How can I change shell in Ubuntu?
How do I make Bash my default shell on Ubuntu?
My dad has an old Sears KS-2 + 50mm f/1.7, which from a bit of research seems to use a Pentax K-mount.  I've looked around a bit and found a , which says it supports af-confirmation, and costs ~$30 US.  Has anyone tried using an adapter ring like this, and if so, would you recommend doing so?  I am perfectly happy with shooting manual, but I'm curious about the quality of older lenses.  I'm assuming that if I use older primes the optical quality will be fine, and it looks like the build quality of the older lenses is much better that similarly priced new lenses. Does the Force wane as you age? @Valorum said     ...not to mention the sheer strain that comes from continually using the Force at an advanced age.   To my feeble mind, this doesn't make sense. Approaching 900 years old, Yoda is still as strong as any whippersnapper in terms of Force power and usage. Despite his old age, Obi Wan shouldn't have any problems with using his Force powers.  This got me to thinking, does the Force begin to leave you as you age? Is it a flow of Force power that goes down based on (I hate to say this) a decrease in midichlorian count as you approach your expiration date? ant deploy error - Maximum size of request reached I used to deploy metadata using ant migration tool successfully but from last night I am getting the below error:  John@John:~/mm_workspace/TEST_Project/deploy$ ant deployUnpackaged  Buildfile: /home/john/mm_workspace/TEST_Project/deploy/build.xml  deployUnpackaged:  BUILD FAILED /home/john/mm_workspace/TEST_Project/deploy/build.xml:72: Failed to submit request to https://cs19.salesforce.com/services/Soap/m/35.0/00D293456000Qaf for user john@test.com.dev. Error: {http://schemas.xmlsoap.org/soap/envelope/}Client - Maximum size of request reached. Maximum size of request is 52428800 bytes.  Total time: 2 minutes 10 seconds   I think this is because of too much metadata that I am trying to deploy. For now, I am deploying classes and then VF pages and so on but I am looking for an option to deploy everything in one go without running into the above error.  I am sure that people are working on more complex projects than mine with lots of metadata and I am wondering how are they deploying with out hitting this error?  Thanks Unmarshal a single element list fails Where is the ideal place to ask a MATLAB question? What method in the String class returns only the first N characters? chpasswd apply changes in the chroot directory Why are continuous functions the "right" morphisms between topological spaces? No Wifi, HP Pavillion 15 Ubuntu 14.04 How can I solve the following sequence Let we have the following sequence  $$y_n= \frac{1}{\sqrt{n^2+1}}+\frac{1}{\sqrt{n^2+2}}+\cdots+\frac{1}{\  \sqrt{n^2+n}}$$ find the limit of the sequence $y_n$ decide whether it is increasing or decreasing How will going from 75% Credit Utilization to 0% Credit Utilization affect my credit score? Relationship between (algebraic) vector bundle and (topological) vector bundle on $\mathbb{RP}^{1}$($\mathbb{P}^{1}$) I have build a website for a finance company.  The Cognito Form is on the website as an application form.  I would like the information sent automatically to the finance company's email address (as soon as the form is submitted) without having to log into Cognito Forms. The finance company needs to know the exact moment the application for finance comes in. The finance company can not possibly log in to Cognito Forms 24/7 to check if there are any finance applications. Find the functions $f:\Bbb R_*^+ \to \Bbb R_*^+$ such that:  $$f(x)f \left(\frac{1}{x}\right)=1$$ where do I use Database. Methods? I m trying to understand where we use following Database.Methods. I know if we want to insert a record to an object we use DML Statement. What i want to know is why/where we use Database. methods. It might be silly question. Database.saveResults Database.insert Database.query Database.Query Database.error   really appreciate the inputs. Thanks a ton in advance. How to get list of all sobject records modified today in the system? I need a list of all sobject records that got modified today. this is not just for one object but for all objects in the system. Is there a simpler way to do this? Suppose we have an object in space. say gravity is negligible, and the thing has a rocket on both sides. the thing fires one rocket for, say, 5 seconds. now it's moving. The object has kinetic energy. Now the other rocket fires for 5 seconds. Then it's stationary. where does the energy go? I know that some of the energy from the rockets would just go into space as heat and kinetic energy of the hydrogen particles flying out, but how does there seem to be more energy in the situation if the first rocket just goes for 10 seconds than if one goes for 5 and the other goes for 5? In Bishop's book "Pattern Classification and Machine Learning", it describes a technique for regularization in the context of neural networks. However, I don't understand a paragraph describing that during the training process, the number of degrees of freedom increases along with the model complexity. The relevant quote is the following:     An alternative to regularization as a way of controlling the effective   complexity of a network is the procedure of early stopping. The   training of nonlinear network models corresponds to an iterative   reduction of the error function defined with respect to a set of   training data. For many of the optimization algorithms used for   network training, such as conjugate gradients, the error is a   nonincreasing function of the iteration index. However, the error   measured with respect to independent data, generally called a   validation set, often shows a decrease at first, followed by an increase as the network starts to over-fit. Training can therefore be   stopped at the point of smallest error with respect to the validation   data set, as indicated in Figure 5.12, in order to obtain a network   having good generalization performance. The behaviour of the network   in this case is sometimes explained qualitatively in terms of the   effective number of degrees of freedom in the network, in which this   number starts out small and then to grows during the training process,   corresponding to a steady increase in the effective complexity of the   model.   It also says that the number of parameters grows during the course of training. I was assuming that by "parameters", it refers to the number of weights controlled by the network's hidden units. Maybe I'm wrong because the weights are prevented to increase in magnitude by the regularization process but they don't change in number. Could it be referring to the process of finding a good number of hidden units?  What's a degree of freedom in a neural network? What parameters increase during  training? How to get child process from parent process The event horizon of a black hole is where gravity is such that not even light can escape. This is also the point I understand that according to Einstein time dilation will be infinite for a far-away-observer.  If this is the case how can anything ever fall into a black hole.  In my thought experiment I am in a spaceship with a powerful telescope that can detect light at a wide range of wavelengths.  I have it focused on the black hole and watch as a large rock approaches the event horizon.  Am I correct in saying that from my far-away-position the rock would freeze outside the event horizon and would never pass it? If this is the case how can a black hole ever consume any material, let alone grow to millions of solar masses.  If I was able to train the telescope onto the black hole for millions of years would I still see the rock at the edge of the event horizon?  I am getting ready for the response of the object would slowly fade.  Why would it slowly fade and if it would how long would this fading take?  If it is going to red shift at some point would the red shifting not slow down to a standstill? This question has been bugging me for years!  OK - just an edit based on responses so far.  Again, please keep thinking from an observers point of view.  If observers see objects slowly fade and slowly disappear as they approach the event horizon would that mean that over time the event horizon would be "lumpy" with objects invisible, but not passed through?  We should be able to detect the "lumpiness" should we not through?