# All Questions

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 ...
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 ...
88 views

### Strange Issue with RowBox

Can someone explain why this notebook [RANGEWORKING.nb] ...
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 ...
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 ...
174 views

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 ...
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: ...
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, ...
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 ...
341 views

### Convolution of a piecewise function

I want to find the convolute the the functions in the Convolve command ...
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 ...
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 ...
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 ...
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 ...
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 ...
258 views

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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
57 views

### Table results within loops

I have the following code. ...
75 views

### Derivative inside a Series [closed]

I have a function defined by a sum, which I would like to differentiate. For example: ...
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? ...
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 ...
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 ...
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 ...
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 ...
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. ...
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 ...
180 views

### Problem with ParametricNDSolve

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

### Numerical error in DSolve [duplicate]

I'm solving the 1D Poisson equation and am getting some funky numerical artifacts in the solution. ...
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 ...
93 views

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