-1
votes
1answer
232 views
2
votes
1answer
369 views

Row echelon form question

I am wondering if there is a Mathematica command that will put a matrix in row echelon form. That is, put $$ \begin{bmatrix} 1 & 2 & 3\\ 2 & 3 & 4\\ -1 & 0 & 2 \end{bmatrix} $$...
1
vote
0answers
77 views

How to simplify an expression with a radical sign nesting in a radical sign

Is there a function can simplify an expression with a radical sign nesting in a radical sign in Mathematica? I use V9. RatDenmon is a function that can ...
1
vote
2answers
126 views

Random walk using Module [closed]

I want to create a random walk using Module. The walk start at {0, 0}. At every step, x ...
0
votes
1answer
38 views

Getting nicer values for eigensystems [closed]

I want to find the eigensystem of the matrix {{0.9, 0.5}, {0.1, 0.5}}. I tried Eigensystem[{{0.9, 0.5}, {0.1, 0.5}}] The ...
2
votes
2answers
133 views

How can I create a shortcut for a command in Mathematica?

I am using mathematica to write my physics homework, one thing that trouble me is that I need to enter lots of vectors. I usually type the name of the vector, "A" for example, and then hit "[Ctrl] 7" ...
0
votes
2answers
128 views

Block anti-diagonalize a square matrix?

In Mathematica there is a very convenient function called JordanDecomposition[]. It takes a square matrix A as an argument and ...
1
vote
1answer
113 views

Draw two curves and a surface

I'm trying to draw two curves and a surface, where one of the curves is to appear on the surface. Unfortunately the curves are drawn with very few points and appear extremely unclear. Is there a way ...
3
votes
1answer
61 views

Sort Unicode characters

Sorting ASCII phrases works fine: Sort[{"albatrob", "abo", "dict", "star", "mangel", "m"}] (*{"abo", "albatrob", "dict", "m", "mangel", "star"}*) But unless I'm ...
0
votes
2answers
523 views

Projectile motion in Mathematica using Euler's method [duplicate]

I need to write the equations of a ball in projectile motion (ignoring air friction) with an initial velocity of 40 m/s at an angle of 40° with respect to the horizontal. Specifically, I need to write:...
6
votes
2answers
213 views

Is there a way to detach/reattach the Frontend from a running Mathematica Kernel?

I perform long calculations on a fast remote machine running the Mathematica kernel, where I followed the very useful guide Remote Kernel Strategies to establish the connection. I wonder, however, if ...
0
votes
1answer
44 views

Writing a math formula to order results in a certain way [closed]

I am not very well educated in math and I have a math puzzle that I'm trying to solve. I have the following list and each object has 3 numbers. The first 2 numbers are better when they are as high as ...
6
votes
6answers
541 views

Find (longest) overlapping elements between two lists

I am trying to write a function f that returns the overlapped sublist where A ends with this sublist while ...
8
votes
0answers
122 views

TimeConstrained[Delete[Range[1],1]] causes kernel crash

Run these two samples of code here (AFTER SAVING YOUR CURRENT WORK): Do[ TimeConstrained[ While[True, Delete[{1}, 1]; ];, 0.1];, {100}] ...
2
votes
1answer
207 views

Polar color coding for complex function plots?

Having browsed this Q on plotting complex functions and the Zeta page, I don't see anything as nice as this plot from Matilde Marcolli's slides "Geometry and physics of numbers". Looks like ...
0
votes
1answer
88 views

Weird subscript name in output [duplicate]

One of my first times using mathematica, I'm getting a weird Subscript(1,0) output when I try to solve a derivative. What is going on and how can I fix this?
4
votes
1answer
518 views

How do I adjust error bar tick size with ErrorListPlot?

I'm making a plot of data points from an experiment and the error bars are quite small. I would like the vertical error bars to have wider horizontal lines so that they are easier to see. Are there ...
0
votes
1answer
211 views

Cauchy Principal Value integral- no result is obtained [closed]

I have a particular Cauchy Principal Value integral that I need to numerically solve for my thesis research. It is the following $$ \int_{-1}^{1}dx\frac{\mathbf{p}^{2}+\mathbf{k}^2-2|\mathbf{p}||\...
2
votes
2answers
168 views

Color points in ListPointPlot3D

I have some 3d points with coordinates and a value assigned to each point. I want to plot the points and depending on the value use a different color. I have tried to use the answer in ListPlot3D - ...
0
votes
1answer
50 views
2
votes
0answers
57 views

Finding basis of isotropic tensors of rank r

I am looking for a way to obtain a basis of isotropic tensors of rank $r$. Actually I am mostly interested in rank $8$ isotropic tensors but maybe you know already a simple algorithm in order to ...
1
vote
2answers
58 views

How to catch and fix a warning/error that goes away almost immediately?

I wrote the following code ...
-1
votes
1answer
80 views

I have several functions and how I know which one is the maximum in a certain range?

What I did are the followings These lines will generate a piecewise function pw which tells me the corresponding variable given an interval as follows: Now, I want to get: names of variable ...
0
votes
3answers
74 views

ReplaceRepeated made a single replacement where I expected multiple replacements to be made

This seems like a very simple action: {a, b, c, d, e, f} //. {r___, x_, y___} :> {r, 1, y} but it replaces only the first element giving ...
2
votes
0answers
50 views

Encourage SemanticImport to assume numbers?

