1
vote
1answer
395 views

Solve equation with inequalities for parameters

I want to solve following equation: ...
2
votes
2answers
327 views

How to draw Graphics3D items with straight border lines?

I want to make a Polygon with straight border lines. For that purpose I wrote the following code, but it doesn't show straight borders. ...
0
votes
1answer
151 views

Problem with plot of discontinuous function of 2 variables and adding legend to a contourplot

I have 2 problems with which I would need help: -first one is that I would like to plot a discontinuous function of 2 variables but can't succeed (see attachment) -then I also would like to display ...
0
votes
1answer
148 views

TabView resets to default when selecting data using Control object

I have 3 drop down boxes on one of the tabs in my TabView. Two of the drop down boxes results are used in a Select statement to ...
1
vote
1answer
84 views

Why doesn't Compile work on Permutations function with second args?

Here is a narrowed-down example, the first case works, but the second one refuses to use the compiled version: ...
2
votes
1answer
946 views

How to solve equations self-consistently

I want to solve the following equation self-consistently. So, H.u = e.u {{1, d}, {d, 1}}.{u1, u2} = e.{u1, u2} I guess an initial value for ...
4
votes
1answer
106 views

How to substitute $x$ in a expression $f(x)$ but not calculate the value of the $f(x)$ at the point $x$?

I want to subtitute $x = 1$ into the expression $$f(x)=x^2 + 3 (x^2 - m^2) + \sqrt{x^2 + 1}$$ but I don't calculate the value $f(1)$, that is mean, I want $$1^2 + 3(1^2-m^2)+\sqrt{1^2 + 1}.$$ If I ...
0
votes
1answer
2k views

How can I get the solution of complicated implicit function?

The question is what is the method to solve the implicit function has real and imaginary number. For example, The function is $$F(x,y)=(-I*x + 2*y^2)^2 + x^2 - 4*y^4*Sqrt[1 - I*x/(y^2)]$$ Although ...
10
votes
2answers
2k views

How to use “Drop” function to drop matrix' rows and columns in an arbitrary way?

The built-in function "Drop" can delete a Matrix's row and column. Typical syntax for "Drop" is as follows: Drop[list,seq1,seq2...] But what if I want to drop a ...
4
votes
1answer
352 views

A Graphics`Mesh`ConvexHull[] peculiarity

I have been unable to explain the behavior of Graphics`Mesh`ConvexHull[] on the following (highly simplified) example: ...
10
votes
1answer
726 views

How do I generate the Mathematica Version 2 Spikey in Mathematica?

As we all know, Mathematica changes its logo design with every new version, while still maintaining the dodecahedral/icosahedral motif. I have been able, through much digging around, to finally ...
3
votes
2answers
852 views

How to color lines in Epilog

I often use Epilog to label lines within graphs, and I like to coordinate the color of the labels with the color of the lines they're labeling. This is no problem. However, I'm currently working on a ...
0
votes
1answer
229 views

Evaluating derivatives for use in solve

I need to evaluate the derivative of a function. My function looks like approx[vector_, x_] := Sum[vector[[n]]*Basis[n - 1, x], {n, 1, Length[vector]}] and I'm ...
2
votes
1answer
216 views

Using transformation rules to manipulate expressions

I'm trying out Mathematica as a replacement for LaTeX for typesetting math. It works very well, but I would like to take advantage of Mathematica's computer algebra capabilities as well. Specifically, ...
0
votes
1answer
265 views

Integrate function without specifying limits of integration

I've been having trouble to make mathematica evaluate an integral without specifying the values of the limits of integration. I mean, if I write ...
0
votes
1answer
114 views

Mathematica not simplifing when using FullSimplify

I am trying to simplify the following $(Z_i - Z_{i+1})^4$ using ...
4
votes
1answer
128 views

Unexpected result when reading Cell with comment-lines by NotebookRead

When considering this question about re-formatting Cell (also this one), I encountered an issue which confuses me. I'll let the code itself speak: Consider the ...
10
votes
3answers
343 views

“Stacked” BarChart with BarOrigin $\to$ Top makes y-tick marks negative

This bug was fixed in version 10.0.0 When BarChart layout is "Stacked", setting ...
3
votes
3answers
809 views

Solve with v9 (issues with Subscript, Overscript, Superscript etc)

The way Solve works has changed in v9 ... in essence, to get the answers that one obtained under v8, one now often has to specify a lot more information about all ...
6
votes
2answers
460 views

CorrelationFunction for vectors

Mathematica 9 has a new CorrelationFunction. Sadly the joy does not last long, as I can't get it to work with vectors. I would like to make a velocity correlation ...
3
votes
1answer
147 views

Downvalues vs. Scoping for Functions

Regarding my recent question on using a default value for a function argument when a pattern was not met yielded some interesting answers, but the general consensus was "Yes this can be done, but ...
3
votes
2answers
362 views

Extracting a single layer from a SHP file

I have an ESRI ShapeFile (SHP) that I've loaded. It has a number of layers which I can see the names of by using: Import["file.shp", "LayerNames"] I get ...
5
votes
2answers
213 views

How do I remove the subscript after calling BaseForm[]?

Say I want to convert some number $N$ to base $k$. Here, I might use the command BaseForm[N,k], e.g.,BaseForm[10,...
18
votes
1answer
5k views

How to remove redundant {} from a nested list of lists?

