How do you get installed software like sound recorder to open for use when playing sound or music? For that matter how do get access, like on desk top for any installed software to display icon for use? If this is old question please direct me, new to Ubuntu.
Just installed Ubuntu for the first time... Is there any simple way to browse installed programs?  On Mac there is the Applications top-level folder... here I see Desktop, Documents, Downloads etc but no Apps? That'd be a good idea, no? (is there some way to create this myself?)  On Windows there is the Start menu...  Here it seems like I have to click the 'Dash Home' and then I can see 'Recent Apps' ... I can search for them (I'd rather not)  ...or I can click the ruler/pencil icon at the bottom and see 'Recent Apps' and click to expand 'Installed Apps' ...ok that's all of them - is it possible to get a straight list view instead of the hard-to-scan wrapped rows?  Also, is there any way to get rid of the pointless random selection of 'Apps available for download' at the bottom?
Way to go from recursion to iteration I've used recursion quite a lot on my many years of programming to solve simple problems, but I'm fully aware that sometimes you need iteration due to memory/speed problems.  So, sometime in the very far past I went to try and find if there existed any "pattern" or text-book way of transforming a common recursion approach to iteration and found nothing. Or at least nothing that I can remember it would help.   Are there general rules? Is there a "pattern"? Matching exact string with JavaScript How can I test if a RegEx matches a string exactly?  var r = /a/; r.test("a"); // returns true r.test("ba"); // returns true testExact(r, "ba"); // should return false testExact(r, "a"); // should return true How to perform hard / cold reboot of iPhone or iPad? Show only hidden files (dot files) in ls alias How can I generate isometric sprite sheets from 3D animations? As we know, the tactical downvoting (I'm talking especially about SO, as I don't know about other sites) is more and more becoming a serious problem, as I see, the community can't stop this behavior without some sacrificing.  As a suggestion, I think it makes sense to prevent an answerer from downvoting any answer on the same question, this -sure- has a harm, but IMO, it's less harmful than the tactical downvoting issue, and to make the things a bit more easier, we can prevent an answerer from downvoting a question without posting a comment to that answer before.  And vice versa, if a user downvoted an answer, he shouldn't be able to post another one unless he posted a comment first, to prevent working-around that system, so a user can't downvote other answers before posting his own to avoid posting comments.  EDIT, more clarification: I don't say wrong answers shouldn't be downvoted, BUT if you want to downvote an answer and post your own, you'll have to post a comment, so we make sure you're not just downvoting right answers tactically. I'm reading a proof about Lagrangian => Hamiltonian and one part of it just doesn't make sense to me.  The Lagrangian is written $L(q, \dot q, t)$, and is convex in $\dot q$, and then the Hamiltonian is defined via the Legendre transform  $$H(p,q,t) = \max_{\dot q} [p \cdot \dot q - L(q, \dot q, t)]$$  Under the right conditions there exists a function $\dot Q (p,q,t)$ such that  $$H(p,q,t) = p \cdot \dot Q(p,q,t) - L(q, \dot Q(p,q,t), t)$$  i.e. when some $\dot Q(p,q,t)$ satisfies $p = \frac{\partial L}{\partial \dot q}\rvert_{(q, \dot Q(p,q,t), t)} = \frac{\partial L}{\partial \dot q}(q, \dot Q(p,q,t), t)$  (Finding this function is usually called "inverting p")  By taking partials in the $p$ variable and using the relationship, we can obtain the relationship  $$\dot Q = \frac{\partial H}{\partial p}$$  Because of the notation I chose, I get the strong urge to say $\dot q = \frac{\partial H}{\partial p}$  , and in fact this is what the textbook does. But have we proved this?    In other words, how can we deduce that  $$q'(t) = \frac{\partial H}{\partial p}(p(t), q'(t), t)$$ for any differentiable vector valued function $q$? (or maybe there are more conditions we need on $q$? Here  $$p(t) = \frac{\partial L}{\partial \dot q}(q(t), q'(t), t)$$ according to Lagrange's equations. The $n$ complex $n$th roots of a complex number $z$ Keep box-shadow direction consistent while rotating Using expect for inputting commands Heres the thread I'm bouncing off of:   So I'm trying to run this command: cd /etc/openvpn/easy-rsa; . ./vars; ./build-key username  However, after running that command, I need to input nothing [just press enter] 10 times, and press y twice. The user on the last thread suggested I use except, but I couldn't get it working. Here are the questions it asks:  root@suffice-vpn:/etc/openvpn/easy-rsa# ./build-key usernamtest Generating a 2048 bit RSA private key ..................+++ ........