# All Questions

488 views

### Data filtering using Butterworth filter

I want to filter data using Butterworth filter. I am currently using Matlab and I want to know how to do it in Mathematica. I have the following data: ...
41 views

### Plotting a StateResponse inside a loop for some reason gives an error [closed]

/edit Nevermind i figured it out, i now have: ...
116 views

### Revert y-axis in RegionPlot

I have the following code: ...
95 views

### How to generate a list with a loop, and put it into a variable?

I am pretty new to Mathematica and to coding in general. I want to do a very specific thing, but I unable to do it. Please explain in detail how I can make this work. Here's the details on what I am ...
33 views

### Correct use of Mathlink's MLGetRealList

I am attempting to use Mathlink from C. I have managed to return single values from mathlink to my c program, but I am having trouble with lists. Consider the Mathematica operation: ...
180 views

### Controlling spacing of histograms in Histogram3D

I have five histograms, hist1 = Histogram[data1, 20], to which I append {1, 2, 3, 4, 5} via ...
520 views

### FindRoot in range

I am trying to find all roots in a range, using y /. FindRoot[Sin[y] == 0, {y, #}] & /@ Range[7] which gives ...
154 views

### How to solve this integral equation?

I am trying to solve for x the integral equation : ...
57 views

### TableDirection in TableForm

I got confused about what does "the outermost dimension" and "the first dimension" mean in the document I snipped. Does it mean row or column?
108 views

### an NIntegrate inside a manipulate in mathematica was working and suddenly won't work now. it says indeterminent and it doesn't make any sense why

my title says pretty much everything heres what I'm entering. NumericQ returns a false value but it was true before. Im loosing my patience because this is so ...
114 views

### How to do assignments through MathLink?

In Mathematica I can make the assignment 'foo = bar' with Set[foo,bar]. However, if I try to evaluate 'Set[foo,bar]' through MathLink then it appears that MathLink gets stuck while trying to read ...
159 views

### Issue with Set function

Tables often come with column headers. Indexing the columns with the header is a natural thing to do. Although a proper dictionary is the usual solution in such a case, I find it often practical and ...
95 views

### Manipulate executes twice [closed]

I need help, guys! Here the script: ...
393 views

### Select cases from a list

I have a list in the form : {1,1,1,0,-1,-1,1,1,1,0,0,0,0,-1,-1} No I'm trying to select only those sequences which start with 1 have a zero (or many zeros) ...
205 views

### How to select the first “lowest” (first valley) number in a list?

I would to select the first valley of the list of coordinates below. It should be {3, 1}. ...
156 views

### X-Y scatterplot

Hi I have a simple question. How do I plot the following with Day 1 as my X axis and Day 2 as my Y axis? I need the 22 variances plotted according to the Day they were taken from (these were ...
94 views

### Matrix Operation

I have a $3\times3$ matrix A, and a function sTrans that outputs two $3\times3$ matrices in a list when given a $3\times3$ ...
197 views

### Little triangles appearing in a Mathematica region plot with “opacity” saved in a PDF file [duplicate]

I am trying to produce a region plot of many functions, but Mathematica keeps showing me the little triangles when I save it as pdf. I have seen other solutions which fix the problem with PlotStyle-> ...
53 views

### Conjugate of InterpolatingFunction?

From NDSolve, I got this: {{a1 -> InterpolatingFunction[{{0., 40.}}, "<>"]}} What would be a sensible approach to ...
104 views

### Manipulate for Electric Field

I'm kind of new to Mathematica but I'm getting the hang of it slowly. Anyways, I'm trying to do a project on the electric field of two particles so my professor helped me with this code (sorry in ...
79 views

### Find the values of parameters so that the matrix is symmetric positive definite

Good evening , I have a matrix 20x20 in symbolic form. The matrix depends on 5 parameters (a,b,c,d,e). I would like to get the interval of each parameters that ensures that the matrix S is symmetric ...
121 views

### When to use GenerateConditions -> True

Many functions, usuallly those involving integration, take a GenerateConditions option which often defaults to False, or at ...
191 views

### Generating the set of all strings within a fixed edit distance of a initial string?

Provided a starting string initialString, and a particular alphabet of allowed characters {"A","B","C","D","E",...}, how can I ...
113 views

### Loading StatisticsLibrary

I need to use a number of functions from theStatisticsLibrary namespace. Since that is a bit of a mouthful I would like to import it, but I get errors: ...
220 views

### How can I avoid getting the error message Goto::nolabel in my code?

If anyone could suggest a reason why Label[begin] ... Goto[begin] would return Hold[Goto[Begin]], and (better) how can I avoid ...
224 views

### Overlay Rectangle on a ListPlot

I have a ListPlot of 100 data points in the range of 0 and 1. Now I'm trying to find a way to overlay (four) rectangles onto the listplot in 0.25 steps horizontally. Essentially I just have BinLists ...
285 views

### Importing data from excel and assigning a variable to each of its columns

How should I assign variables to the data imported from excel containing 3 columns which are time, mean and standard deviation. I want to perform operations on the three variables to get new ...
99 views

### Ticks don't display on Y-Axis of Histogram when using PlotRange

I have a histogram, if I create it without specifying the PlotRange it works fine and the ticks on the Y-Axis are displayed ...
180 views

### Strategies to find curves on messy data using FindCurvePath

I have a set of data points that correspond to roots of a transcendental equation with respect to a parameter (the abscissa) which, by the properties of the system, define continuous curves (might be ...
281 views

### Variable number of nested variable-range sums

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

### Efficient JSON parser for Mathematica

Im looking for a efficient way of parsing JSON data in Mathematica. I am having a lot of problems with ImportString because it uses Java, is too slow, and uses too ...
139 views

### How to sort the adjecency matrix of bipartite graph so to have two off-diagonal blocks

In a bipartite graphs there are two class of nodes, say A and B. Each node of class A may interact only with nodes of the class B, and viceversa. The corresponding adjecency matrix is thus composed by ...
73 views

### Solving for a charge distribution from a dipole moment [closed]

I've been looking around but I haven't been able to find any way of solving this conceptually simple problem. In short I am trying to find the charge density in a dielectric in an external electric ...
425 views

### Where can I find a dark stylesheet for mathematica?

The default white is very tiring for the eye after some hours.
144 views

### Expand expression into quotient of negative power series

I have a function T(z) and want to expand it to the following form: At the end I want to have a list of equations, which can calculate a0, a1, a2, b0, b1 and b2 with different values of h1, h2, ...
72 views

### How can I troubleshoot a PDF that fails to import?

I'm trying to import a PDF file whose text I'd like to parse, but I'm getting an error with no explanation: ...
350 views

398 views

### Nothing appears in simple plot

I'm trying to get the following simple code to work. (The code is just supposed to graph the norm of the second derivative of a vector function). ...