I am pretty new to Angular and I am writing a simple if statement to check if my property isn't one 10 things. Is there a Not In or filter from enums or from a list?  public type: string; if(type === '1' || type === '2' || type === '3') || type === '4'){ // do something } else { //do something else }   I am looking for something simple if we can use like  if(type not in (1,2,3))   What is the best way to check the scenario like this against the string?
What is the most concise and efficient way to find out if a JavaScript array contains a value? This is the only way I know to do it: function contains(a, obj) {     for (var i = 0; i &lt; a.length; i++) {         if (a[i] === obj) {             return true;         }     }     return false; }  Is there a better and more concise way to accomplish this?
Is Java's default value for Boolean 'true'? Converting a number with comma as decimal point to float I noticed the other day when serving the public that when asking for something, people were saying "Can I get an xyz, please". The previous time I had such a job it was "Could I have an xyz", or "May I have..." if they were being very polite.  Does anyone know when this trend started and what caused it? What's the use of a decoupling capacitor near a reservoir capacitor? I've seen some circuits where a decoupling capacitor is used as well as a reservoir capacitor, like this (C4 and C5):    I've read about  and for me it looks as if they are meant to remove small fluctuations in the supply voltage. Then I thought - wasn't that the purpose of a  as well? Why wouldn't the reservoir capacitor be able to filter out the small fluctuations, if it is able to filter out the large fluctuations?  So I feel like I have a basic misunderstanding here. What is the purpose of a decoupling capacitor next to a reservoir capacitor, when we assume we place both equally near to the power consuming part? Or is the only advantage of the decoupling capacitor that it is smaller and can therefore be easily placed more near to the power consuming part? I understand that you have to have visas to enter some countries, but I was wondering whether you have to pay for each visa separately or you can get a visa to go everywhere. You see videos and lists on what you should pack to travel the world, but no lists on the documentation needed. What are the integer solutions to $a^{b^2} = b^a$ with $a, b \ge 2$ I saw this in quora.  What are all the integer solutions to $a^{b^2} = b^a$ with $a, b \ge 2$?  Solutions I have found so far:  $a = 2^4 = 16, b = 2, a^{b^2}  = 2^{4\cdot 4} =2^{16}, b^a = 2^{16} $.  $a = 3^3, b = 3, a^{b^2} = 3^{3\cdot 9} =3^{27}, b^a = 3^{3^3} =3^{27} $.  In the general case, $a$ and $b$ have the same set of prime divisors, so let $a =\prod_P p_i^{a_i}$, $b =\prod_P p_i^{b_i} $ with each $a_i \ge 1, b_i \ge 1$.  $b^a =b^{\prod p_i^{a_i}} =(\prod p_j^{b_j})^{\prod p_i^{a_i}} =\prod p_j^{b_j\prod p_i^{a_i}} $  $a^{b^2} =a^{\prod p_i^{2b_i}} =(\prod p_j^{a_j})^{\prod p_i^{2b_i}} =\prod p_j^{a_j\prod p_i^{2b_i}} $  Therefore, for each $p_j$, $b_j\prod p_i^{a_i} =a_j\prod p_i^{2b_i} $.  I haven't gotten any further than this.  I conjecture that there are no other solutions. Stop making iPhone constantly change sound volume on its own? I regularly get interrupted in watching and listening to video by the volume randomly getting lowered without me asking for it. I get a system notification telling me &quot;the volume was lowered&quot;, telling me it's protecting my hearing based on the last 7 days of use. I've never been asked about enabling such a feature. I have already disabled what relevant items I can find under Sound &amp; Haptics, which is given as the source of the notification. It apparently doesn't matter though because it's not being respected. How can I make this stop? iPhone 8, iOS 14.2 How do you empty the buffers and cache on a Linux system? Prior to doing some benchmarking work how would one free up the memory (RAM) that the Linux Kernel is consuming for its buffers and cache?    Note that this is mostly useful for benchmarking. Emptying the buffers and cache reduces performance! If you're here because you thought that freeing buffers and cache was a positive thing, go and read . The short story: free memory is unused memory is wasted memory. Making sense of principal component analysis, eigenvectors & eigenvalues In today's pattern recognition class my professor talked about PCA, eigenvectors and eigenvalues.   I understood the mathematics of it. If I'm asked to find eigenvalues etc. I'll do it correctly like a machine. But I didn't understand it. I didn't get the purpose of it. I didn't get the feel of it.        I strongly believe in the following quote:     You do not really understand something unless you can explain it to your grandmother. -- Albert Einstein   Well, I can't explain these concepts to a layman or grandma.   