5
votes
2answers
483 views

Exporting row vector as a column in excel

I want to export a vector in Mathematica to appear as a column in Excel. I am trying A={1, 2, 3}; Export["mfile.xls", {"A" -> A}] But it is showing 1,2,3 in ...
1
vote
1answer
208 views
10
votes
0answers
715 views

Dataset in Mathematica 10.0.1

Wolfram pages "Mathematica Quick Revision History" in Mathematica 10.0.1 release says: "New operators and compositions of operators enabled for associations functions such as Dataset and Query" ...
3
votes
0answers
100 views

Is there a way to convert the mathematica document into word document in a neat way?

Is there a way to convert the mathematica document into word document in a neat way? I tried by "save as" command and found something like Risk text format "*.rtf" but still many parts look messy.. ...
4
votes
2answers
173 views

Display Quantity in full form

Is there a way to display Quantity[] in full form in the output? I know you could use Quantity[valuse, Unit]//InputForm, but ...
1
vote
1answer
72 views

Why does my Dynamic NonliearModelFit keep running?

I have complex data and which I am fitting to a complex formula. In order to use NonlinearModelFit I split the formula and the data into real and imaginary parts. ...
2
votes
1answer
197 views

Double integral changing the limits

This integral does not evaluate: Integrate[ Integrate[1/(E^((a - c)^2 + (b - c)^2) ), {c, 0, 1}], {b, -Infinity, Infinity}] However, reversing the integrals ...
5
votes
1answer
160 views

Building an arch in SystemModeler

I'm trying to learn SystemModeler and struggling a little... Building on the chain pendulum example from Wolfram, I've happily made a chain with revolute joints with spring/dampeners connecting the ...
4
votes
1answer
90 views

How to set the width of grid elements in pixels?

That is all: How can I set the width of columns in a Grid in terms of pixels instead of 'ems'? To be more precisely, I want to create a grid that is 330 pixels ...
7
votes
2answers
390 views

Display variable name instead of value

Is there a way to display the variable name instead of its value? for example, I need something likevarname = 1; function[varname]; and the output is ...
2
votes
1answer
197 views

Variable number of controls in manipulate

i want to add a variable amount of variables to manipulate, but i got stuck at one point and can't figure out a solution (even after reading here for hours...). I have a function (e.g. here a ...
9
votes
4answers
260 views

Conditional ListPlot with text recognition

This is my data ...
2
votes
2answers
204 views

How to get the series coefficient of a function defined by a differential equation [duplicate]

I need a Taylor series approximation for $x(t)$, which is defined by the following differential equation. $\frac{dx}{dt}=-k_1 x+(1-x)k_2 e^{-k_3 t}$, $x(0)=0$ ...
2
votes
1answer
75 views

How to overwrite a private symbol value temporarily?

I have a package file mypackage.m with BeginPackage["Foo`Bar`"] Begin["`Private`"] tmp=2; foo=2*tmp; myprogram[foo] ... End[] EndPackage[] The file is VCS ...
7
votes
1answer
862 views

Plotting a moving ball for projectile motion with animate

Here is my code for plotting an orbit. What I want to do is have the "planet" shown as it orbits in the simulation. Can anyone help with this? ...
5
votes
3answers
930 views

Finding exponential model from data [duplicate]

I'm trying to find an exponential model from data for a homework problem. There is an accompanying video explaining how to do the bigger problem but it omits any instructions on the step where the ...
11
votes
5answers
533 views

Applying a function to a Dataset column conditional on another slot's value

How to apply a function to a column conditional on another slot's value? The Dataset documentation show only how to apply a function to named slots independently. The ...
8
votes
1answer
131 views

Auto highlighting input cells depending on input expression (eg its Head)

Is it possible to programmatically highlight (eg, by change background color) an input cell conditional on the input expression's Head (or other attributes) upon evaluation? For example, would like ...
1
vote
3answers
243 views

Can I find constants in a function?

Let's say, I have a function with a constant, e.g. $y(x)=x+c$, and a condition $y(0) = 5$. I want to type in something like Solve[{y[x]=x+c, y[0] =5}, {c}] and get ...
0
votes
1answer
264 views

How can I resolve the insufficient memory to complete the computation problem for solving function with iterated variables?

I am trying to solve for a value x in a function where the variables varies with iterations of K. Also, there is one variable called "rvsum" which is updated with a certain formula as well. I have ...
3
votes
0answers
117 views

Why is it not allowed to define vectors of variables in a scoping construct?

The following command assigns 1 to a, 2 to b and 3 to c: ...
2
votes
1answer
236 views

Import selective elements from mixed (text and numbers) data file

How can I import only the 2nd and 5th elements (numbers, located in the 2nd and 5th columns) from all n raws of a data file (.xlxx) that contains both numbers and text. Imported data be inserted into ...
4
votes
3answers
302 views

have a function redefine itself as it maps through a list

I have a list which contains sublists, e.g. list = {{a,b}, {a,b,c}, {a,b,a,a}, {b,c}, ...} I then map a function through each sublist. This function should ...
3
votes
4answers
549 views

drawing core-shell structure [duplicate]

I am pretty new in Mathematica drawing. I am trying to draw a core-shell structure, it means a core sphere with a shell sphere, like this It can be in 2D or preferentially in 3D. Does someone can ...
1
vote
0answers
47 views

How to call a java method that takes a boolean (not Boolean)?

