database table is not creating
When does SQLiteOpenHelper onCreate() / onUpgrade() run?
Is it a bad practice to catch Throwable? Ohmic Heating in Wires please could someone tell me why Ohmic losses are always referred to as $I^2 R$ losses? Here is my problem. If the power coming from a power station is fixed then you can either deliver this power as high voltage, low current or high current, low voltage. But isn't $I^2R$ equal to $V^2 / R$, therefore if R is constant doesn't the power depend on the square of the voltage so surely it doesn't matter whether it is high voltage or high current. The only way I can reconcile this is that a high current must cause a greater heating effect than a high voltage. I can't figure why though. If this is the case then is there a reason why a high current causes more heating than a high voltage? I'd like to modify the names used to typeset some of my document elements. For example, the caption of figure floats should change from "Figure" to "Fig.", and my \tableofcontents sectioning heading shouldn't read "Contents", but "Table of Contents". How can I do that?  \documentclass{article} % \usepackage[english]{babel} \begin{document} \tableofcontents \section{foo} \begin{figure}[h] \centering \rule{1cm}{1cm}% placeholder for graphic \caption{A figure} \end{figure} \end{document} LINK : fatal error LNK1104: cannot open file 'D:\...\MyProj.exe' Prove equation with binomial coefficient Specific derivatives have specific names. First order is often called tangency/velocity, second order is curvature/acceleration. I've also come across words like Jerk, Yank, Jounce, Jolt, Surge and Lurch for 3rd and 4th order derivatives. Is there a widely agreed list of names for these? How many orders have specific names?  In this case, I'm dealing with NURBs curves, so the "tangency" and "curvature" related words are to be preferred over "velocity" and "acceleration" words. Post Problem Analysis - Rod in a cylindrical time varying magnetic field? A metal rod of length $l$ is placed (as shown in figure) in a cylindrical time varying magnetic field. Find the potential difference across it.   My answer:  As electric fields as forming circles around the centre with magnitude $$\frac12r\frac{dB}{dt}$$ whose magnitude is same along any chord at a fix distance from centre: $$\Delta V=E.l=\frac12r\frac32at^{\frac12}.l$$ $$\Delta V=\frac34arlt^{\frac12}$$  My question: Is $\Delta V =V_M-V_N$ or $\Delta V=V_N-V_M$ $\bf OR$ equivalently which side is at high potential?  Possible    $(i)$ As Field lines are circular from $M$ to $N$, $M$ must be high potential. $(ii)$ As this field line apply a force on electrons- in the rod- towards left, then $M$ must have excess $e^-$ and $N$ must have deficiency; so $N$ would be high potential as $M$ is $(+)$ and $N$ is $(-)$. Elantech Touchpad not working on Ubuntu 16.04 and Arch Linux So I have and Asus R558UF notebook with an Elantech Touchpad. After installing Ubuntu 16.04, the touchpad worked once but after restarting, it failed to work and has not been working ever since.  This is output of xinput:   ↳ Elan Touchpad                            id=12   [slave  pointer  (2)]   In Mouse and Touchpad settings, the touchpad is enabled. What should I do to fix this? Sarrus Rule with LaTeX Is there a way to create a new command with 9 arguments ({a_{11}},{a_{12}},{a_{13}},{a_{21}},{a_{22}},{a_{23}},{a_{31}},{a_{32}},{a_{33}}) that has as output a matrix with the Sarrus Rule? For instance: to obtain     just use the command that we will call sarrus:  \sarrus{-k}{k-1}{1}{0}{k-1}{k}{2}{0}{1}.   If it is possible i want to use the command sarrus in math mode just like matrix for istance. Is it safe to use file's hash as IV? I'm encrypting some files using AES in CBC mode.    I'm also using file's digest (SHA-1) to check that data is decrypted correctly (so I need to store it with file).  Is it safe to use this digest as AES's IV and store it in the header of file? Or it has security issue? Will stationary charge radiate E.M waves if observer is accelerating? I've been perusing the internet looking for interesting problems to solve. I found the following problem and have been going at it for the past 30 minutes with no success:     Find a function $f: \mathbb{R} \to \mathbb{R}$ satisfying $f(f(x)) = -x$ for all $x \in \mathbb{R}$.   I am also wondering, can we find $f$ so that is continuous?  I was thinking of letting $f$ be a periodic function, and adding half the period to x each time. I had no success with this, and am now thinking that such a function does not exist.  Source: Excel automatic hyperlinks An awful lot of people seem to use the phrase "substitute X for Y" to mean "replace X with Y", while I've always used and understood it as "replace Y with X". This makes sense to me, given that a substitute is the replacement, not the thing which has been replaced.  I thought I might be able to figure things out from a dictionary, but now after seeing two sorts of definitions, I'm even more confused:   to put or use in the place of another to take the place of; replace   The first one suggests that the object will be the substitute (replacement), the thing put into place, while the second suggests that the object will be the thing which has been replaced.  Is one of these usages more correct in any sense? (I know this is probably a pointless question, since people will continue to speak the way they speak.) Is there perhaps a difference between American and British English?   And most importantly, is there any reliable way to tell what someone means when they ask how to substitute honey for sugar, or is the verb simply guaranteed to cause confusion? Do different databases use different name quote? For example, mysql quote table name using   SELECT * FROM `table_name`;   notice the `   Does other database ever use different char to quote their table name How do I know if food left at room temperature is still safe to eat? Suppose you had a question, and you really want a good answer that would solve your problem, but noticed it was already asked by someone else. However, no one has posted any answers. The question is technically considered "unanswered", but a lot of users who would otherwise bother to give a correct answer probably skip the question completely for some reason.  What should I do in this case?  One idea is to ask a new, completely identical question, in the hope users will notice the new question and post an answer there. But would that go against SE policy?     Note: This is adapted from , but that doesn't cover the case where the original question is unanswered. Also, it is not a duplicate of , as that question asks about getting attention for one's own questions, while this one and the one linked above ask about getting an answer if someone else has already posted the same thing. I have six upvotes for the one question with no intervening history. They have been summarised into two groups - one with 4 events and one with 2 events. However, when you expand either, both show all 6 events. Minor I know, just letting you know. change terminal title I want to make a shell alias that starts a certain program and also changes the title of the terminal to the name of the program.  How can I do that?  In case it matters, I am running the terminal on Ubuntu and connecting to a Debian server via ssh. If two functionals have the same kernel, then one is a multiple of the other I would like some help with this exercise.  Suppose that $f_1,\ f_2 \in V^*$ and that $\text{Ker} f_1 = \text{Ker} f_2$. Show that $f_1 = k f_2$ for some scalar $k$.  I expect your suggestions.  Thanks!