Why PCA, eigenvectors &amp; eigenvalues? What was the need for these concepts? How would you explain these to a layman? Calling a function from a string in C# How should I phrase a question that must be answered with an ordinal number (e.g., the third prime)? How to convert milliseconds into human readable form? I need to convert an arbitrary amount of milliseconds into Days, Hours, Minutes Second.  For example: 10 Days, 5 hours, 13 minutes, 1 second. bash: start multiple chained commands in background I'm trying to run some commands in paralel, in background, using bash. Here's what I'm trying to do:  forloop {   //this part is actually written in perl   //call command sequence   print `touch .file1.lock; cp bigfile1 /destination; rm .file1.lock;`; }   The part between backticks (``) spawns a new shell and executes the commands in succession. The thing is, control to the original program returns only after the last command has been executed. I would like to execute the whole statement in background (I'm not expecting any output/return values) and I would like the loop to continue running.  The calling program (the one that has the loop) would not end until all the spawned shells finish.  I could use threads in perl to spawn different threads which call different shells, but it seems an overkill...  Can I start a shell, give it a set of commands and tell it to go to the background? If I upload my brain into a computer is it still me? I think the answer is yes but I know a lot of people disagree. So, I would like to ask these people when exactly does it stop being me.  Let's say I want to upload my brain into a computer using the following procedure:  I have each of my neurons replaced by electronic neurons. By electronic neurons I mean chips with the necessary hardware and software to perform the exact same function that the neuron being replaced was performing. This means that given the same inputs that the biological neuron was given it would produce the same outputs. Then I connect that electronic neuron to all the neurons that former biological neuron was connected to.   At the end of this process is it still me? If not when did it stop being me? When one neuron was replaced? When 1,000 were replaced? When 1,000,000 were replaced?  (assuming it is still me)  Then, I divide these electronic neurons into groups and for each group I perform the following:   Write software to simulate the group of electrical neurons in my computer such that given the same inputs that go into the group of electronic neurons in my brain, it will produce the same outputs. Replace each group of neurons with another chip that communicates with my computer. Each of the chips will communicate to the corresponding software module in order to determine how to transform its inputs into the necessary outputs. Connect all of the inputs and outputs of the group of electronic neurons to that new chip.   At the end of this process is it still me? If not when did it stop being me? When one group was replaced? When 1,000 were replaced? When 1,000,000 were replaced?  (assuming it is still me) Now, what I have is a bunch of these new chips in my head, connected to each other and for each of these chips I have a small neural network software module in my computer. So, now for each pair of chip/software module I do this:   Transfer all connections going into and out of the chip into the computer version (i.e. connect the software module to the other software modules that represent the other chips that this chip is connected to) Disconnect the chip from the other chips and remove it   At the end of this process is it still me? If not when did it stop being me? When one of the new chips was replaced? When 1,000 were replaced? When 1,000,000 were replaced?  If it is still me then I have successfully moved my brain into a computer without ceasing being myself.  So, again the question is if at the end it is not me anymore when exactly does it stop being me and why does it stop being me?  EDIT: This question assumes that our universe and everything in it (including ourselves) follows the (testable) laws of physics. As it stands it also assumes that neuroscience is mostly right, although the question could also be considered without that requirement if instead of neural simulations we were to implement physics simulation of the brain. Of course this is a lot less practical. However, if your view is that our minds have a supernatural component then the question does not make any sense.  