# All Questions

72 views

### How to loop in reverse order?(e.g. for i from 10 to 1) [closed]

I have a list F = {382.856, 638.53, 915.482, 1192.44, 1469.39, 1746.34, 2023.29, 2181.91} And I want to use it to calculate V: I think it should be something ...
711 views

### Finding “Maxima” and “Minima” on a B-Spline

I need to find the "Maxima" and "Minima" on a B-Spline or more correct the points where the 2nd components of the derivate equal zero. For example: ...
85 views

### How to plot the product of the NDSolve result and any known function

How can I plot the product of the NDSolve result, e.g. x[t]/.solution and any known function, for instance, ...
152 views

### How can I create a list containing the normalized element-by-element product of two given lists?

I have to calculate: How can I create such a sum? Do I have to set the factors of each term manually (one by one), like G1 = 1, H1 = 1, G2 2, H2 = ....? ...
238 views

### How can I get a PieChart to be colored as I wish?

How to use the value of a funtion[label] to assign color to a piece of the pie? (edited after answer of kguler ) My dude is how to control the colors in ranges of a function of [labels] In this way ...
82 views

### About how Mathematica understands the branchcuts of the complex logarithm [Part 3]

One understands that for the function $\log(z^2+a^2)$ Mathematica implicitly puts the branch cuts to be starting at $\pm ia$ and going up/down respectively on the imaginary axis. The phase of this ...
491 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: ...
42 views

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

/edit Nevermind i figured it out, i now have: ...
118 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 ...
34 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: ...
181 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 ...
542 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 ...
155 views

### How to solve this integral equation?

I am trying to solve for x the integral equation : ...
58 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 ...
116 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 ...
171 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: ...
395 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 $3\times3$ ...
198 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 ...
123 views

### When to use GenerateConditions -> True

Many functions, usuallly those involving integration, take a GenerateConditions option which often defaults to False, or at ...
194 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: ...
221 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 ...
229 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 ...
286 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 ...
101 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 ...
286 views

### Variable number of nested variable-range sums

I would like to express the following nested sum in Mathematica: $$S(m,j,N) = \sum_{k_1=m+j-1}^{N-1} f(N,k_1) \sum_{k_2=m+j-2}^{k_1-1} f(k_1,k_2) \cdots \sum_{k_m=j}^{k_{m-1}-1} f(k_{m-1},k_m)$$ ...
467 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 ...
144 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 ...
429 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: ...
356 views

I have the following $\;3\times3$ matrix: $\left( \begin{array}{ccc} 0.04 -0.4 b & 0 & 0.04 -0.4 b \\ 0 & -0.08-1.2 b & -0.06-0.9 b \\ 1.04 -0.4 b & 2.08 -0.8 b & 0 ... 1answer 232 views ### Surface area of intersecting spheres Given a sphere of radius 1 centered at the origin and$n$spheres with radii$r_i$centered at predefined coordinates,$c_i$, in space, I am after the surface area of the unit sphere that is not ... 1answer 176 views ### Integrate does not accept my integrand expression I want to calculate the symbolic integral, but I could not obtain the final results from Mathematica. ... 0answers 86 views ### Inhomogeneous phase-portrait with StreamPlot [duplicate] I have a problem with a must-be simple streamplot. The potential function governing the motion is U, and I have the following code in Mathematica: ... 1answer 286 views ### Understanding of method for NDSolve I used automatic method for NDSolve. Then I asked myself - which method Mathemathica prefered? I got an answer for this question on this forum, that I need to use: ... 1answer 69 views ### How do I visualize the result of EdgeColoring[g]? Combinatorica has a heuristic edge-coloring function EdgeColoring. When I execute it on a graph, the result is a list of integers. My guess is that an integer$i$... 2answers 97 views ### Finding all instances of length$N\$ common subwords in two strings

Given a pair of strings, I'd like to return a list of all common subwords of a fixed length of "n" characters (i.e. contiguous subwords of length "n" that occur in both strings), allowing for ...