I'm currently working on converting  voice recording module to accept power from a 9V power supply. I have successfully soldered the battery connections so the chip can be powered from two wires. When I connect the two wires directly to a 3.3~ishV power supply unit, the chip performs record and playback flawlessly. But when I attempt to wire it to a voltage divider, to wire down the voltage from 9v to the operating 3.3~ishV, the voltage going to the chip only appears to get around 2V (as opposed to the 3.45 that I would suspect). I tried increasing the input voltage from 9V to 12V and the chip still wants to hold at 2V.  Any ideas as to why this is happening? I suspect it has something to do with current, but I left my smarty pants at home today.
When would you use a voltage regulator vs a resistor voltage divider?  Are there any uses for which a resistor divider is particularly bad?
Why can't this be done with Master Theorem Apparently recurrences like this cannot be solved with the Master Theorem:  $T(n) = 2T\left(\frac{n}{2}\right) + \frac{n}{\log(n)}$  Because $n^{\log_b(a)} = n^1$ is not a polynomial multiple of $f(n) = \frac{n}{\log(n)}$ since $\frac{n}{\frac{n}{\log(n)}} = \log(n)$, which is less than $n^\epsilon$ for any positive $\epsilon$.  But when is this really even an issue?   For example why wouldn't the time complexity be $n \log n$ using case 2 of the Master Theorem? Unrolling the recursion:  $$T(n) = n\sum_{k=1}^{\log_2(n)} \frac{1}{\log_2(2^k)}$$  $$T(n) = n\sum_{k=1}^{\log_2(n)} \frac{1}{k}$$  Doesn't this suggest $\Theta(n \log n)$ even though it supposedly cannot be done with Master Theorem? Ubuntu 20.04 on DualBoot fail 90% of tries - Initramfs unpacking failed: Decoding failed I just installed Ubuntun 20.04 on a Dell Latitude 7400 on DualBoot. I had to remove the RST as mentioned on this post :  It works but now I need to test 5 or more times to boot. After the grub screen, most of the time i have a black screen. Sometimes I have this error : Initramfs unpacking failed: Decoding failed And then it starts.  here is a file called initramfs.conf cat /etc/initramfs-tools/initramfs.conf MODULES=most  BUSYBOX=auto  COMPCACHE_SIZE=&quot;&quot;  COMPRESS=lz4   DEVICE=  NFSROOT=auto RUNSIZE=10% Does a Grapple or Shove count as an attack for the Mobile feat? The  feat enables you to not get opportunity attacks from creatures you try to attack.  Does it still apply if the attack you made was a Grapple or Shove ? In preparation for the eventual deployment of full HTTPS support on Stack Exchange, and also to make the currently available "alpha" HTTPS support more usable, all links from Stack Exchange sites to other Stack Exchange sites should be .  Currently, at least the following places still feature links with explicit http: protocol prefixes:   the page footer, the "Hot Network Questions" and "Community Bulletin" modules in the sidebar,  (the site switcher menu is OK, though),   and, of course,   lots and lots of user-supplied links in post and comment content.   I've posted this feature request with the intent to provide a single central place for tracking these issues, rather than having them scattered across multiple meta threads.  If you find more places on SE where protocol-relative links should be used, please report them below.  I fully expect this request, in its full sense, to be treated as  for the time being; however, these issues do need to be fixed at some point before our HTTPS support is ready for "prime time".  Ps. Yes, the next release of  (v1.10) is going to include a general client-side fix for most of these issues.  In the mean time, the  plugin effectively provides the same functionality, and much more besides. ++ is dangerous for C programmers Why are all snaps being mounted and listed as block devices or partitions for Ubuntu 18.04? How to import footage in the VSE for optimal playback and organization? How to import footage in VSE for optimal playback and organization, using proxies and workarounds? I have keypair (u,r), and two pieces of data, X and Y.  I reveal X publicly but keep Y secret. Y has high entropy.  I then concatenate X and Y, into Z.  I encrypt Z, into "encrypt(Z,u) = Q". r is needed to decrypt Q back into Z.  Later, (when it doesn't matter), r will be revealed and everyone will decrypt Q into Z. At that point, everyone will know that, all along, Q "contained" X. Can I prove that Q contains X before r is revealed (including interactive zero-knowledge proofs)? Evaluate: $\lim_{n\to\infty}\left({2\sqrt n}-\sum_{k=1}^n\frac1{\sqrt k}\right)$ Or, an introductory guide to robust filename handling and other string passing in shell scripts.  