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## What is the most basic “depth” of any “container file”?

I use the term “container file” to describe any file which practically contains one file or two or more files. Some examples would be a tar archive or a directory. Let’s say I open a tar archive with some archiving GUI software or let’s say I open a directory with some GUI OS file browser […]

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## Is there a standard name for a piecewise log-log curve?

If we have a set of points on the 2D plane $(x_i, y_i)$, $i = 1, 2, \dotsc, n$ (with unique and ordered x-coordinates $x_1 < x_2 < \dotsc < x_n$) and connected them by lines we form a function $y = f(x)$ which we usually call a `piecewise linear’ function. The function $f$ is, […]

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## How to limit access to JMX?

We’re running a large vendor-provided distributed application, and have recently discovered, many of their processes talk JMX on random ports. The JMX-access is completely unprotected, indeed, I was able to connect using jconsole running on my desktop and was able to change logging-levels and create VM-dumps. Data-theft is (probably!) not possible, but denial of service […]

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## Showing that a second degree polynomial is equal to the second order Taylor polynomial of a function

Let $f : \mathbb R^2 → \mathbb R$ be a function. Assume that the partial derivatives of f of order less or equal to two at $(0,0)$ exist. Let $g$ be second degree polynomial such that its first order derivatives (as well as its second order derivatives) are equal to the first order derivatives (and […]

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## How to limit access to JMX?

We’re running a large vendor-provided distributed application, and have recently discovered, many of their processes talk JMX on random ports. The JMX-access is completely unprotected, indeed, I was able to connect using jconsole running on my desktop and was able to change logging-levels and create VM-dumps. Data-theft is (probably!) not possible, but denial of service […]

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## what is the meaning of “had they used their gift”? does it conditional?does “as D.D. Home used his” means that he should followed the advise?

what is the meaning of “had they used their gift”? does it conditional? does “as D.D. Home used his” means that he should followed the advise of the author? To realize their position one has to remember that they were little more than children, poorly educated, and quite ignorant of the philosophy of the subject. […]

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## what is the type of a here

I found this code Lemma foldlP T S f (s : seq T) x0 (I : nat -> S -> Prop) : I 0%N x0 -> (forall i x a, (i < size s)%N -> I i x -> I i.+1 (f x (nth a s i))) -> I (size s) (foldl f x0 s). […]

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## what is the meaning of “in the affections of” in this context?

what is the meaning of “in the affections of” in this context? This strange, eccentric, and formidable man had his proper environment in the 17th century, when his prototypes were holding moorland meetings in Gallo way and avoiding, or possibly even attacking with the arms of the flesh, the dragoons of Claverhouse. But, live when […]

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## Every co-Cauchy Sequence with a Positive Cauchy Sequence is Positive

Indeed, this question arises when one wants to prove the well-definedness of an order while constructing $\mathbb{R}$ from equivalence classes of Cauchy sequences in $\mathbb{Q}$. Definition 1. A Cauchy sequence $a:\mathbb{N}\to\mathbb{Q}$ is positive if and only if it does not converge to $0$ and has a positive tail. More precisly, \$\exists \epsilon\in\mathbb{Q}^+,\,\,\forall N\in\mathbb{N},\,\,\exists n\ge N\land […]

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## Multiple commands and subshell execution after pipeline

Ok, I know that in Bash (by default, without ‘lastpipe’ bash option enabled) every variable assigned after a pipeline is, indeed, executed in a subshell and the variable itself dies after subshell execution. It does not remain available to the parent process. But doing some tests, I came up with this behavior: A) Second command […]