# All Questions

116 views

### How to make InverseFunction work on function defined with restriction on arguments

This example works to define InverseFunction on the first argument of a function ...
67 views

### kernel shuts down during listplot [duplicate]

In at least the following situations, I have experienced that the kernel has shut down during evaluation. The thing is that there is no message at all when it shuts down. ...
714 views

### I want to calculate the pixel values of an image and export to a standard format

After finishing a few tutorials, I thought I was ready to calculate the pixel values of a large (smaller numbers 20x20 used here) image and export to a standard format (.jpg) but my code doesn't work. ...
1k views

### How to partition a list of numbers in two lists of numbers such that each lists elements sums up to the same number?

I have the following list of squares. {1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225, 256} Their sum is $1496$, I want to make two partitions ...
89 views

### Issues FindRootPlot command

I've had some fun playing around with FindRootPlot for a simple system of equations: ...
418 views

### How to find Image Size of a control object?

I want to find the ImageSize or at least dimensions of any control object irrespective of it being an image or an any other control such as ...
93 views

### creating some smooth density functions

I would like to create some density functions based on some distance measure $D$. As a base density function lets say I have a Gaussian density $f$ with mean $-1$ and variance $1$. I would like to ...
131 views

### Bound on number of function evalulations in FindMinimum

I am minimizing a nonlinear constrained problem using FindMinimum. The problem involves about 200 variables and the function is a black-box which cannot be ...
183 views

### Writing NDSolve-like functions

I've been using Mathematica for a while now, and there are multiple common tasks that I end up doing. I'd like to learn how to convert them into functions so that I can store them in some file and ...
503 views

### Animation is jerky, but slider is not

When I do the following simple animation (from the book Mathematica Navigator, p. 316) the slider control changes the image smoothly, but when I play the animation it is jerky. Is there anything that ...
125 views

### Esc-esc for special characters and autocomplete in Mathematica 9 [duplicate]

I recently upgraded to Mathematica 9 and have noticed a slightly annoying behavior that I was looking to remedy. In the past I would type special characters, e.g. ...
124 views

### Why DateDifference returns machine number?

Is there any specific reason why DateDifference cannot give an exact number in this case? ...
2k views

### How to do the log scale plot for ListContourPlot

My current code is: ...
408 views

### Display a number in Mathematica 9 in periodic form

I want to display a rational number in Mathematica in periodic style. PeriodicForm isn't working anymore. It worked in Mathematica 5 and now I'm using Mathematica ...
101 views

### Cell copy results in jaggy, aliased output

When I copy a cells by selecting them from the collapse bars on the right, then using the context menu option "Copy", the pasted image of plots is not anti-aliased and in general the text seems to ...
259 views

### Iteration process involving several functions

I would like to carry out a following iteration process: Apply function f1[a_,b_,c_,d_] to a starting list l1={a1,b1,c1,d1}, ...
446 views

### How can I make a cell that contains an image which can be shifted?

When you're looking at some help pages, they may have cells containing images which can be shifted within the cell by left-clicking and dragging the mouse. Here is a sample: ...
121 views

### Function to differentiate between date pattern and specific string format

I'd like to write a function that behaves one way when the argument is a Mathematica date, such as {2013,12,15}, or with added hours, minutes and seconds if ...
118 views

### Frontend coloring of Table[x, {x, 0, x}]

I have a small question about how the Mathematica frontend colours in the variables that appear in (wrongly written) iterators. More specifically, I'm intrigued by the colour of the third ...
396 views

### How do I label contour lines that are superimposed on a 3d plot?

I need to generate a 3D plot of a function, say $z = \sin(x)\cos(y)$, with contour lines drawn at specified intervals. I also want to label each contour line with its $z$-value. I have discovered how ...
230 views

### How to create a SparseArray satisfying multiple conditions on Parts and Elements of a Matrix?

I have a matrix m1 of size $3 \times 19$. Rows $1$, $2$ and $3$ represent $3$ different groups, and columns represent $4$ different blocks: block1 - columns $1$, ...
227 views

### Variable length list with # and [[i]] as elements

I need to create a list that as an input receives the number $N$ of elements that it will contain and that returns: ...
233 views

### Omitting singularities from plot by specifying them in range

See the Mathematica 'basic plotting' documentation: http://reference.wolfram.com/mathematica/tutorial/BasicPlotting.html Scroll down to the third plot on that page, which says the following: "The ...
198 views

### Passing a joined list of symbols for Module or Block to treat as its own local symbols

The Question I'd like to write a function which itself takes a list of symbols, e.g. Foo[{x, y, z}] to pass to Module ...
239 views