It was also pointed out that this is related to the Ship of Theseus, i.e. is something still the same if all its parts have been changed. With regards to that I think it is useful to consider that most of the cells in our body (not including brain cells) are regularly replaced anyway and some people even get entire organs replaced. Yet, we don't say that they stopped being themselves. Note, however, that if you are assuming a supernatural component of the mind that this explanation is not really adequate or relevant. Can a familiar attune and wear or use a magic item? Is it possible for a familiar to attune to and then wear or wield a magic item? Is there a way to find self-answers with the advanced search? Preferably, not using the  and including results of all time and not just the recent ones with the new share your knowledge, Q&amp;A-style I've got a Windows 10 Computer (home edition), which has 4GB of Ram and an i5 processor. I need to run an old 32 bit accounting programme. The vendor said it won't release a 64 bit version (although a 64bit version exists, it's missing key features from the older version).  The programme installs fine, but when I click on the programme icon, it says the programme won't work on a 64 bit system.   What options do I have?    I've done a fair bit of research, but it seems to run up dead ends.   1) WoW64     Apparently, this is supposed to let you run 32 bits on 64 bit Windows. However, I am not sure how to install it. I think it's for web servers only. However,  says it can work on Windows 7, but doesn't explain how to set it up (or if it will work on Windows 10).  2) XP mode     A 32bit Windows XP emulator. However, it seems to be for Windows 7 only. Also according to this , you need Windows Professional.   3) Virtual Box Machine    Let's you emulate Windows. Seems overkill for my purposes. Plus I would need to buy a 32 bit Windows license. I think it would run slowly with 4GB of Ram.  4) Partition drive into 32bit and 64 bit versions Apparently, you can use the free tool  to split the drive into two and then install separate 32bit and 64 bit versions.   Again, seems overkill and it looks like I would need buy a 32 bit Windows 10 license.   Are these my only options?     Images  Installation    First run (From the error message I guess it's a 16-bit program)   Clicking on programme For some tests in R, there is a lower limit on the  calculations of $2.22 \cdot 10^{-16}$. I'm not sure why it's this number, if there is a good reason for it or if it's just arbitrary. A lot of other stats packages just go to 0.0001, so this is a much higher level of precision. But I haven't seen too many papers reporting $p &lt; 2.22\cdot 10^{-16}$ or $p = 2.22\cdot 10^{-16}$.   Is it a common/best practice to report this computed value or is it more typical to report something else (like p &lt; 0.000000000000001)? In educational material for the Russian language and linguistic literature the need to put accents on Cyrillic vowels often arises. However when I tried to do this with luaLaTeX the accents where misplaced.  \documentclass[11pt]{article} \usepackage[utf8]{inputenc} \usepackage{fontspec} \setmainfont{Linux Libertine:style=Regular} \begin{document}  Е́сли вы изу́чите  \'{Е}сли вы из\'{у}чите  \'{E}сли вы из\'{y}чите % Here "E" and "y" are Latin glyphs, but this workaround does not                         % work with all Cyrillic letters e.g. Я, Ю \end{document}     The last line would looks nice, but unfortunately these are Latin glyphs.  Is this a problem with the font used (Linux Libertine) or with LaTeX? Changing parameter values according to other parameter choice in Processing script using QGIS 3? I couldn't find anything about this problem.  Suppose to have the first parameters in a Processing script defined as an Enum:     self.addParameter(         QgsProcessingParameterEnum(             self.CHOICE,             self.tr('Choose the parameter'),             ['param1', 'param2']         ) )   While the second one as a number:  self.addParameter(     QgsProcessingParameterNumber(         name=self.VALUE,         description=self.tr('My value'),         type=QgsProcessingParameterNumber.Double,         defaultValue=40,         optional=False,         minValue=0,         maxValue=100     ) )   Is it possible to change the minValue, maxValue, description, ecc.. of the second parameter depending on the first or second choice of the first parameter already in the GUI?  e.g. if the user choose param1 then the second parameter should become:  self.addParameter(     QgsProcessingParameterNumber(         name=self.VALUE,         description=self.tr('My value'),         type=QgsProcessingParameterNumber.Double,         defaultValue=40,         optional=False,         minValue=0,         maxValue=100     ) )   while if he choose param2 it should became:  self.addParameter(     QgsProcessingParameterNumber(         name=self.VALUE,         description=self.tr('My AWESOME value'),         type=QgsProcessingParameterNumber.Double,         defaultValue=0,         optional=False,         minValue=50,         maxValue=500     ) )