+++ writing new private key to 'usernamtest.key' ----- You are about to be asked to enter information that will be incorporated into your certificate request. What you are about to enter is what is called a Distinguished Name or a DN. There are quite a few fields but you can leave some blank For some fields there will be a default value, If you enter '.', the field will be left blank. ----- Country Name (2 letter code) [US]: State or Province Name (full name) [NY]: Locality Name (eg, city) [Merrick]: Organization Name (eg, company) [IceWare]: Organizational Unit Name (eg, section) [IceWare]: Common Name (eg, your name or your server's hostname) [usernamtest]: Name [server]: Email Address [iceware@programmer.net]:  Please enter the following 'extra' attributes to be sent with your certificate request A challenge password []: An optional company name []: Using configuration from /etc/openvpn/easy-rsa/openssl-1.0.0.cnf Check that the request matches the signature Signature ok The Subject's Distinguished Name is as follows countryName           :PRINTABLE:'US' stateOrProvinceName   :PRINTABLE:'NY' localityName          :PRINTABLE:'Merrick' organizationName      :PRINTABLE:'IceWare' organizationalUnitName:PRINTABLE:'IceWare' commonName            :PRINTABLE:'usernamtest' name                  :PRINTABLE:'server' emailAddress          :IA5STRING:'iceware@programmer.net' Certificate is to be certified until Jan 14 18:27:48 2026 GMT (3650 days) Sign the certificate? [y/n]:y   1 out of 1 certificate requests certified, commit? [y/n]y   As you can see, I press enter 8 times initially [to keep the default input] and then press enter another 2 times to skip the optional commands. Then, I need to press y twice. How can I automate this? I need to have this all happen in one command. Any suggestions? Thanks in advance. Can we implement the low quality flags to delete posts after a certain number of flags? Can we implement the low quality flag to be like the abuse or spam flags. So if a certain number of low quality flags are made  on a post (whether it be a questions or an answer) the post is deleted?  This would also relieve *close vote and delete vote queues. *which is a much discussed topic.        related: Does anyone know how to remove this dead bolt that has no screw heads to use a screw driver? Here's a picture below. The weighted sum of two independent Poisson random variables Using wikipedia I found a way to calculate the probability mass function resulting from the sum of two Poisson random variables. However, I think that the approach I have is wrong.  Let $X_1, X_2$ be two independent Poisson random variables with mean $\lambda_1, \lambda_2$, and $S_2 =  a_1 X_1+a_2 X_2$, where the $a_1$ and $a_2$ are constants, then the probability-generating function of $S_2$ is given by $$ G_{S_2}(z) = \operatorname{E}(z^{S_2})= \operatorname{E}(z^{a_1 X_1+a_2 X_2}) G_{X_1}(z^{a_1})G_{X_2}(z^{a_2}). $$ Now, using the fact that the probability-generating function for a Poisson random variable is $G_{X_i}(z) = \textrm{e}^{\lambda_i(z - 1)}$, we can write the probability-generating function of the sum of the two independent Poisson random variables as $$ \begin{aligned} G_{S_2}(z) &amp;= \textrm{e}^{\lambda_1(z^{a_1} - 1)}\textrm{e}^{\lambda_2(z^{a_2} - 1)}  \\ &amp;= \textrm{e}^{\lambda_1(z^{a_1} - 1)+\lambda_2(z^{a_2} - 1)}. \end{aligned} $$ It seems that the probability mass function of $S_2$ is recovered by taking derivatives of $G_{S_2}(z)$ $\operatorname{Pr}(S_2 = k) = \frac{G_{S_2}^{(k)}(0)}{k!}$, where $G_{S_2}^{(k)} = \frac{d^k G_{S_2}(z)}{ d z^k}$.  Is this is correct? I have the feeling I cannot just take the derivative to obtain the probability mass function, because of the constants $a_1$ and $a_2$. Is this right? Is there an alternative approach?  If this is correct can I now obtain an approximation of the cumulative distribution by truncating the infinite sum over all k? How do you prevent an ENTER key press from submitting a form in a web-based application? Trying to remember a book about a human male travelling to alien planet How can I recover a deleted file on Android? I just deleted a file on my Nexus S that I really need back. (It was actually part of an app using a sqlite database that did a drop table when upgrading to a new version.)  Presumably I need to root the phone first (which I hear is easy on Nexus phones) but am I in a catch-22 here? Namely, does rooting the phone mean wiping/overwriting the partition where the data lives?  If not, what do you recommend for data recovery tools? Presumably the file was just unlinked and not actively overwritten (per usual when "deleting" a file) so technically the data must be there... How much memory can a 32 bit process access on a 64 bit operating system? How to make an ImageView with rounded corners? How do I delete multiple rows in Entity Framework (without foreach) How can I remove Amazon search results from the dash or disable the feature? How can I disable Amazon search results in the Dash?