i need to validate differents input value lengths.   Inputs value can have a max length of 6 / 15 / 25 characters. Now i was asking to my self if it's a good practice use only one dynamic regex to validate differents max lengths, instead of copy paste the same regex.   During my research i found that i've to use the the const regex = new RegExp()  the problem is that i tried     const lengthValidation = () =&gt; {   const maxLength = 4;   const inputValue = 'ciao';   const regex = new RegExp(`/^.{6,${maxLength}}$/`);   const isValid = regex.test(inputValue);   return console.log('regexTest', isValid); };  lengthValidation();     but it's invalid.   where is my mistake ?
I would like to create a String.replaceAll() method in JavaScript and I'm thinking that using a regex would be most terse way to do it.  However, I can't figure out how to pass a variable in to a regex.  I can do this already which will replace all the instances of "B" with "A".  "ABABAB".replace(/B/g, "A");   But I want to do something like this:  String.prototype.replaceAll = function(replaceThis, withThis) {     this.replace(/replaceThis/g, withThis); };   But obviously this will only replace the text "replaceThis"...so how do I pass this variable in to my regex string?
How do I figure out the right size font / text for a given read distance? Let $A$ be the set of all functions $f:\mathbb{R}\to\mathbb{R}$ that satisfy the following two properties. Let $A$ be the set of all functions $f:\mathbb{R}\to\mathbb{R}$ that satisfy the following two properties:  (1) $f$ has derivative of all orders, and  (2) for all $x,y \in \mathbb{R}$, $f(x+y)-f(y-x)=2xf'(y)$.  Which of the following sentences is true?  (a) Any $f\in A$ is a polynomial of degree less than or equal to 1  (b) Any $f \in A$ is a polynomial of degree less than or equal to 2  (c) $\exists f \in A$ which is not polynomial  (d) $\exists f \in A$ which is a polynomial of degree 4  It is a problem from TIFR GS-2018. I have found polynomials upto degree 2 hold this properties but have to exclude the possibility of (c) and (d). I also found out if $f'(x)$ has at most one real root and clearly graph of $f$ is symetric about that root. How can I proceed further? How can I remove a key from a Python dictionary? Running own executable on Android shell I need a specific command line tool and I have made a C program in my Linux shell. I have compiled the program with an ARM cross-compiler. I have then moved the program into the Android file system and tried to run it.  The output is permission denied.  What do I have to do, in order to run my own compiled programs in Android file system? I am unable to find the link for downloading Ubuntu 16.04 onto my   desktop/laptop. I am able to see the link only for 18.04, but I need 16.04. Minecraft Forge 1.7.10 will not start My minecraft will not start on only that version, I have a Windows 7 computer with Java 8u20 installed, because the latest java 7 update will not work at all(plus imma dev for other stuff).   [22:26:39] [main/INFO] [LaunchWrapper]: Loading tweak class name   cpw.mods.fml.common.launcher.FMLTweaker  [22:26:39] [main/INFO] [LaunchWrapper]: Using primary tweak class name   cpw.mods.fml.common.launcher.FMLTweaker  [22:26:39] [main/INFO] [LaunchWrapper]: Calling tweak class   cpw.mods.fml.common.launcher.FMLTweaker  [22:26:40] [main/INFO] [FML]: Forge Mod Loader version 7.10.25.1208 for Minecraft   1.7.10 loading  [22:26:40] [main/INFO] [FML]: Java is Java HotSpot(TM) 64-Bit Server VM, version   1.8.0_20, running on Windows 7:amd64:6.1, installed at C:\Program   Files\Java\jre1.8.0_20  [22:26:40] [main/INFO] [LaunchWrapper]: Loading tweak class name   cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker  [22:26:40] [main/INFO] [LaunchWrapper]: Loading tweak class name   cpw.mods.fml.common.launcher.FMLDeobfTweaker  [22:26:40] [main/INFO] [LaunchWrapper]: Calling tweak class   cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker  [22:26:40] [main/ERROR] [LaunchWrapper]: Unable to launch  java.util.ConcurrentModificationException     at java.util.ArrayList$Itr.checkForComodification(Unknown Source) ~[?:1.8.0_20]     at java.util.ArrayList$Itr.remove(Unknown Source) ~[?:1.8.0_20]     at net.minecraft.launchwrapper.Launch.launch(Launch.java:117) [launchwrapper-  1.9.jar:?]     at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.9.jar:?]  Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and   will likely be removed in a future release Why does dpkg give me this parsing error? freezing header in a table in html Does magic missile hit silent image's illusory creature? Is there anything like “cubic formula”? When app is moved to SD card, where is the app data stored on SD card? Remove "Show Desktop" button next to the clock in Windows 7 How does passive perception work Total noob question, but the passive perception is confusing. I don't understand how to calculate it or use it, and I need help. iPad 1 update from 5.1.1 to 7.1 How can I update iPad 1 from iOS 5.1.1 to iOS 7.1?  I tried checking for updates but I get a message "your software is up to date". I am new to working with IDS' such as Suricata/Snort. I am currently trying to using Suricata to log DNS requests and responses to malicious domains on my network. On my DNS server I made it so that any request to say, bad.com, would resolve to 127.0.0.1, thus not allowing anybody on my network to access that site.   I have set up Suricata to log all DNS requests, but how do I filter that down and narrow it and tell it to only log requests to 127.0.0.1 and let everything else go unlogged?   I tried to create a rule:  alert dns any any -&gt; 127.0.0.1 any (msg: "BLACKLISTED WEBSITE"; flow:to_client; content:"rrname";sid:2240001;rev:1;)   But that did not work.   What do I need to do to only log DNS requests to certain IPs? I cannot find any information in the documentation or anywhere else on the internet.   Thanks. why do academics write peer reviews? Proving an inequality by induction, how to figure out intermediate inductive steps? I'm working on proving the following statement using induction:  $$ \sum_{r=1}^n \frac{1}{r^2} \le \frac{2n}{n+1} $$  Fair enough. I'll start with the basis step:  Basis Step: (n=1) $$ \sum_{r=1}^n \frac{1}{r^2} \le \frac{2n}{n+1} $$ $$ \frac{1}{1^2} \le \frac{2}{1+1} $$ $$ 1 \le 1  \checkmark  $$  Inductive Step: $$ \sum_{r=1}^{n+1} \frac{1}{r^2} \le \frac{2(n+1)}{(n+1)+1} $$ $$ \sum_{r=1}^{n+1} \frac{1}{r^2} \le \frac{2(n+1)}{n+2} $$  My goal is to prove $\forall_{n\ge1} s(n) \implies s(n+1) $ or that this inequality holds true for all $n\ge1$.  I'm not quite sure to go from here on the inductive step. I understand that I need to basically work some clever substitution and manipulation into the problem to end up with: $$ \sum_{r=1}^{n+1} \frac{1}{r^2} \le \frac{2n}{n+1} $$  However, I'm not quite sure what needs to done to obtain this after attempting a few times. Helllo!  For a project that I am doing, I need to render the my model to a sprite sheet. This is all fine, except that the model has a cloak, which uses a cloth animation. I need to smoothly transition from the end of the cloth simulation to the start, so it doesn't just jerk back, but I can't find any way of doing this.  Thanks in advance. Category of Grp is not a subcategory of Set Why isn't the gamma function defined so that $\Gamma(n) = n! $?