2
votes
1answer
433 views
11
votes
2answers
541 views

Vlookup function as Excel in Mathematica

How can we create a Vlookup function, similar to what we have in Excel? So if we have a table a and another b, we could add ...
8
votes
3answers
181 views

Using LinkSnooper for monitoring the communication with an installable MathLink program

How can I monitor the communication between an installable MathLink program and the kernel? Can LinkSnooper do this?
1
vote
1answer
180 views

How to transform equation

Is there any possible way to write this equation of 4th order as a system of two diff equations of second order with two new variables and to do that automatically? statespace command is transforming ...
10
votes
3answers
347 views

Sinusoid modelling

There are lots of great demonstrations that show how to get periodic functions in the unit circle. I'm wondering how hard it would be to simulate a "moving grid" similar to this video on youtube ...
4
votes
1answer
419 views
2
votes
0answers
109 views

Programming Mathematica - Introduction by Paul Wellin [duplicate]

Possible Duplicate: Where can I find examples of good Mathematica programming practice? Can anyone recommend a decent book on programming mathematica ? I came across this which looks to be ...
5
votes
1answer
115 views

how to print stack trace when TimeConstrained times out

According to the documentation, TimeConstrained generates an interrupt which interrupts the computation. This interrupt is treated just like an abort, at least in ...
3
votes
1answer
210 views

Determining the partitioning of Do loop iterations between kernels?

Say I have some Do loop that I'd like to evaluate in parallel: Do[Something, {i, 1, M}]. I'd like to split this list up into ...
0
votes
1answer
232 views

How to write case, in piecewise function, correctly [closed]

I want to plot graph of this piecewise function in Methematica: $f: [0, 1] \mapsto \mathbb{R} $ $f(x)= \begin{cases} \frac{1}{x - \frac{1}{3} } & \text{ if } x \in [0, \frac{1}{3}> \newline ...
4
votes
3answers
660 views

BoxWhiskerPlot - how to specify boxes position on the horizontal axis

Let's say I have a folowing set of data: k = 1 : list of values k = 3 : list of values k = 10 : list of values I know that to make a BoxWhiskerChart I have to ...
0
votes
1answer
144 views

simplification rule with symmetry

What rule can you think of to replace the first line by the second? I have a bunch of expression like these, which I would like to simplify. All dependent cross terms must be written in the same ...
3
votes
1answer
542 views

Combinatorica vs Built-in functions: Use of MinimumSpanningTree

What kind of argument is expected by MinimumSpanningTree (from the package Combinatorica`)? Is it possible that I am providing ...
6
votes
3answers
360 views

How can I rewrite this with NestList or FoldList?

The original code used For: ...
35
votes
3answers
882 views

Applying TextRecognize on alpha-numerical table

From time to time I have to extract data from scanned papers or rasterized PDFs. Imagine a table of the following kind (but much longer): A naive application of ...
3
votes
2answers
480 views

Ways to plot interpolating functions more economically?

I am interpolating a lot of data over geographic coordinates obtained via GPS, and frequently I need to plot these interpolated functions together. For example, I may have an interpolated elevation ...
21
votes
2answers
308 views

Evaluation of OptionValue[]

I have a function that takes an OptionsPattern and I want to access several options, say a, and ...
6
votes
1answer
180 views

Estimate Imagesize of any given Particular Control object?

I make different controls(InputFields,Text,panel, etc) in my code for which the corresponding code is below. ...
1
vote
1answer
132 views

Understanding a slowdown associated with wrapping a set of nested Do loops with a ParallelDo expression

I have a set of set of nested Do loops that require data from three different arrays (though the position from each array is fixed per cycle of the outer Do loop). Let's call these arrays: ListA, ...
5
votes
1answer
408 views

symbolic integration of a definite integral, how to speed up

I am wondering what are the general tips & hints for speeding up symbolic integration. As far as I understand, it solely depends on the form a function is represented before it is processed by ...
3
votes
1answer
139 views

Efficiently finding the maximum value of a column in a matrix

Imagine I have a matrix of the following form: TestArray = $((a_1,b_1,...),(a_2,b_2,...),(a_3,b_3,...),...)$, where a specific example might be: TestArray = ...
3
votes
0answers
52 views

How to influence Suggestion Bar in your package/code [duplicate]

Possible Duplicate: Is it possible to customize the Suggestions Bar? I have written a little code (like a minipackage) of different functions. In using my code, the user typically starts ...
5
votes
3answers
3k views

How can I transpose x and y axis on a Plot?

This question has appeared in various forms online, but I have not yet seen a complete answer, so I am posting it here. More specifically, suppose I have a function ...
3
votes
1answer
251 views

install mathematica 9 on linux encounter “Glibc_2.4” not found

I tried install mathematica 9 on linux. The whole process is fine. After the installation. I type "mathematica", and came up following lines: ...
5
votes
2answers
243 views

How can I make the output from Solve look nice?

I have a problem with presenting solutions. Roots of 4th order polynomials are big expressions. Is there a way to present the roots, s2 and s3, in normal form with some substitutions? Maybe a way to ...
2
votes
1answer
148 views

writing a function using multiple variables

I am fairly new to Mathematica and am trying to write a function for the equation: xx = [x/(Sqrt[h^2 + d^2 + y^2]))*(Sqrt[h^2 + (d + yy)^2]) where h, d are known ...
15
votes
5answers
942 views

How to check if an expression is a real-valued number

What is a simple, fast way to test whether an expression is a real-valued number? I ask since there is no RealQ function. If we call this test ...
5
votes
2answers
296 views

Make contour lines level with graph interval?