There are numerous examples here, whose end result is the removal of empty brackets {} and empty lists. I still can't find an example of simply removing redundant ...
2
votes
2answers
182 views

How to change the last plotstyle of a list

I'm using ListLinePlot to plot a list containing 10 lists, using the default colors: ListLinePlot[myList] I would like to be able to keep the default PlotStyle ...
1
vote
3answers
206 views

Separate an array in two arrays, the even and odd terms being separated in these two arrays

How can I separate the odd terms in one array and the even terms in another array,i.e., go from a={1,2,3,4} to aeven={2,4} ...
-4
votes
3answers
240 views

How can I draw this plot?

How can I draw a plot like this one? I want to be able to specify the x-axis, y-axis, and z-axis ticks and the number of bars in the plot.
8
votes
1answer
175 views

Converting to InputForm or StandardForm without deleting comments

Following on from this question: Is it possible to convert an expression to InputForm or StandardForm without losing the comments? For example, ...
0
votes
2answers
2k views

How can I make a transparent 3D Rectangle?

Sorry, I didn't mentioned clearly in my earlier post. I want to build a transparent Rectangle, within which I want to diffuse a certain color of my choice which is ...
2
votes
1answer
154 views

Mathematica 9.0 problem: ParallelTable with SQLExecute

I have run into the following problem: when I try to run the following code in Mathematica 9 I get SQL connection error on all kernels. The code is: ...
1
vote
0answers
120 views

Better alternatives for the Sound function?

The Sound function represents the sound signal very primitive in my opinion. There are only two buttons (play and pause). No rewind, no playing from some point on (like the most sound players have). ...
5
votes
1answer
325 views

Proper use of arbitrary number of variables

So, I'm working on a project where the number of independent variables is not fixed. Consider a problem of $N$ independent variables, $\boldsymbol{r}$. I want to perform different things with them. ...
1
vote
2answers
207 views

Subtract more than one array using DeleteCases

I need to create an array subtracting two arrays from another array. I know how to subtract one: am = DeleteCases[amp, Alternatives @@ af] I can subtract an ...
0
votes
1answer
73 views

How to get a number, but not a list, of the dimension of your array?

I need to use the dimension of a certain array, to use it as a bounder in a loop afterwards. The problem is that I get a list, when write : ...
-2
votes
1answer
328 views

Non-regular grid data

I have issue with non-regulary spaced data. I have set of 3 numbers {x, y, z} in my list. ...
4
votes
1answer
159 views

How can I write image to MySQL database?

I have a database, such as: In Mathematica, the final code is: img1=Export["/home/user/Desktop/1.jpg",resultimg1]; I tried ...
4
votes
2answers
201 views

Updating the format style of input cells from an older/'pre-styled' notebook

I have been given a large notebook that was created in mathematica 6. It contains a structure of sections and subsections and the input text is formatted in an unusual (possibly just old) style (see ...
2
votes
1answer
1k views

Executing a .m file from the Linux command line

I have some code in a file named Demo-3.m, It can be evaluated in Mathematica 9. The final expression in the file is ...
0
votes
0answers
86 views

NIntegrate, view integration options [duplicate]

The Mathematica manual says: NIntegrate symbolically analyzes its input to transform oscillatory and other integrands, subdivide piecewise functions, and select ...
5
votes
2answers
309 views

Histogram3D using sums instead of counts

I'm trying to create a 3d histogram/ matrix plot pair. My data is in the form {{TTR1,TBF1},{TTR2,TBF2},....} What I would like is to modify the Histogram3D so ...
2
votes
3answers
343 views

Plotting many tables in a single plot

I have several lists. ...
-8
votes
2answers
530 views

Color plot markers using If statement

I am calculating eigenvlaues. Some are negative, some are positive. I define the index nn and mm (as well as np and mp) of each matrix element by some functions that assign positive, zero and negative ...
1
vote
3answers
1k views

Loop through a list and select elements

I am new to Mathematica and I have no idea how to make a basic for loop work. I want to loop through the elements of a list: Range[45, 200]. I want to select the ...
6
votes
3answers
197 views

How to make a plot of function over 24 orders of magnitude?

Assume these parameter definitions first: ...
2
votes
0answers
255 views

Listing over multiple inputs (tensor rank > 1) in a compiled function

I'm trying to optimize the solution given by Michael E2 to my previous problem (Efficiently determining if 3D points are within a surface composed of polygons) which I figured would be relatively ...
10
votes
7answers
741 views

How to dynamically toggle curves on/off in a crowded Plot?

When multiple curves appear in a single plot, it is useful to interactively turn certain curves on or off to visually compare smaller numbers of curves. It is trivial to put a quick dynamic together, ...
5
votes
1answer
566 views

Include a CDF file in sites.google

I have a website on sites.google and I also have blog on wordpress. I would like to include some CDF files on them. How can it be done?
3
votes
2answers
204 views

The same value of VertexSize for vertices in different graphs causes different vertices size

I generated some graphs. The smallest vertices in the 1st graph should be the same size as the smallest vertices in the second graph. The smallest vertices have the same size (...
6
votes
1answer
1k views

Properly Force Mathematica to Simplify Log Expressions/Rules

I want to be able to expand $\log(x^n e^x) = n \log(x) +x$: FullSimplify[Log[x^n Exp[x]], x > 0 && Element[n, Integers] && n > 1] yields ...
22
votes
4answers
3k views

Efficiently determining if 3D points are within a surface composed of polygons

This is the 2nd part of a previous question which I edited to make into 2 separate questions: Extracting polygons from 3D contour plot surface As an extension of my earlier question involving simple ...

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