# Questions tagged [extract]

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### Extracting solutions from SDE

I have an SDE system which I solve using ...
44 views

### How to extract the last output from the Maximize

Pitty on me! Still a beginner. After using Mathematica for 8 years and spending an hour on google, I remained unsuccessful to find an answer of: How to extract the last element of the output of ...
36 views

### How to specify an element of a list when using RecurrenceTable

My problem is that I'm trying to get a list of refraction angles in a multilayer structure (for the sake of this example - with two types of refraction indices and eleven layers of them). The code is ...
33 views

### Getting 1st element of a nested list, based on criteria for 2nd element [closed]

I have a list such as {{abc,1},{def,2},{ghi,1},{jkl,3}}. I would like to extract elements that have 1 as the second element (ignoring those that have 2 or 3 as their second element). In the case ...
35 views

### Interactively extracting arbitrary portion of elements from a 2D list

I have a 2D list which can be plotted as follows: Image 1 Based on the plotted image, I would like to select some of the shapes on the image and extract the data for further analysis, for example, ...
92 views

### Take $n^\text{th}$ sub-list with equal distances

I have been looking at Span, Take, etc. functions but I couldn't figure out how can I extract elements likes this ...
35 views

### Factorization of multivariable polynomial

I have a polynomials of multivariable for instance: $P=yx+2^4xy+3+5^2xz+3^4zx$ Now I would like to do the following: extract those temrs that only has $z$ . extract terms that only has $y$ express ...
126 views

### How to extract the argument from an in-built function

I would like to extract the argument from : DiracDelta[-10 + x + ξ]
70 views

### Extracting info from Entities

I am trying to look up data of entities, but I imagine I'm not doing it right, or have misunderstood the structure. Here, I try the extract the values of the new SI defining constants, which are ...
155 views

### How to extract a line from a ContourPlot with a condition

I made a ContourPlot of a fuction at the points where its value is zero. So my command is written as follows: ...
79 views

### Extracting values from a list

Consider these lists : ...
123 views

### Extract names from a document [closed]

If I have a document, any document, it can be a book, an article, etc, how could I extract people's names from there? For example, if the input is an article, the output of the function would be the ...
26 views

### Extract and name PNG's from loops [duplicate]

I want to extract PNG files and name them depending on the dummy variable of a loop. For example, starting from ...
57 views

### Extract points from given Line[]

As the title says, I have a Line object like this: Line[{{1,2,3},{4,5,6},...,{7,8,9}}] and want to extract certain points. I ...
92 views

### Extracting a product of factors from an expression in unevaluated form

Suppose I have an expression like so: $\qquad {\rm expr}=2\,i\,{\rm Gamma}(4)\,\pi\, 9.93 f(x)\,g(y) \frac{h(x, 4y)^3}{11 q}$ What is best (most succinct) way to extract out only the product of ...
I have equation: $a+bx+cx^2+dx^3= \dfrac{1}{f+gx+hx^2+ix^3} \dfrac{\partial}{\partial r}(ax+bx^2+cx^3+dx^4) +\dfrac{1}{(f+gx+hx^2+ix^3)^2} \dfrac{\partial^2}{\partial r^2}(ax^2+bx^3+cx^4+dx^5)$ ...
Assume I have a $m\times n$ matrix and I would like to extract four neighbors of randomly selected entry of a matrix. I have handled if location is not on the boundary. Any suggestion how to handle it ...