I am graphing the voltage traveling through some water with two electrodes. I have the graph with contour lines and all, but is there any way that I can get the contour lines to be at the tick marks ...
2
votes
2answers
298 views

Packages problems on version 9 under OS X

Using Version 9 on OS X, I've run into some problems with creating packages and accessing them. I've done the following: wrote all the function definitions in a notebook and tested that they all ...
3
votes
0answers
109 views

How can I truncate only a single vertex of a polygon?

One can truncate all the vertices of a polygon at once with Truncate. I want to do exactly that -- but only on a single vertex. Is this possible with Mathematica 9? ...
2
votes
1answer
98 views

Parallel computing NInverseFourierTransForm

I am running the code below, and it works perfectly. I have some function in Fourier space, and I take the numerical InverseFourierTransform. However, I will have ...
2
votes
1answer
434 views

Mathematica Mac Keyboard Shortcuts not Working?

Really I'm just trying to use the Ctrl+2 shortcut to make a radical, but for some reason this won't work. What could possibly be going wrong? The exponent shortcut works (i.e. Ctrl+6).
2
votes
1answer
187 views

A Sierpinski-ish structure, via 2D automata

The project is originally based on a puzzle proposed by EIORU at http://www.ptt.cc/bbs/puzzle/M.1342451949.A.00F.html (若您懂得讀中文 / if anyone happen to read Chinese^^) last July. The descriptions, ...
5
votes
1answer
729 views

Monte Carlo simulation using geometric Brownian motion

I'm relatively new to Mathematica programming, so forgive my rather unsophisticated question: I'm trying to do a Monte Carlo simulation using geometric Brownian motion (GBM). I want to write a ...
2
votes
0answers
359 views

mathematica startup time

I have Mathematica 7 and 8 installed on my laptop. Mathematica 7 starts quite fast, but Mathematica 8 is extremely slow to start. In the Option Inspector I canceled the "welcome screen" option at ...
5
votes
3answers
519 views

Avoiding grid lines inside filled area in RegionPlot exported as PDF

Basically the same question as here, but now with regions which have opacity. ...
5
votes
0answers
337 views

Modeling neural excitation with a non-linear differential equation

I think I have a special problem and I am not sure how to search for an answer, so I thought I would try here. I am working with the so called FitzHugh-Nagumo model which describes very simple ...
8
votes
3answers
314 views

DataEncoding and compression in HDF5 format

I would like to export data in HDF5 format with Mathematica 9. The Mathematica manual about Import and Export of this format can be read here. As I'm dealing with large arrays, export often lead to ...
3
votes
2answers
201 views

Handling error in database connection (TimeConstrained)

I have a lot of scripts that use a database connection, and I have realized that my code should be protected against errors in my connection. For example, when my database is out for some technical ...
5
votes
5answers
1k views
5
votes
1answer
116 views

Syntax highlighting in patterns with built-in functions

While working on my own plotLegends package I encoutered some weird behaviour of the front end's syntax highlighting. I reduced the problem to the following minimal ...
0
votes
1answer
196 views

Frequency of elements in a list

I've got a list in the format of list={{a,1},{a,1},{b,1},{c,1},{b,1}} And I want it to "compress" into a list of pairs ...
0
votes
3answers
314 views

Removing -> from list of numbers [duplicate]

Possible Duplicate: Best way to extract values from a list of rules? If I have a vector v = {x->1.03, x-> 2.01, .... }, and I want to use an element in the list, I can get an element as ...
9
votes
3answers
5k views

Finding unit tangent, normal, and binormal vectors for a given r(t)

For my Calc III class, I need to find $T(t), N(t)$, and $B(t)$ for $t=1, 2$, and $-1$, given $r(t)=\{t,t^2,t^3\}$. I've got Mathematica, but I've never used it before and I'm not sure how to coerce ...
0
votes
1answer
170 views

Creating Recursive Sequences

Quite a simple question, I reckon, however, even quite an extensive search hasn't helped me. I want to define a recursively defined sequence that starts with defined ...
1
vote
1answer
178 views

Finding parameters for first positive root of solution to differential equation to be equal to a desired value

I have a differential equation with parameters. The objective is to vary the parameters such that the first positive root of the solution is equal to a desired value ...
5
votes
1answer
124 views

Throwing away all expression on a loopback link

What is the simplest way to throw away all expressions waiting to be read on a loopback link, effectively resetting the link? I am building an expression on a loopback link using the C MathLink ...
4
votes
1answer
167 views

Feedback on my Subscript code

I have written a code, and I need a little feed back.. I want to make the Subscript distributive across (1) addition and (2) multiplication to mimic short-hand for ...
0
votes
1answer
470 views

Asymptotic expansion, negative powers

The question was inspired by this discussion: How to expand a function into a power series with negative powers? I am interested in asymptotic behavior of a function at infinity: ...
5
votes
1answer
450 views

Volumetric analysis from topological maps

I want to calculate the volume of fill required to level an area about the size of three foodball fields. The Department of Public Works in my city can provide me with topo data for the area. Their ...

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