# All Questions

175 views

### Clicking phase plane with mouse

Here is what I have thus far: ...
136 views

### How to get output in a specified format

In Fortran, we can easily get the stardard and easy output format. Now, we only focus on the Integer output. See here How to realize this kind of output as formatted text file using Mathematica ? ...
226 views

### How to find out where an error occurs?

I got this error when using Mathematica: ...
168 views

### Solving for the limits of an integral

I am trying to get Mathematica to solve for the symmetric limits of an integral of a Square Wave. ...
122 views

### Only one root at specific interval

I need a help to find k here: $f(x)=-k^x + x^2$ It is not too simple. I have interest to find the single value of "k" where, inside interval {x,2,3}, the function have only one value to x when f(x) ...
78 views

### QuantityVariable usage

When I try to run the following code, Mathematica gives me an error message: "Solve was unable to determine the units of quantities that appear in the input." ...
160 views

### Export collection of plots to A4 pdf

Sometimes I want to Export a collection of plots or other Graphics to a pdf in A4 format. Right now I'm using a GraphicsGrid inside a panel which is an inset in a Graphics object. Here is an example: ...
82 views

### Delete data were y = “NS” in a list with elements {x, y} [duplicate]

I have a list of data {x, y}and not all of them have actual values. They show as {x, "NS"} or ...
419 views

### Mathematica doesn't read .mat file

Bug introduced in 6.0 and fixed in 10.2 (July 29, 2015) To be honest, I don't know if the problem is with Mathematica, or with the file; it's been generated by PicoScope, a PC-based oscilloscope ...
637 views

### Flatten nested lists

I have a list as follows lis= {a, {{{b}, {c,d,e}}, {{f}, {g,h,i}}}} which I would like to flatten to ...
105 views

### Plot Bivariate Data with Marginals

I would like to plot bivariate data along with the marginal distributions. I've arranged the plots in a GraphicsGrid as below but the marginals are centered away from the bivariate plot and I wonder ...
94 views

### Misunderstanding the difference between Map Apply (@@@) and Map (/@) [duplicate]

Here's a minimal working example of a problem I'm having: ...
205 views

### Delete rows based on specific periods

I have data (.xlsx format): two columns - data in first column imported as DateObject (dates with specific time), data in second column are numbers (113388.28, 865165.98 etc.). I want to delete the ...
116 views

### Catch and Throw command [duplicate]

I am trying to find the time and maximum height of a projectile motion with air friction however Mathematica is "running" for a really long time and not giving an answer. Is there something wrong with ...
91 views

### Simplify large fractions

Hi i'm quite new with Mathematica and i'm experiencing some problems with Simplify and FullSimplify. I'm dealing with a sistem ...
54 views

### How do I simplify an algebraic equation with respect to a specific variable? [closed]

I have the following equation -- which is all in terms of d: ...
83 views

### NDSolve with known tolerance function

I would like to solve the differential equation: y'[x]=F[y[x],x] with y[0.5]=y0 and x ...
314 views

### Palette button with progress bar

Let's say you have a palette with a button that has to do some time-consuming task when clicked: ...
91 views

### ContourPlot color problems

I tried to use contourplot to a 2D fucntion with rescaled color, the code is given below ...
290 views

### Random walk with fixed initial and final coordinates and the length

Looking at the problem of a random walk in 2D or 3D, I would like to generate several trajectories that start all in some starting point, say, (0,0) in 2D and (0,0,0) in 3D and end up all in a ...
63 views

### NSolve taking too long to solve system of polynomial equations

I am trying to solve a system of polynomial equations (10 variables and 10 equations) using NSolve in an attempt to find all solutions. ...
85 views

### How could I add the WorldMap skin to this parametricPlot3d?

How could I stamp the worldmap inthis sphere of variable radius? I´m interested in the meridian of greenwich (longitude=length=0 Degree) is in the position of the longitude=length=0ºDegree of the ...
205 views

### Multidimensional Numeric Integration

I can't manage to calculate numerically the following multidimensional integral: ...
46 views

