# All Questions

139 views

### TabView switches tab number without user input in first evaluation

I've attempted to use TabView in a Manipulate to display sets of controls and alter a "display" associated with each set of ...
284 views

### Exporting tables of interpolating functions

A few weeks ago I asked a question about manipulating parameters in NDSolve (Looping with NDSolve?) , and received some very helpful advice about the manipulate environment; now I want to take the ...
73 views

### Preventing numeric constants from being pulled out of square roots

If I input Sqrt[2 g], Mathematica automatically pulls out the 2 and returns Sqrt[2] Sqrt[g]. ...
541 views

### How to get rid of all complex numbers and functions?

For almost esthetical reasons, I always have been fascinated by infinite sums of series and I always wonder if theyhave a closed form. A couple of days ago, I found on MSE a question related to the ...
284 views

### Multiple NIntegrate (again)

Basically I have the same question as here: Multiple NIntegrate but since I don't have enough "reputation" I cannot comment there. I want to solve the following multiple Integral numerically at given ...
281 views

### Conditional Check on Matrix

Suppose I have the following matrix (i,j): ...
119 views

### Back Linear Substitution

I have an equation set Ax=b and A(n*m),n<m . To lower down the dimension, I express some vars by other vars, which gives ...
1k views

### Line of best fit on LogLog plot

I have a LogLog plot, and i'm unsure about how to fit a line to it. The data represents a calibration curve. ...
250 views

### Changing Plot order for 3D printing

Alright, I got a my first 3D print done of a pseudosphere using parametric plot and a deflated sphere using a contour plot, but when I try ...
248 views

### Fundamental Theorem of Calculus for definite integrals… assume continuity?

So here's the problem: I can evaluate the indefinite integral: Integrate[D[u[x], x], x] u[x] However, I'd like to ...
290 views

### Performance regression for Fold?

Bug introduced in 8.0 and persisting through 10.1.0 or later I noticed an over 10x performance drop on Mathematica v9.0.1 (as Oleksandr R. commented, also v8) compared with v7.01 for this code: ...
466 views

### Convert number to exponent form with highest power possible

As a school assignment we have to write a program which solves this issue. Since the program has to run efficient I am wondering what the best way is to approach this issue. Of course there you can ...
31 views

### Use Map with OptionValue [duplicate]

Trying to map OptionValue to a list of option names doesn't work. ...
22 views

### Manipulating named patterns inside replacement rules [duplicate]

When I evaluate the following expression, {a -> "value1", b -> "value22"} /. {Rule[x_, y_] -> Rule[x, y]} I get ...
180 views

### What are the differences between library call back functions and WolframCompileLibrary macros?

I'm trying to use LibraryLink in Mathematica, and come across some problems. Consider if we have a MTensor m1 which contains a one dimensional double array, and I ...
120 views

### Establish connection with RLink and Rtools

Has anyone gotten RLink to work with Rtools (or even tried)? If so a simple step-by-step would be much appreciated ! When attempting to access any Rtools functionality through RLink I get: The ...
103 views

### How to extract a variable names (not values) from a list of transformation rules?

I am trying to extract variable names from a list of transformation rules mapping = {var1 -> 'val1', var2 -> 'val2' }. Variables ...
254 views

### How to do Inverse formulas/Rearrange formulas in Mathematica? [duplicate]

Hi am a student in chemical engineering and I have the necessity to rearrange formulas algebraically, for example ...
158 views

### Maximum of NDSolve output. Problem with interpolating function

I solve a NonLinear PDE and get a solution (which for other reasons I put into a vector): SolVec1[1][[2]][x,t], where x and t are the indipendent variables. Now, I would like to get a distribution ...
670 views

### Why does Mathematica evaluate Sin[2.0] but not Sin[2]?

I can't understand why is it that In[88]:= Sin[2] Out[88]= Sin[2] while In[89]:= Sin[2.0] Out[89]= 0.909297 I even tried ...
792 views

### Plot Fourier transform of $\sin (2 t)$

I'm trying to plot the Fourier transform of $\sin (2 t)$. I tried using the FourierTransform Function (I'm expecting a peak at w = 2) but it gives me undefined at ...
783 views

### Quickly calculating the mean / median of a function over an interval

I'd like to calculate the Mean or Median value of a function over some interval $[a,b]$. However, I can't seem to find how to do this in help. Specifically I'd like to have something that works like ...
334 views

### Using NDSolve for three variables as function of time

I want to be able to plot z, and r. Should I be using DSolve, NDSolve or something else? I've tried to clear it up a bit Thanks, Will ...
155 views

### How to change the format of FrameTicks

Here is a plot with the default frame ticks S1 = Plot[Sin[x], {x, -7, 7}, Frame -> True, Axes -> False] Now, if I define myself the range as well as the ...
380 views

### Solving Rotational Equations of Motion

I'm trying to integrate the rotational equations of motion ...
101 views

### How can I check if one expression implies another?

Say I have one expression, for example $x^3-3 + c = y$, and I want to check if it implies another with some set of explicitly stated assumptions. With the previous example, assuming all variables are ...
73 views

### LinearProgramming behavior

Consider the following linear programming problem: ...
495 views

### Multiple curves plotted with different colours [duplicate]

I am trying to use ColorFunction for 2 functions on the same plot. I only want the cubic equation to change colour. ...
126 views

### Define customised distribution with discontinuous CDF

I have the following CDF: ...
36 views

### How do I define a tensor from another tensor with summations? [duplicate]

Let's say we have a rank 2 tensor $g_{ij}$. This is basically a list with a Depth of 2. Now I'd like to calculate another tensor ...
267 views

### Is there any Robotic Package in Mathematica?

Is there any Package in Mathematica that deals with Robotics and their application?
3k views

### How to find integer solutions?

Following is the equation: Need to solve for integer values of x,y when a,b lies between -1000 and 1000. Problem is to find the number of integer values of pair (x,y) that satisfy it.
408 views

### Finding connected components in an array

I have an $w\times h$ array with non-negative integers. I wish to partition the set of coordinates $(c,r)$ with $1\leq c \leq w$ and $1\leq r \leq h$, in subsets, so that each subset corresponds to a ...
262 views

### Variable scoping in Module

I don't understand why $a$ and $b$ are not local in the following code: ...
143 views

122 views

### Testing for arbitrary algebraic expression in given variable

I want to test, for example with MatchQ, if the argument of a function is an arbitrary expression in a single or several variables whose names can be assumed to be ...
281 views

### Boundary condition is not specified on a single edge of the boundary of the domain

I am attempting to solve a PDE as prescribed in a paper I am reading; however, Mathematica doesn't seem to be happy with the way I am posing the problem. Im my case, r(t,100) is an approximation of ...
107 views

### Problem with ViewVector

I am trying to have a satellite (camera) move around the earth (unit sphere) and take picture of the earth. The satellite keeps constant distance from the earth, and always looks toward earth center. ...
82 views

### Problem with files size

I need to work with long time series, but I notice that this generates huge files that Mathematica doesn't handle well at all: even opening/saving one of this files is difficult, and the kernel quits ...
75 views

### Excluding an interval of parameters from Integrate [duplicate]

I'd like to compute an integral that depends on a parameter, but I'd like to exclude an interval from the computation. For concreteness, say I want to compute ...