1
vote
1answer
84 views

Are all of the numbers in my file legitimate hex numbers

I have about 10,000 hexadecimal numbers (32 digits each) in an excel file, in one column. I want to verify that all of them are indeed hexadecimal number and that no other characters are present. My ...
0
votes
1answer
81 views

Differential equations DSolve constant issue

After using DSolve to a set of differential equations, three constants arise. They are C[1], C[2] and C[21]. I have checked thoroughly that there are no C[3], C[4],....C[20]. It is quite mysterious to ...
2
votes
1answer
88 views

Strange Issue with RowBox

Can someone explain why this notebook [RANGEWORKING.nb] ...
4
votes
1answer
127 views

Output function control and manipulation for efficient computation [closed]

I have taken note of a similar post related to modifying function parameters. I tried to adapt Kuba's solution to this post but I can't get it to work. I will illustrate my problem using a similar ...
2
votes
1answer
482 views

Show plot legends for multiple curves in one plot [closed]

I have 5 curves, figure1a0, figure1a001, figure1a01, figure1ae01, and figure1ae001,. I display all these curves in one plot with Show. I want to give a label to ...
3
votes
1answer
174 views

WSTP (formerly MathLink) problem

I recently set about to re-compile some old (2008-2009) applications that use MathLink in preparation for creating new, modified versions. Mathlink has been deprecated but WSTP seems like a fairly ...
17
votes
1answer
1k views

Is Mathematica `ContourPlot` function really so efficient?

I wanted to find the roots of the function $f(x,y)=\sin(3.2x)\sin(1.3y)-2.1 \sin(1.3x)\sin(3.2y)$. This is what the function looks like: ...
0
votes
0answers
40 views

How to evaluate NMinimize inside a function

I want to define a function that returns a sum of differences of some points to a given function. To obtain these differences I would like to use NMinimize, but if I implement that straightforwardly, ...
0
votes
1answer
50 views

Why Table is not giving me the same sequence for eigenvalues of matrix

Let consider a matrix and evaluate the time dependent eigenvalues M[t_]:={{Sin[t],Cos[t]},{t,t*t}}; e1[t_]:= Eigenvalues[M[t]] Now If I evaluate ...
0
votes
2answers
341 views

Convolution of a piecewise function

I want to find the convolute the the functions in the Convolve command ...
1
vote
1answer
62 views

Error with using SortBy in a Map [closed]

I have a data set in the following format: SomeData = {{a, 1, 2}, {b, 2, 3}, {c, 3, 4}, {b, 1, 9}, {c, 1, 10}, {a, 2, 3}, {a, 3, 8}, {b, 3, 4}, {c, 2, 9}}; The ...
10
votes
0answers
187 views

Efficient image stacking

I have a list of lists of images that I would like to stack and create mean images for each list of images. Images are .jpg files 2592x1944 pixels large. Each list ...
0
votes
1answer
68 views

Vector Analysis in Version 8

Silly question. Why does Needs["VectorAnalysis`"] Grad[Sin[x^2 + y^2], {x, y}] give the error Coordinates::invalid: "{x,y} is not a valid coordinate system ...
5
votes
1answer
131 views

Specifying WorkingPrecision in LogLogPlot produces invalid plots [duplicate]

I seem to have found a bug with LogLogPlot in Version 10. If I specify a working precision, the function produces total garbage. Here is a simple example. The first ...
5
votes
2answers
213 views

Drawing a path which realises the diameter of the graph

So I enter a (0,1) adjacency matrix and I get the following graph: The diameter of this graph is 4. How can I ask that two vertices which realise this diameter be drawn with different filling ...
1
vote
1answer
258 views

How to impose normalization condition (not initial condition) on DSolve or NDSolve?

I have a set of differential equations (or DAEs): $\begin{cases} 5x_{2} + 3x_{4} + 3x_{5} = \frac{dx_{1}}{dt}\\ 5x_{1} + 5x_{2} + 5x_{3} + 3x_{4} + x_{5}= 0\\ 3x_{2} + 3x_{4} + 10x_{5} = ...
1
vote
0answers
58 views

Is it possible to circumvent this overflow?

I'm trying to evaluate the following function numerically: $ f(A,B)=\frac{2A\pi ^{5/2} (-1)^B}{(A!)^2B!} \, _4\tilde{F}_3\left({\frac{1}{2},1-A,1-A,1-B\atop ...
1
vote
1answer
129 views

How can I copy & paste cell styles?

In Mac's mail app the key shortcut "command + option + c" gives a copy selected text style and "cmd + opt + v" pastes the style. Is there a way to achieve this with cell styles? The keyboard part is ...
6
votes
2answers
318 views

Evaluating complicated trig without resorting to numerical methods

I have an angle theta given by Kx = (2/Sqrt[3]) ArcSin[Sqrt[3/10]]; Ky = (2/3) (ArcCos[(1/5) Sqrt[7/10]] - Pi); theta = Cos[ArcTan[Kx, Ky]]; This evaluates, by ...
0
votes
1answer
110 views

Error Using Mysql In Mathematica

I'm using Mathematica, and accessing mysql through mysql (Connector/J). When I try to update a field in my table using WHERE statement, all the rows get updated ...
10
votes
1answer
285 views

Context of localised (dynamic) symbols

When you localise a symbol with Module, the created unique symbol is usually in the current context. There seems to be an exception to this which has further ...
2
votes
1answer
65 views

Plotting Vectors in Mathematic at lat/long positions

I have some current data that I want to plot in Mathematica. The first two columns are the latitude and longitude respectively (longitudes are negative b/c it is west of the prime meridian and all ...
2
votes
3answers
579 views

Plot a table of lists

I want to make a point plot of a table with lists in it. Assume I have data like this: data={{1,2,3,4},{5,6},{1,5},{2,4}}; and now I want to make a point plot ...
1
vote
0answers
88 views

How to make Show work in Mathematica 10 Kernel [closed]

Wolfram Research says it no longer supports JavaGraphics in Mathmatica 10. This is very bad for people who prefer the Kernel to the FrontEnd. However, I am still able to get it to work. Show ...
0
votes
2answers
57 views

Table results within loops

I have the following code. ...
0
votes
1answer
75 views

Derivative inside a Series [closed]

I have a function defined by a sum, which I would like to differentiate. For example: ...
-1
votes
1answer
88 views

How to assign variables to selected roots of a polynomial equation? [closed]

I have a polynomial equation like the below, and I want to assign variables to the roots that are not pure imaginary. How I can do this? ...
16
votes
3answers
2k views

Can Mathematica's random number generation be improved?

