ...
0
votes
0answers
42 views

Block, With, Module, can anyone help me understand the distinction? [duplicate]

I've been working heavily with Block[] for months in my research so I've read the documentation for the seemingly similar commands With[], Block[], and Module[]. Personally, I've had by far the ...
2
votes
2answers
118 views

Testing for arbitrary algebraic expression in given variable

I want to test, for example with MatchQ, if the argument of a function is an arbitrary expression in a single or several variables whose names can be assumed to be ...
0
votes
0answers
29 views

How to pass rules to packages [duplicate]

EDIT: After helpful comment from @Mr.Wizard I added the working implementation below for future reference. I wrote a module that does something with variables provided in form of a rule. It works ...
6
votes
4answers
177 views

Generate list of strings from a list of assigned variables

How do I generate a list of strings from a list of assigned variables? Eg. Convert ...
1
vote
1answer
57 views

storing rescaled images in new variables

I'm trying to assign random image files that undergo rescaling to a list of variable names. The images I'm trying to assign are the result of mapping the ImageResize function of two arguments to the ...
0
votes
0answers
180 views

Assign variable's value programmatically

Not easy to explain what I'm looking for, so please sorry if I'm not so short. Having many variables to be managed in several different combinations, I need to automate the assignment of preset ...