# All Questions

48 views

### I want to get some inputs from user [closed]

I'm new to mathematica. i have a small project: get an equation , a number n, a number x and a number y and a number h, then using euler formula calculate nTh iteration ... My code is : ...
48 views

### Bug in parallel computing

The following is a simplified example. We construct a library function f and another library function g, in which the library function f is called. ...
74 views

### Derivative of Vectoral NDSolve Interpolated Function / Rule Solutions,/., and Vector NDSolve [duplicate]

I need to find the instantaneous phase and instantaneous frequency for a rotating system. I am having difficulty making the math work with interpolating functions. First, here is a problem without ...
34 views

### Plotting the real positive solution to a parametric equation [duplicate]

I have the following parametric equation $$x^2-a=0$$ where $a$ is a given parameter. I would like to plot the nonnegative real root ($\sqrt{a}$) using NSolve as $a$ varies from $0$ to $1$. Can ...
56 views

### How to ensure efficient order of operations for rules, slots, substitutions?

I need to calculate several functionals Q[[t]] of a pdf f[x]. ...
26 views

### How to implement a tensor system using indices and Einstein notation?

There are several function like TensorProduct and TensorContract doing basic tensor operations by regarding tensors as lists ...
72 views

### My code does not give the same results on mathematica 9 and 10

I have developed last year an algorithm using mathematica 9. In this algorithm, I remember that coordinate system of Image and Graphics are not the same. However, in mathematica 10 the coordinate ...
74 views

### Incorporating the minimum and maximum of the function in a Dynamic plot

I'm working on my project for class and it's supposed to be a graph that can take functions from the user and display it along with finding the max and min of the graph. But I just don't know how to ...
22 views

### Plotting the vector field of a function [closed]

$f(x, y) = x^2y - y^3$ In := Grad[{x^2*y - y^3}, {x, y}] Out := 2 x y, x^2 - 3 y^2 In := VectorPlot[{2* x* y, x^2 - 3 *y^2}, {x, -3, 3}, {y, -3, 3}] Do I ...
30 views

### Reverse x and y in pairs data set [closed]

I have a list of data {{x,y}}={{2,4},{5,6},{2,1},{7,4},{3,4},{4,6}}.Mathematica automatically plots x in horizontal axis and y in vertical axis. I would like to switch axis position such that new ...
74 views

### UPDATED CODE: Need to utilize FindFit with specified x variable values [on hold]

I have a function that I need to fit multiple (5) input values for, but I only have the function defined for 12 specific variable x values due to the need to ...
36 views

### Why is there a seeming discrepancy with the expression Cofactor?

I was trying to find out the cofactors of a square matrix. Then I came across the command Cofactor in Combinatorica package. ...
44 views

### A more suggestive name for a useful utility Query?

Ideally this utility query to project only the named keys involved in the function mappings from relational tables with many columns would be built in the language. I use it a lot: ...
18 views

### How to find the intersection of a Line with the boundary of a Region?

Given a 2-D Region $\Omega$, i.e. RegionQ[\[Omega]] && RegionDimension[\[Omega]] == 2 is ...
105 views

### Why does this function inside FindRoot fail to evaluate?

Can someone help me understand why function mu found below does not execute when everything before it seems ok. ...
30 views

### RegionBinarize distance parameter has no effect

I'm trying to segment an object from background in noisy micro CT data. The original 3D volume data looks like this: ...
55 views

### ListPicker delayed output

I'm trying to make a wrapper for ListPicker that delays updating the list unless Ctrl or Shift is released. The aim is to allow nested ...
55 views

### Incomplete Integration in Area

Area[2 Sqrt[(1 - p^2)^2 - r^2], {p, 0, 1}, {r, 0, 1 - p^2}] is able to perform only the integral over r, leaving the integral ...
24 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: ...
7 views

### Can someone tell me how I can paste Mathematica code into a message here without losing the math formatting [migrated]

Thanks in advance. There is a sizable chunk of code would like some help with. But I need to understand how to paste it in here properly.
23 views

### Save a result containing HoldForm to a file

This is the workflow I have. Basically, I want the outputs of the polynomials I computed are in a specific order. (It is not the same one here, this is just an example.). ...
34 views

### Help with Multivariate ProbabilityDistribution

I wish to obtain numbers from ...
76 views

### Computing with matrix differential operators

I am looking the achieve a working set of Mathematica functions that would allow me to take products, commutators, etc. of (2x2) matrix differential operators and apply them to vector-valued functions ...
87 views

### How can I transfer colors from first image into second image? [duplicate]

How can I transfer colors from first image into second image, where every object from the first image should take the same object's color from first image. This images are only an example. this is ...
17 views

