Reading a file incrementally
View only the new entries in a growing log file
Let $f$ be a continuous function on a set $E$.  Is it always true that $f^{-1}(A)$ is always measurable if $A$ is measurable?  I say no.  We know that $\bar{\psi(x)}:=\frac{\phi(x)+x}{2}$ where $\phi$ is the Cantor (or Cantor-Lebesgue) function and $\bar{\psi}:[0,1] \rightarrow [0,1]$.  We know this function maps a measurable subset of $C$ (the Cantor set) into a non-measurable set $W$.  A few observations about $\bar{\psi(x)}$.  It is strictly increasing and continuous, so it has a continuous inverse $\bar{\psi(x)}^{-1}$.  Thus $\bar{\psi(x)}^{-1}(W)=c \subset C$; that is, $\bar{\psi(x)}^{-1}(W)$ is non-measurable, but c is.  Is this correct? Source shell script automatically in terminal How can I automatically source a particular shell script when I open a terminal window by right clicking somewhere and choosing "open in terminal"?  For example, every time I open a terminal I need to run the following command line:  source myscript   How can I make it so that I don't have to type this automatically?  My script is written in tsch:  #!/bin/tcsh setenv DISPLAY 127.0.0.1:10.0 cd /ast/dcm/data   I'm using CentOS 7. Why is it "have someone wrapped around your LITTLE finger"? I just had occasion to write she's got him wrapped around her finger (under complete control).  I'd never really thought about this one before, but my guess would have been the idiom had some connection to wedding rings. On the other hand, intuition (and a Google Books search) tell me that the expression usually involves a little finger - not normally associated with wedding rings.  Does anyone know when/why the idiomatic usage arose? I can't find anything in OED or a cursory search online. How do I change my Minecraft username? Background Video is shown in Rendered mode but not when szene is rendered I run below command on ubuntu 16.4 :  sudo add-apt-repository ppa:noobslab/apps  of below question:    and get below error:  Traceback (most recent call last):   File "/usr/bin/add-apt-repository", line 11, in &lt;module&gt;     from softwareproperties.SoftwareProperties import SoftwareProperties, shortcut_handler   File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 27, in &lt;module&gt;     import apt_pkg ModuleNotFoundError: No module named 'apt_pkg' Error in sys.excepthook: Traceback (most recent call last):   File "/usr/lib/python3/dist-packages/apport_python_hook.py", line 63, in apport_excepthook     from apport.fileutils import likely_packaged, get_recent_crashes   File "/usr/lib/python3/dist-packages/apport/__init__.py", line 5, in &lt;module&gt;     from apport.report import Report   File "/usr/lib/python3/dist-packages/apport/report.py", line 30, in &lt;module&gt;     import apport.fileutils   File "/usr/lib/python3/dist-packages/apport/fileutils.py", line 23, in &lt;module&gt;     from apport.packaging_impl import impl as packaging   File "/usr/lib/python3/dist-packages/apport/packaging_impl.py", line 23, in &lt;module&gt;     import apt   File "/usr/lib/python3/dist-packages/apt/__init__.py", line 23, in &lt;module&gt;     import apt_pkg ModuleNotFoundError: No module named 'apt_pkg'  Original exception was: Traceback (most recent call last):   File "/usr/bin/add-apt-repository", line 11, in &lt;module&gt;     from softwareproperties.SoftwareProperties import SoftwareProperties, shortcut_handler   File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 27, in &lt;module&gt;     import apt_pkg ModuleNotFoundError: No module named 'apt_pkg'   Thanks for help Unable to see anything after importing .obj file I try to import .obj files from this project:  - the files contain Polygon Mesh Data.  When I import the obj file into blender, the outliner shows a new mesh added, but nothing is visible in the 3D viewport:      Any help will be appreciated. Encode URL in JavaScript? How do you safely encode a URL using JavaScript such that it can be put into a GET string?  var myUrl = "http://example.com/index.html?param=1&amp;anotherParam=2"; var myOtherUrl = "http://example.com/index.html?url=" + myUrl;   I assume that you need to encode the myUrl variable on that second line? prove $\frac {ab}{a+b} \geq \sum ^n_{i=1} \frac{a_ib_i}{a_i+b_i}$ "thanks for flagging" popup gets messed up when the comment is automatically deleted For some comments, the comment is automatically deleted when you raise a flag. This includes certain keywords and short +1 comments. But when you raise that flag with the new comment flag interface, the "thanks for flagging" shows up in the top right when the comment is deleted:      As opposed to what happens when you raise a flag on a comment that doesn't auto-delete: How to NOT show keyboard layout chooser popup when changing language in GNOME 3 Since I installed 17.10, when switching language with the assigned keyboard shortcut I get this switcher "window" that obstructs me from typing for a couple of seconds. And yes, a couple of seconds is a huge amount of time when switching languages a lot.      This happens both in X11 and Wayland but doesn't happen (the obstructive window will not appear) when I switch language by clicking on the lang indicator on top bar. Is there any way to tell this window "please go away"? How can I make a time delay in Python? How do I unit test code that includes a callout? Nielsen & Chuang Exercise 2.2 - “Matrix representations: example” Program counter goes to the end of code and 8051 Restarts I have an 8051 MCU which I use keil to program it with C. My problem is that the micro-controller restarts at the end of some functions while they should return.  Using a debugger I tried to check it line by line. And I figured out the the MCU is not restated right after the end of the function. The PC(progam counter) goes to somewhere else (sometime somewhere that there is not any code to execute) and then it increases one by one until the end of code. It is very strange for me because I write my code in C and never seen the type of error previously.    I think this problem might be related to the compiler settings and thus I post the settings here:   Assembler settings: XR GEN DB EP NOMOD51  Compiler settings:  DB OE BR LARGE OPTIMIZE(11, SIZE) DEFINE(SILABS_PLATFORM_WMB912) DEFINE(SILABS_WMCU_SI106x)  Linker settings: CODE REMOVEUNUSED CLASSES(BIT(0x20.0-0x2F.7), DATA(D:0-D:0x7F), IDATA(I:0-I:0xFF), XDATA(X:0-X:0xFFF), CODE(C:0-C:0xFBFF), CONST(C:0-C:0xFBFF))  I tried both large and small settings but the problem remains. Kindly help me if you know the reason. My problem is simple. I think that the strange deformations on the top are there because there are so many vertices in one face. How do I fix this while maintaining nice topology?  Although I triangulated the top polygon, the problem still persists. Why is this limit $\lim_{n \to \infty}(1 + \frac{1}{n})^n$ equal to $e$? I dont get it, if I look at $$\lim \limits_{n \to \infty}\left(1 + \frac{1}{n}\right)^n = e$$    It seems like it should be $1$ because $1 \over n$ is almost zero and $1^\infty$ is still $1$ How to get current CPU and RAM usage in Python? What's your preferred way of getting current system status (current CPU, RAM, free disk space, etc.) in Python? Bonus points for *nix and Windows platforms.  There seems to be a few possible ways of extracting that from my search:   Using a library such as  (that currently seems not actively developed and not supported on multiple platform) or something like  (again no activity since 2007 it seems and no support for Windows). Using platform specific code such as using a os.popen("ps") or similar for the *nix systems and MEMORYSTATUS in ctypes.windll.kernel32 (see ) for the Windows platform. One could put a Python class together with all those code snippets.   It's not that those methods are bad but is there already a well-supported, multi-platform way of doing the same thing? Migrated question's answers can be upvoted twice by the same user are more efficient than ordinary upright bicycles, and  are even more efficient. Then why do we see them so rarely on the road? Is it because they are expensive, or are there some non-financial, significant disadvantages?