I would like to import a CSV without specifying the data type of each column before hand. SemanticImport almost does it, but doesn't appear to recognize numeric ...
3
votes
2answers
216 views

How can I create a 3D representation of an object with known coordinates and adjacency table in mathematica?

Basically I want to create an object with specified coordinates and adjacency table, like in page two of this article. I'm completely new to using Mathematica, any help would be great! EDIT: So I ...
2
votes
2answers
185 views

How to generate a range of numbers

Is there a quick and dirty way to generate a list of numbers from 1 to some arbitrary large number in order such that the digits of each number are only 0's, 1's, and 2's? I tried doing ...
4
votes
2answers
174 views

How do I display function application with square brackets in traditional form?

If I type C[x, y] // TraditionalForm I get something that looks like C[x, y] But if I type ...
0
votes
1answer
104 views

Cannot figure out how to write a formula as input [closed]

I am trying to re-write some equation as input in Mathematica, but still cannot get it correctly.
0
votes
1answer
317 views

How to solve a linear system of 9 equations with 9 unknowns? [closed]

This is my current code and i'm not sure why it's not working. I am new to Mathematica, though. ...
2
votes
2answers
471 views

Check RUT (Rol Único Tributario) for numbers over 7 digits

In Chile the RUT (Rol Único Tributario) is a national identification number. Every RUT has a check digit modulo 11. The RUT has 7 or 8 digits plus a check digit or letter. I made this code that works ...
1
vote
1answer
57 views

Determine whether one value is divisible by another [closed]

How do I determine whether one number is evenly divisible by another in the case of large numbers, for example: 52^52 / 52!
0
votes
1answer
82 views

Factoring problem

Keep factoring and concatenating starting with 2 until we get a prime, i.e. 2 = 2 ; 22=2.11 ; 22211=7.19.167 ; 22211719167=..... and so on (the prime factors are arranged from smaller to larger and ...
5
votes
1answer
124 views

Rearrange an algebraic expression so that each variable appears only once

Mathematica gave me a solution to an equation in this form: ans1 = (b c)/(a - a c + b c) $\text{ans1} = \frac{b c}{a - a c + b c}$ From solving the same equation ...
1
vote
1answer
62 views

Error using NSolve function please help

I have tried to use nsolve to solve this transcendental equation for the bound state of a finite well.. For some reason mathematica is just returning my exact input back to me any ideas on how to ...
0
votes
1answer
277 views

MagiQuest Wand Identifier

My kids recently played MagiQuest, a game wherein people run around with "magic wands" that shoot out infrared light into sensors that activate different portions of the game. Each wand shoots out a ...
2
votes
1answer
338 views

Dataset: sort rows in descending order of first column

I am new in the Mathematica community and I have a probably easy question for you regarding how to sort a dataset as the following so that I have sorted the values in the fist row descending from 44 ...
3
votes
1answer
157 views
2
votes
1answer
424 views

Coupled non-linear differential equations

I have a system of coupled nonlinear differential equations to solve: $$ \frac{\partial m(x,t)}{\partial t}+v(x,t)\frac{\partial m(x,t)}{\partial x}=-\gamma \frac{\partial^2 v(x,t)}{\partial x^2}, \\ \...
3
votes
1answer
85 views

Replicate CommunityGraphPlot as a Graph

Is it possible to format a Graph object in a similar way to CommunityGraphPlot, but retain it as a Graph? I've been playing with FindGraphCommunities but I'm obviously missing some of the pre-...
0
votes
1answer
103 views
3
votes
2answers
166 views

Replace missing data

I have vectors of equal lengths where I want to replace the zeroes (missing data) with their preceding values. So far I have written: ...
0
votes
1answer
90 views

Simplifying code

I have a program where I solve the Lorentz-63 system (system of ODEs). I wish to generalize my program to make my code cleaner. Is there any way to create a function that works in a fashion such as ...
5
votes
1answer
97 views

Prevent evaluation of certain cells / code segments

I´m not quite sure if I ask a stupid question but I could not find an appropriate answer in the forum... I have a variety of cells (= code segments) in my notebook which I would like to evaluate in ...
1
vote
1answer
83 views

Value of event function not a real number

I am having some problems with handling an event during NDSolve. The event itself is simple, I am looking for when one of my coordinates, defined in ...
0
votes
1answer
78 views

ReadList and ToExpression

My dataset is like: id, feat_1, feat_2, feat_8, feat_9, feat_10, feat_11, feat_17, feat_18, feat_22, feat_2, target 1, 1, 0, 0, 0, 0, 1, 2, 0, 1, 0, Class_1 2, ...
0
votes
1answer
83 views

Selective update of mySQL database column

I would like to update several entries in a mySQL database which I use in combination with Mathematica. But the following code does not work: Map[ SQLUpdate[conn, "table_name","column2update", {1}, ...
12
votes
2answers
574 views

Interpolation on a regular square grid spanning a triangular domain

Bug introduced in 10.0 and fixed in 10.1 Context I am trying to identify contours of a function which is sampled on a cartesian grid within an irregular (triangular) region. Here is the data <...
4
votes
1answer
125 views

What are Epilog x-Axis Positions In BoxWhiskerChart (with BarSpacing option)?

I have a dataset that has a number of groups with overlapping sets. There is a point in the group within the intersection of the sets that I want to highlight by placing a marker of that point between ...
0
votes
2answers
117 views

Function with condition

I am starting my adventure with Mathematica. I would like to know if is there possibility to create function described by formula for example f(x):=1+2^n where 2^n < x. I have problem with this ...

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