I'm trying to call a method on a java object that takes a single boolean argument - note boolean (native or primative) not Boolean (Object or Reference type). ...
2
votes
1answer
166 views

Select in complex dataset query

I want to use Select for a more complex dataset query. Part of the query shall be dynamic, depending on the user input. The Select part looks something like ...
1
vote
1answer
104 views

How to understand the extensional usage of Flatten? [duplicate]

Recently, I have been reading Mathematica program that written by many advanced Mathematica user, like Mr.Wizard, J.M., Kuba,etc to improve my programming capacity In the On generalizing Partition[] ...
4
votes
3answers
840 views

Find arc length

I am trying to find the arc length for using ...
21
votes
0answers
252 views

What is ColorEqualSigns and how does one use it?

I'm setting up the SyntaxInformation for a package I'm writing and I'm struggling to understand what the "ColorEqualSigns" ...
0
votes
3answers
642 views

Is there a way to rewrite integrals in Mathematica using u substitution?

In Mathematica, can I give it an integral and a few substitution rules and have it rewrite the integral in terms of those variables?
0
votes
2answers
130 views

Replace $z$ with interpolated function and plotting

I start off with this equation $z(x,y) = sin(xy)$. I create an interpolation from $0 < x < 5$ and $0 < y < 5$. I then use this interpolation on a simple function $w(x,y) = x + y + z(x,y)$ ...
9
votes
5answers
719 views

Coalition Games

Suppose an election produces the following result: result = {{"a", 120}, {"b", 80}, {"c", 50}, {"d", 30}}; Letters are parties and numbers seats. To form a ...
3
votes
2answers
265 views

How to propel the integration of time a little bit further? Numerical solution can not evolve to the max time

I try to solve a nonlinear partial differential equation. I obtain a numerical solution which can not continue to the max time I set, I always receive message NDSolve::ndcf: Repeated convergence ...
2
votes
2answers
403 views

How to specify units for ImageSize Option? [duplicate]

I'm trying out making a CDF and I want it to print within the margins of Letter paper. There is an ImageSize option that I would like to set; some plots will be in ...
2
votes
1answer
230 views

Coupled Nonlinear Differential Equations Problem

I have a big problem solving a set of coupled nonlinear differential equations using NDSolve. Solving the equations by themselves works quite well but if I want ...
15
votes
3answers
520 views

How to manipulate a circle in GeoGebra style?

I want to emulate the GeoGebra app. I want to get an effect like this in Mathematica. I don't know how to move whole circle without changing the radius of the circle. My sample code: ...
5
votes
1answer
147 views

Mapping over an association producing an unexpected result

The documentation for associations says that the keys of an association are transparent for many operations. Map is one such operation. However, I am confronted ...
2
votes
1answer
164 views

Changing the length of the vectors in vectorplot [duplicate]

I have the following code, and I've tried almost everything I can think of, even VectorColorFunction to describe magnitude. I am trying to make the length of the vectors proportional to r^{-2}, and ...
4
votes
1answer
151 views

How do I bandpass a signal in Mathematica 8

I would like to use the bandpassing function that is available in newer versions of Mathematica but not Mathematica 8: ...
3
votes
1answer
286 views

Second order differential equation

Hey guys I need someone to give me a hand on this. I don't know if this is too complicated or it's just the lack of knowledge I have on Mathematica. I'm trying to solve the following equation but ...
10
votes
3answers
462 views

Maximize violating constraints

I have Maximize[{(h*10)/(300*(100 - (l^.5 + d^.4 + H^.6))), (l + d + H + h) == 669, l > 0, d > 0, H > 0, h > 0}, {h, l, d, H}] I believe ...
10
votes
3answers
387 views

Wrong answer from DSolve?

I was trying to solve the initial value problem $$u'(t) = \sqrt{u(t)} + \frac{1}{n+1}, \, u(0) = 0$$ using DSolve: ...
7
votes
2answers
208 views

Solving with DSolve recursively

I need to find $f(x,n)$ in the interval [0,1] defined by recursion, \begin{equation} \frac{d f(x,n+1)}{dx} = f(x,n) \end{equation} with boundary conditions $f(0,n+1) = 1$ and $f(x,0)=1+ x $ Using ...
2
votes
1answer
206 views

ListContourPlot is blank

This is probably very simple. I want to do a simple ListContourPlot. ...
12
votes
7answers
704 views

Splitting strings into letter keys and integers

I have strings of the following form: string = "ABC123DEFG456HI89UZXX1"; Letter keys of variable lengths are followed by (positive) integers. I want to get this ...
8
votes
3answers
312 views

Efficient method to generate Tridiagonal 50 by 50 Matrix? [duplicate]

I'm looking to generate a tridiagonal 50x50 matrix, ideally without using loops. Suggestions on most efficient code for this?
7
votes
1answer
252 views

Incorrect result while using SemanticImport for CSV file import

I might use this incorrectly. I want to use a .csv file that (as list) looks like: ...
5
votes
3answers
1k views

Generating random symmetric matrix

Suppose first that I want to generate a matrix whose elements are independent and identically distributed (i.i.d.) with distribution dist. This is easy: ...
10
votes
1answer
227 views

Why can't a string be formed by head String?

Since everything is an expression in Mathematica, why must a string object be formed by "abc" but not by a String[abc] ...
5
votes
1answer
117 views

Determining the range of parameters that yield real values for a certain NIntegrate form

I have specified just one set of $s$ and $g$ values that yields a real value for the NIntegrate below. It is possible that some $s,g$ combination can give rise to ...

15 30 50 per page