### Mathematica won't simplify multiplication by zero

I'm getting a huge output, but it appears that almost every term should actually be zero, unless I'm misunderstanding the expression. For example, part of the output reads ...
534 views

### How can I scale a plot in vector graphic or PDF form?

I am not at all a computer graphics expert, but it seems that portable document format (PDF) files have a "native size," even though they may (and usually do!) contain vector graphics that can be ...
78 views

### Optimize recurrence output

I have recurrence and I need to calculate first $N$ members of the sequence ...
139 views

### Quickly pruning elements in one structured array that exist in a separate unordered array

I have two lists, which we'll call testList and modifiedTestList. The first list looks something like this: ...
262 views

### Import numeric data into Mathematica

I have a C++ program that outputs a set of numbers at each time step. A blank line separates successive time steps. Here is an example of my data format: ...
113 views

### Error message from V6.0.3 on Mavericks

With Mavericks, everything works fine except saving documents -- then I get this error: Internal self test error MacDialog | c | 2 Fixes? Ideas? Any help appreciated.
274 views

### How to restore default seed generation in SeedRandom[] when specifying method?

I want to generate low-discrepancy sequences and for that purpose I use SeedRandom[], like: ...
1k views

### DSolve to solve a system of differential equations [duplicate]

I need to solve a system of differential equations as follows: ...
130 views

### How to solve system of differential equations of arbitrary order (symbolic tensors)?

I am interested in solving systems of ODEs symbolicly, keeping things with arbitrary dimensions for clarity. For example, assume that $x, f(x) \in R^N$ and $A \in R^{N \times N}$, how do I solve ...
600 views

### Swapping elements of list

Say I have a directed graph inputted in the following format in Mathematica: g = {{1, "a", 2}, {2, "b", 1}} I'd like to plot this graph using ...
96 views

### Evaluating an ItoProcesss function

The following is my Stochastic D.E.: ...
132 views

### Mathematica regex equvalent of \l

In normal RegEx \l will make the character to the right lowercase. However, it seems like the RegEx in Mathematica does not have this functionality. For example ...
3k views

### Quality of random numbers

Mathematica has several ways of generating random numbers: Congruential, ExtendedCA, Legacy, MersenneTwister, MKL, ParallelGenerator, ParallelMersenneTwister, Rule30CA. For ...
209 views

### Create Slider to start/stop/move Point

I want to be able to start, stop, and move the dynamically moving point simultaneously in both animations. The "PlayPauseButton" in the animations only controls the given animation. Indeed, I want ...
142 views

### Creating a Dynamic MSSQL connection

Hello i am trying to create a notebook that automatically connects to a database on MSSQL server and would then query this to create a sort of personal report. I have connected to this database and ...
142 views

### What is the signature for a callback function for FinancialIndicators?

I'd like to write my own indicators to use with functions like TradingChart. From the context, it's clear that one needs to write a function whose parameters ...
48 views

### Pruning coordinates in subarrays of a list conditional on them having non-real components

If I have a list of 2D coordinates placed in subarrays of a data structure like the following: ...
147 views

### Find $Y \in (0, 5)$ such that the roots of $4x^2 + 4xY + Y + 2 = 0$ are real?

The problem is to find all $Y \in (0, 5)$ such that the roots of $4x^2 + 4xY + Y + 2 = 0$ are real. I took a straightforward approach with Mathematica with the intent of listing the only solutions ...
305 views

### Selecting for 2D points that are within a threshold distance of an upper- and lower-bound number of points

I have a very large set of 2D points: numberOf2DPoints = 10^6; pointList = RandomReal[{0, 1000}, {numberOf2DPoints, 2}]; I'd like to find a way to quickly ...
279 views

### What algorithm and tools should I use to search a data set for the point nearest to a given point?

I have about 1,000,000,000 points, which are the longitudes and latitudes of some places in a city, formatted like this: $(106.1231233,41.43234234)$. I also have about 20,000 points which are the ...
148 views

### Incorrect behaviour of Locator inside Show?

Why doesn't Locator behave correctly in the following code? ...
2k views

### Animate curve parametric plot on a surface

I have a surface s = Plot3D[{x,y,F[x,y]},{x,-1,1},{y,-1,1}] with $F$ predefined, and a curve ...
1k views

### No result from DSolve

I don't get any answer when I evaluate the following expression: ...
195 views

### Finding the characteristic function of a TransformedDistribution[]

I am trying to find the characteristic function of a sum of "named" distributions, though I am interested in how to use Mathematica to find the characteristic function of $$f(X_1,\ldots, X_n),$$ where ...