I wrote a shell script which works well most of the time. But it chokes on some inputs (e.g. on some file names).  I encountered a problem such as the following:   I have a file name containing a space hello world, and it was treated as two separate files hello and world. I have an input line with two consecutive spaces and they shrank to one in the input. Leading and trailing whitespace disappears from input lines. Sometimes, when the input contains one of the characters \[*?, they are replaced by some text which is is actually the name of files. There is an apostrophe ' (or a double quote ") in the input and things got weird after that point. There is a backslash in the input (or: I am using Cygwin and some of my file names have Windows-style \ separators).   What is going on and how do I fix it? How do the Goodman-Kruskal gamma and the Kendall tau or Spearman rho correlations compare? In my work, we are comparing predicted rankings versus true rankings for some sets of data. Up until recently, we've been using Kendall-Tau alone. A group working on a similar project suggested we try to use the  instead, and that they preferred it. I was wondering what the differences between the different rank correlation algorithms were.  The best I've found was , which claims Spearman is used in place of usual linear correlations, and that Kendall-Tau is less direct and more closely resembles Goodman-Kruskal Gamma. The data I'm working with doesn't seem to have any obvious linear correlations, and the data is heavily skewed and non-normal.  Also, Spearman generally reports higher correlation than Kendall-Tau for our data, and I was wondering what that says about the data specifically. I'm not a statistician, so some of the papers I'm reading on these things just seem like jargon to me, sorry. For valuation rings I know examples which are Noetherian.      I know there are good standard non Noetherian Valuation Rings. Can anybody please give some examples of rings of this kind?    I am very eager to know. Thanks. Should you set all the objects to null (Nothing in VB.NET) once you have finished with them?   I understand that in .NET it is essential to dispose of any instances of objects that implement the IDisposable interface to release some resources although the object can still be something after it is disposed (hence the isDisposed property in forms), so I assume it can still reside in memory or at least in part?  I also know that when an object goes out of scope it is then marked for collection ready for the next pass of the garbage collector (although this may take time).  So with this in mind will setting it to null speed up the system releasing the memory as it does not have to work out that it is no longer in scope and are they any bad side effects?  MSDN articles never do this in examples and currently I do this as I cannot  see the harm. However I have come across a mixture of opinions so any comments are useful. Group presentation for discrete Heisenberg group Where are the default settings saved for the Command prompt defaults? Is there a simple way to add exFAT support? When I insert a USB stick or camera flash card I get the following error:  unknown filesystem type 'exfat'   Is there a simple way to add exFAT support to Ubuntu without kernel patching? How to setup Java-Home and Path in Ubuntu 12.04 Find the infinite sum of the series $\sum_{n=1}^\infty \frac{1}{n^2 +1}$ This is a homework question whereby I am supposed to evaluate:  $$\sum_{n=1}^\infty \frac{1}{n^2 +1}$$  Wolfram Alpha outputs the answer as   $$\frac{1}{2}(\pi \coth(\pi) - 1)$$  But I have no idea how to get there. Tried partial fractions (by splitting into imaginary components), tried comparing with the Basel problem (turns out there's little similarities), nothing worked. Determining size of grid cells created by vector grid tool of QGIS? I am working with QGIS 1.8.0 and Im making a vector grid on a map. Does someone know how big are the squares if the grid settings look like in the picture? How does the Girl-Genius web-comic relate to the Agatha H. books? After spending some time reading  I was convinced to buy the book.  I've ordered what I think is the  in my local bookstore (yay local) and it seems to relate to the first one or two years of of web content, but I can't be sure.  My question is: "how does the book series line up with the Web comic?"  Does it contain specific episodes/adventures, relate to strips from a specific time-span or is it simply an assortment of episodes?  UPDATE: They are amazing.  It is interplanetary war in the introduction!!!!  Yes!