### Selecting from a list [duplicate]

OK, I know this must be a simple problem, but right now I'm just stuck and need some advice with this :). I have the following list: ...
41 views

### Specific formatting while exporting some data output into a file

I used the following code ...
192 views

### Strange result of an infinite sum

I have the following definition: o[a_] := Sum[ x^(2 k + 1) Product[(2 i + 1)^2 - a^2, {i, 0, k - 1}]/((2 k + 1)!), {k, 0, Infinity}] Now when I evaluate ...
257 views

### NdSolve problem :NDSolve::ndode: Input is not an ordinary differential equation

I am new to Mathematica. I am working on solving the following different equations numerically written in the code as below. Not so sure about the boundary values that depends on R (M(0)=0, n(1)=0) ...
412 views

### How can I draw a square root spiral? [duplicate]

I found this picture on the net. How can I reproduce it in Mathematica?
78 views

### How to reset the “front end” to a 200% default

I wish that when Mathematica is run the "front end" this default to 200%, and perhaps other things where you can not change, as there are directly in the menu. Thank You
438 views

231 views

### Converting between AbsoluteTime and Unix time

By trial and error, I've found that the following gives the current Unix time: AbsoluteTime[] - UPOCH where UPOCH can be defined in any of the following ways: ...
430 views

### Extracting road curves from an image

I have taken several gps readings while driving around town. ...
44 views

### How do I complete this function len for the length of a line segment?

I need to have len[{{x1,y1},{x2,y2}}] is Sqrt[(x2-x1)^2+(y2-y1)^2]. The beginning of the function will be defined as ...
56 views

### return multiple properties of financialdata

Sorry, very silly newbie question.. regarding FinancialData, how to return multiple specified properties. eg. if I want Open & Close properties , or perform an operation such as Open-Close ...
63 views

### Implicit region is not “valid” in ParamatricNDSolveValue function?

I am trying to solve a geometric problem with relation to my Schrodinger equation and its boundaries. Here is my code: ...
18 views

### Collecting and simplifying polynomials [duplicate]

I want simplify some expressions but also using an ordered form for a polynomial. Collect[..., Q, Simplify] should do the job, but sometimes the results does not ...
75 views

### Better control of vertex positions in GraphPlot?

I am trying to graphically visualize a sort of a transformation network. My program generates a list of vertices and edges and I want to turn that into a visually clear graph fulfilling a few ...
257 views

### Solving the symbolic quadratic equation ax2 + bx + c = 0 [closed]

I need to ask Mathematica to solve the symbolic quadratic equation ax2 + bx + c = 0. Does it give you the right answer?
127 views

### Surface Plot 3D of a strongly concave shape

I have a list of {x,y,z} points that all lie on the surface of an object (model output from COMSOL). I would like to generate a graphics object that reproduces the surface. Ideally, I would like ...
193 views

### Is there a bug in MatrixExp in Mathematica v10?

I'm trying to compute MatrixExp[-I t {{0, 1/2, 0, 0, 1/2}, {1/2, 0, 1/2, 0, 0}, {0, 1/2, 0, 1/2, 0}, {0, 0, 1/2, 0, 1/2}, {1/2, 0, 0, 1/2, 0}}] With ver 9 the ...
210 views

### Dynamic arrays and lists with compile (Append, Linked lists etc.)

I have a code that I need to compile. The code contains a loop in which I need to gather data into a list. The question is how to best gather data so that the code works inside Compile. The following ...
47 views

### Having trouble reading this output (pure functions) [duplicate]

I'm after decoupling some odes and trying to solve them using mathematica but my output is in terms of Functions and InverseFuntions and I'm afraid I have no idea how to translate the output into ...
125 views

### How to add a static JPEG into a Manipulate without slowing it down

I´m trying to add an image from a book into a Manipulate but it makes the Manipulate update very, very slowly. So much so that ...
92 views

### Problem with the BarChart3D function

I have a list of values {x,y,z} and I would like to create a 3D bar chart with axis x,y,z . ...