Want to build my own Ubuntu from source code
How to create a Customized Ubuntu Server ISO?
It seems that KNN is a discriminative learning algorithm but I can't seem to find any online sources confirming this.  Is KNN a discriminative learning algorithm? How much of an $n$-dimensional manifold can we embed into $\mathbb{R}^n$? I observed some naive examples. Spheres, for example, when we cut out one point, can be embedded into $\mathbb{R}^n$. And if we cut out a measure zero set of a projective space, it can be embedded into the Euclidean space of the same dimension. So I wonder if all manifolds can be embedded into a same dimensional Euclidean space when we cut out a measure zero set? Can anyone prove it or disprove it by giving me some counterexamples? Buffering in meters/km using WGS84 layers using QGIS I am using QGIS 1.7.4-Wroclaw and working with an SHP layer in WGS84. I want to buffer out to a certain number of kilometers from this layer using the ftools buffer tool.  I understand that the buffer tool always uses the layer units, which for WGS84 are decimal degrees. We all know that degrees don't convert consistently to meters, so how should I go about making my buffers?   Is it necessary for me to convert the shapefiles to a different CRS that natively uses meters?   If so, how do I choose one? Why does sudo change the PATH? I noticed that $f(x) = x\phi(x)$ seems to be one-to-one, where $\phi(x)$ is Euler's Phi function.  In particular, I'm writing some numerical python code and the line I have looks something like  sorted([n*phi(n) for n in range(1,1000)])   and there are no duplicates in the list.  First, is it one-to-one?  Second, if it is, is there a simple proof sketch? Nested cross validation for model selection How can one use nested cross validation for model selection?   From what I read online, nested CV works as follows:   There is the inner CV loop, where we may conduct a grid search (e.g. running K-fold for every available model, e.g. combination of hyperparameters/features) There is the outer CV loop, where we measure the performance of the model that won in the inner fold, on a separate external fold.    At the end of this process we end up with $K$ models ($K$ being the number of folds in the outer loop). These models are the ones that won in the grid search within the inner CV, and they are likely different (e.g. SVMs with different kernels, trained with possibly different features, depending on the grid search).  How do I choose a model from this output? It looks to me that selecting the best model out of those $K$ winning models would not be a fair comparison since each model was trained and tested on different parts of the dataset.  So how can I use nested  CV for model selection?   Also I have read threads discussing how nested model selection is useful for analyzing the learning procedure. What types of analysis /checks can I do with the scores that I get from the outer K folds? How do I disable client side decoration globally in GNOME? I'm using Ubuntu GNOME 17.04. One encounters client side decoration (CSD) as most of the official GNOME applications (Nautilus, gedit, Evince etc.) use  (a combined title bar and toolbar, see linked screenshots) whereas other applications don't. This feature is disabled in Unity, all the applications use traditional separate title bars.  Screenshots (from ):     Nautilus with GtkHeaderBar   Nautilus without GtkHeaderBar     For consistency I want to disable GtkHeaderBars globally (in all the applications using it) and use separate title bars. Is there a way to achieve that?  I have heard of gtk3-nocsd package, but couldn't make it work with GNOME for all the applications. Cannot find Background Images feature in Blender 2.8 Is the integral $\int_0^\infty \frac{\mathrm{d} x}{(1+x^2)(1+x^a)}$ equal for all $a \neq 0$? Let $a$ be a non-zero real number. Is it true that the value of $$\int\limits_0^\infty \frac{\mathrm{d} x}{(1+x^2)(1+x^a)}$$  is independent on $a$? Browsers redirect to level3.com if domain does not exist If I enter a URL incorrectly, my Firefox browser occasionally redirects me to    This occurs in Chrome too. I've restarted Firefox in safe mode, and it still happens I've restarted Windows 10 in safe mode, and it still happens I've installed Hitman Pro Alert. The scan found nothing, and could not prevent the redirect. My HOSTS file is clean. My ethernet settings IPv4 properties use Google's DNS: 8.8.8.8 and 8.8.4.4 The only other issue I have is when visiting  which produces numerous pop-up windows, unless I disable scripts. I have Comodo Internet Security (antivirus and firewall) installed, and it identifies nothing.   Any other suggestions? cant install or remove anything on 18.04 cause of DPKG error Why can we use sample variance of the treatment group to estimate population variance of the controls? get exact file create time windows 7 I'm trying to figure out exactly when I created a file. Windows 7 thinks I don't know how to subtract two times, and tells me it was created "1 hour ago." I need a little more detail than this, but I can't seem to find a setting to toggle this "feature" off.  Example below: no wifi in Ubuntu 15.04 I cannot see WiFi option in my Ubuntu 15.04. What should I do? Revert asap  lspci -nnk | grep 0280 -A2 output:-  03:00.0 Network controller [0280]: Qualcomm Atheros Device [168c:0042] (rev 30) Subsystem: Foxconn International, Inc. Device [105b:e09a]   rfkill list output:-  0: hci0: Bluetooth Soft blocked: no Hard blocked: no 1: acer-wireless: Wireless LAN Soft blocked: no Hard blocked: no      dmesg | grep ath [    9.545199] ath10k_pci 0000:03:00.0: pci irq msi-x interrupts 8 irq_mode 0 reset_mode 0 [   10.029684] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/cal-pci-0000:03:00.0.bin failed with error -2 [   10.029701] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/QCA9377/hw1.0/firmware-5.bin failed with error -2 [   10.029704] ath10k_pci 0000:03:00.0: could not fetch firmware file 'ath10k/QCA9377/hw1.0/firmware-5.bin': -2 [   10.029711] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/QCA9377/hw1.0/firmware-4.bin failed with error -2 [   10.029713] ath10k_pci 0000:03:00.0: could not fetch firmware file 'ath10k/QCA9377/hw1.0/firmware-4.bin': -2 [   10.029719] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/QCA9377/hw1.0/firmware-3.bin failed with error -2 [   10.029721] ath10k_pci 0000:03:00.0: could not fetch firmware file 'ath10k/QCA9377/hw1.0/firmware-3.bin': -2 [   10.029726] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/QCA9377/hw1.0/firmware-2.bin failed with error -2 [   10.029728] ath10k_pci 0000:03:00.0: could not fetch firmware file 'ath10k/QCA9377/hw1.0/firmware-2.bin': -2 [   10.029733] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/QCA9377/hw1.0/firmware.bin failed with error -2 [   10.029735] ath10k_pci 0000:03:00.0: could not fetch firmware (-2) [   10.029737] ath10k_pci 0000:03:00.0: could not fetch firmware files (-2) [   10.029739] ath10k_pci 0000:03:00.0: could not probe fw (-2) Which Harry Potter works are considered canon? Solving infinite sums with primes. Let $p_n$ denote the $n$'th prime number.  How would one go about proving that infinite products like: $$\prod_{k=1}^\infty1 - \frac{1}{(p_k)^2} = \frac{6}{\pi^2}$$  or  $$\prod_{k=1}^\infty\frac{{p_k}^2}{{p_k}^2 - 1} = \frac{\pi^2}{6}$$ are correct?  Is there any way to prove it except by exhaustion? How do i prove invertibility of this linear transformation Coffeescript existential operator sometimes checks against undefined, but not always Oven temperature for multiple ducks? I know I use them, and my peers use them, but how much does the average user actually use tooltips to figure out functionality?