Performance on Random Number generation is intolerable. Whenever you need many deviates from the same distribution but with different parameters it takes forever. Here is a thread on Poisson ...
1
vote
1answer
110 views

Solving equations using algebra [duplicate]

Has anyone ever solved an equation for students using algebraic steps? For example, you start with the equation. 2x+3 = 5 Then you show subtracting 3 from both ...
4
votes
2answers
234 views

How do I change the size of an imported picture in an animation?

My code right now plots a function, and animates an image moving along the curve of the function. I want to reduce the size of the image for this animation but I can't figure out how. If I try to ...
4
votes
1answer
251 views

Pattern matching multiple symbols names and powers

Seemingly a relatively simple problem, I can't seem to find a solution... I want to build a pattern that will match any symbol whose name starts with V, and is elevated at any power. Something on the ...
2
votes
0answers
61 views

Precision loss in FourierDCT

I have high precision data that I want to do Fourier transform with, but it looks like the precision is lost dramatically. ...
0
votes
1answer
142 views

Integrating spherical harmonics

I am trying to simply check the integration/normalization condition on the SperhicalHarmonic functions that are built into Mathematica. So basically, I just want to check that the following integral ...
4
votes
2answers
180 views

Problem with ParametricNDSolve

i have a strange problem with ParametricNDSolve. Given the sistem of differential euqations ...
0
votes
1answer
43 views

Numerical error in DSolve [duplicate]

I'm solving the 1D Poisson equation and am getting some funky numerical artifacts in the solution. ...
6
votes
3answers
156 views

EasterSunday replacement in Mathematica 10

The Calendar package, now obsolete, had functionality for "special dates", in particular EasterSunday[]. The documentation says it's been subsumed into Wolfram ...
4
votes
1answer
93 views

While stops running in a Dynamicmodule

I made this: ...
0
votes
1answer
44 views

How to get array/list of results of RotationMatrix?

For most other functions, passing in a list of arguments will return a list of results. E.g. t = Range[0, 10]; m = N[Sin[t]] returns ...
2
votes
2answers
179 views

How to plot points with error circles on map with latitude/longitude grid

I am currently working on a project to model the location of icebergs in the northwest atlantic. When an iceberg is sighted, an error circle is plotted around it (with a bivariate normal probability ...
4
votes
2answers
108 views

Can I modify Ctrl— to insert Indexed expressions?

For me, Indexed[x, n] is a much more useful and versatile construct than Subscript[x, n]. I would therefore like to modify ...
1
vote
1answer
190 views

How to evaluate some parts of an expression inside Hold? [duplicate]

I want to return a Hold expression but with some parts pre-evaluated. The easiest way to explain this is probably through code example. Here is what I have ...
3
votes
2answers
141 views

How do I apply a ColorDataFunction[] to a grayscale image? [duplicate]

Suppose I have a 2D array im of real values between 0 and 1, representing a grayscale image. I can turn im into an image very ...
0
votes
0answers
50 views

Notebook does not open [duplicate]

When I save a simple notebook , with the sum 2 + 2 , it does not open at all or with double-click or by pressing CTRL + O. Have reinstalled Mathematica 3 times and did not work. I put the settings in ...
3
votes
2answers
79 views

PredictionBands and the presence of {0,0} point

We know from this post, that the default fitting method cannot handle data with a {0,0} point, and that there are alternative methods. But, with these alternative methods, the prediction bands ...
8
votes
2answers
368 views

Is there a bug in FindClique?

If h is a graph, FindClique[g, {n}] should return a clique on exactly $n$ vertices if one exists in ...
1
vote
1answer
110 views

DSolve with Absolute Value

When playing around with DSolve, I enter the following: DSolve[{Derivative[1][y][x] == x + Abs[x]*y[x]}, y[x], x] The output is: $$y(x)\to e^{\frac{1}{2} (x ...
1
vote
1answer
73 views

How to change the expressions in terms of a specific variable?

I have a series of analytical equations: ...
-1
votes
1answer
88 views

Define a function and then integrate and plotting of the solved function [closed]

First I want to solve for $n_{0}$ for a fixed value of $n$, lets say $n=1$ $$ n= n_{0}+ \dfrac{1}{2}\int_{-1/2}^{1/2}dq\left(\dfrac{e_{q}+Un_{0}}{\hbar\omega}-1\right) $$ where $e_{q}=2[1-cos(2\pi ...
1
vote
2answers
120 views

Conditional Convolution

I was hoping to incorporate an If function into a Convolve operation, as in ...
0
votes
1answer
103 views

Method that combine LinearSolve and Dsolve for a set of differential equations?

I have a matrix for example: $\begin{bmatrix} 0 & 5 & 0 & 3 & 3\\ 5 & 5 & 5 & 3 & 1\\ 0 & 3 & 0 & 3 & 10\\ 1 & 3 & 2 & 3 & 10 \\ 1 ...

15 30 50 per page