### Binomial Regression where n > 1

I am not well versed in Generalized Linear Models, but am trying to use this approach to model some discrete data. I have binomial data where the sample size for each observation is the same size, ...
54 views

### Change default output font globally

I'd like to change my default output font to "Helvetica Neue" in version 10. The following shows the only thing I have found in Option Inspector, which would ...
46 views

### Konno model (linear programming applied finance ) [closed]

How Using the model of Konno and Yamazaki ( linear programming model applied finance and alternative to Markowitz model) in wolfram mathematica ? I want to ride a stock portfolio that minimizes risk ...
33 views

### NIntegrate with units: unable to determine the units of quanitites that appear in the input

I want to integrate Planck's law of radiation in a certain wavelength intervall with units. I define some constants: ...
50 views

### Strange constants in a PDE solution by DSolve

I'm solving the following PDE: DSolve[F''[ξ] + (Ω^2 - M^2 Exp[2 α ξ]) F[ξ] == 0, F[ξ], ξ] And Mathematica gives a general solution in terms of modified Bessel ...
40 views

### How to assign equation solutions to variables [duplicate]

I have 12x12 Matrix with which I have to solve the equation below: ...
43 views

### How we can find shear and torsion equations for non homogeneous cross sections.? [closed]

when we use FDM to find torsion of square section with one homogeneous material we can do it easily by mathematica "see the attached file" But what will happened if we have the same cross section with ...
234 views

### representation of custom deformation on a meshgrid

I am trying to represent 2D deformations on a rectangular grid. In Mathematica 10, there is a method to solve the elastic differential equations and then represent the deformation as presented here: ...
123 views

### How can I create a minimal surface with trefoil knot as inner edge and circle as outer edge?

This minimal surface is the subject of Michael Foster's beautiful wood-turned sculpture "Inversion" (see http://breezyhillturning.com/styled-2/photos-2/index.html). In addition, how can one create 2D ...
62 views

### Plot table versus table [duplicate]

I have two tables like: nex1 = Table[l3*10^3/4*10^14, {l3, 1, 30, 1}]; nex2= Table[l4, {l4, 1, 30, 1}]; How can I plot nex1 versus nex2 so that nex1 is x axis ...
55 views

### How to plot a ternary plot? [duplicate]

Does anybody know how to plot a ternary plot (equilateral triangle)? Suppose, I have a list of lists like this (triplets): ...
235 views

### Bug in ArcLength?

With Mathematica 10.0.2: ArcLength[Line[{{0, 0}, {1, 0}, {2, 0}}]] ArcLength[Line[{{0}, {1}, {2}}]] (* 2 *) (* 2 *) However, ...
102 views

### Can't type in notebook in version 10

After upgrading to version 10, I sometime get into the situation that I can enter nothing to the notebook. The Mathematica seems alive but it doesn't take any input from the keyboard. I tried to quit ...
36 views

### Robust (White) estimation with LinearModelFit?

You can make a robust estimate (White) by LinearModelFit or GeneralizedLinearModelFit? Thanks.
73 views

### How to find the direction of the outward normal in a point of the boundary of a 2D region?

Suppose we have a domain $\Omega$ such that RegionQ[\[Omega]] is True and ...
52 views

### Function that adds up every element in an array [closed]

I'm trying to write a function that adds up every element in an array up to a specific index. I've tried the following: ...
88 views

### ReplacePart equivalent for Associations

I have a fairly complicated Association. I wish to use/create a function such as ReplacePart to operate on certain Keys within this multi-level Association. Here's ...
60 views

I am calling ...
114 views

### GPA calculation from a set of randomly generated marks obtained

So, this is a homework question posed by my teacher: "A student has 10 courses. Find the ceiling value of the obtained marks and corresponding grade according to the following data Print the result ...
54 views

### Different results with Plot option “Evaluated” in V9 and V10

Consider this example: Plot[Table[BesselJ[n, x], {n, 2}], {x, 0, 10}, PlotLegends -> {"n=1", "n=2"}, Evaluated -> True] The results in MMA v9 & V10 ...
49 views

### Plotting Earth's position with units

I'm trying to plot the Earth position with the Sun in the origin. I have two lists like this: ...
101 views

### Help with building matrices

I am a complete beginner in Mathematica and I have a small problem. I have this three matrices (A,B and C) and with them I have to build larger matrix M which looks like this. What would be the ...
49 views

### Regression with 3 variables

I'm trying to find a function starting from its values but I can't find anything related to functions with 2 variables and I don't know how to go on. So, given this sample data, I'd like to know how ...
58 views

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