# All Questions

38 views

### Reducing quantile & color map queries for use with Associations

This set of queries perform basic maps to quantile and then color-map. There's got to be a more compact solution. What are some approaches to reduction? Numeric: ...
93 views

What I did: ...
120 views

### Appending elements to a list in parallel table

Is there any way to store values in a list that is being computed in parallel? For example, if ParallelTable is computing some ...
213 views

### How to imitate list comprehensions for constant arrays?

In Python, ['a'] * 10 generates ['a', 'a', 'a', 'a', 'a', 'a', 'a', 'a', 'a', 'a'] and ...
78 views

### Why does this Graphics3D example change lighting on reorient?

What I do: Graphics3D[{Sphere[]},Lighting -> "Neutral"] What I get: but when I reorient: What I want: a stable result! PS The Platform is Wolfram ...
37 views

### If a given # is 70% of X. How do you determine what X is? [on hold]

given I have the number 50,000 which is 70% of X. How do I calculate what X is without guessing. Thanks
164 views

### Inefficient NIntegrate and Which

In version 10 a simple numerical integraton of piecewise function is highly inefficient: ...
216 views

### Problems finding intersection points between line and generic function

I'm trying to find Intersection points between a line, which is given by 2 points, and a generic function (I want it to be able to handle polynomial functions, circles/ovals, lines and all ...
34 views

### How to change number form of Plot Legend in ListContourPlot? [on hold]

I am creating a ListContourPlot from some very large values. I would like these numbers to be written out in scientific notation (8x10^8, etc.) I've tried the following code: ...
50 views

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87 views

### How to write a loop

I try to create a table which will describe traffic paths at a crossroads. Instead of using copy-paste repeatedly, I would like to write a loop. For example: ...
47 views

### How to produce timely spoken text?

On my system (Mac OSX 10.10.4) the following code produces only the first utterance. The second one is produce when the user interacts in some way with the front end (mouseover, mouseclick). How can I ...
176 views

### Systemic bugs in GraphPlot and related functions such as TreePlot and TreeForm

Bug introduced in 7.0.1 or earlier and persisting through 10.2.0 I believe I have come across a rather curious bug in TreeForm: ...
8 views

### Don't understand about how to solve the first equation with Gauss Elimination [migrated]

Please take a look at the picture. My quesion is: How to solve the first equation with Gauss Elimination that is displayed in the picture. I don't understand HOW.
44 views

### Inputting values into the variables without having to input the matrix all over again

I'm practicing using LU decomposition on Mathematica. I am able to find the L & U matrices, specifically the variables. However, i find it tedious having to input the newly found values and form ...
267 views

### Implementing Picard's Iteration for solving ODEs

Picard's Iteration is a way of solving the IVP $$y'(x)=f(x,y(x)), \quad y(x_0)=y_0$$ It consists of defining the following sequence of functions recursively: y_0(x):=y_0 \\ ...
121 views

### Equation involving hypergeometric functions

I want to solve this equation but nor NSolve nor Solve are able to do this. ...
240 views

What I did: ...
36 views

### Override a PlotTheme element at the Options level?

Plot properties defined in a Theme override (supersede) properties defined on Options. This can be undesirable in a case such as: ...
4 views

### How to solve a equation task [migrated]

I have found a equation task that is: y=0,5x+2,5 y=3x-1 The answer and its process is: ...
40 views

### How to segment letters and text blobs?

This new article from Google research describes how their Translate app preprocesses an image on a phone before applying convnets: It needs to weed out background objects like trees or cars, and ...
76 views

### How to make a Nebulabrot?

A Nebulabrot is a generalization of the Buddhabrot, a fractal rendering technique related to the Mandelbrot set that sort of looks like a meditating buddha. The Buddhabrot rendering technique was ...
262 views

### What Method options does FindInstance accept?

While answering Trouble getting FindInstance to return multiple results for certain constraints it became clear that for this problem FindInstance would be better ...
105 views

### How may I avoid ParametricPlot3D clipping? [duplicate]

What I am doing: ParametricPlot3D[{Cos[z/2]^6 * Cos[t],Cos[z/2]^6 * Sin[t], z}, {t,-Pi, Pi},{z,-Pi,Pi}] What I get: What I want: what I get, but without the ...
90 views

What I did: ...
71 views

### Find sub-sets of vanishing additions or subtractions from a list?

Let's say I have a list L containing n numerical numbers. Now I want to find all sub-sets of ...
21 views

### Vector field plot not appearing in VectorPlot3D

I am having trouble in plotting the vector fields - Bfield and Avector - with the VectorPlot3D function. Here is the code used to Compute Bfield and Avector: ...
65 views

### How to disqualify a rule [on hold]

Executing this line Assuming[x < 0, x -> 10] Expected output: False Say x -> 10 is a root of a polynomial ...
196 views

### How to monitor the progress of training a classifier?

I've had p = Predict[x -> y] running for hours and I have now idea if I should kill it or not. I'm looking for some rough bounds for an estimate of how long ...
27 views

I have ...
38 views

### How to define a function deriv[f[x]] such that its output is an unevaluated expression fx=D[f[x],x]?

I want to define a function deriv[f_[x_]] such that when I run deriv[f[x]], the output is an unevaluated expression ...
37 views

### What can I use as an equivalent of python zip in mathematica inside of Sum[]? [on hold]

I want to take two lists of the same length: widths and weights, and sum a function (of 3 variables) over a single index using the elements from both lists that have that index. Then I want to plot ...
1k views

### Insphere for Irregular Tetrahedron

I am looking for existing Mathematica code to compute the unique sphere inscribed inside an irregular tetrahedron. I can write it myself, but I would love to find that someone already performed this ...
35 views

### Error Resulting from Placing a Dynamic Variable inside of Table

I want to create a list of values, True or False, and to update those values with a ...
59 views

### What am I missing in this highly oscillatory integral?

I want to numerically integrate this equation (in python without calling Mathematica): $\int_0^\infty {\rm d}k f(k) J_v(r k) J_n(s k)$ where $f(k)$ is a non-smooth function, $J_v$ are the Bessel ...
49 views

### Count participation of variable list

I have the directed edges of a graph given by a list of variable (vertex) pairs. ...
123 views

What I did: ...
50 views

### Where's the service status page for Programming Cloud?

I've searched wolframcloud.com and found none. It would be good to know, because I am getting a range of apparently random failures from "Tag List ... is Protected" to "possible crash" (!) to "Cloud ...
58 views

92 views

### Iterator variable not blocked in ParametricPlot

Bug introduced in 10.0 and persisting through 10.2 or later It appears that perhaps the iterator variable r is not Block-ed ...
167 views

### Using Simplify on a consistent system returns False

Bug introduced in 8.0 and persisting through 10.2 or later It's late, but am I missing something here? Why should two independent equations, which together are consistent, ...
202 views

### Bug in plotting function using FindMinimum?

Bug introduced in 10.0 and persisting through 10.2 or later While working on an answer to RegionPlot from NDSolve, I came across this strange behavior of ...
106 views

### LogLogPlot plugs in zero

Bug introduced in 10.0 and fixed in 10.0.2 In testing the answers to Plot result of non analytical-integral in V10.0.1, I came across this behavior of ...
31 views

### Tracking features where ImageFeatureTrack finds none?

How is it possible to track common features in the following sequence of images (e.g. holes or corner points along the top margin), ? I have had no luck with ...