I've recently stumbled across an explicit constructor that receives a single pointer argument. I wonder if the explicit keyword is necessary in this case? as there is no constructor for a pointer so there cannot be any implicit conversion.  class Foo {  public:   explicit Foo(int* int_ptr); }
What does the explicit keyword mean in C++?
When I apply a glossy shader to the material of my text, the text becomes just black. Why?    I have lamp and everything, but the problem persists. The text is red before I add the glossy shader.  I'm using Cycles render.   Thanks! Combine and Minify Multiple CSS / JS Files Should questions include "tags" in their titles? I've seen questions edited to remove the language name from the title. Won't search engines - and folks using search engines - have an easier time finding them if these "tags" are kept as part of the title? Is volunteer work allowed in the US while visiting under the VWP or a B1/B2 visa? I am going to Santa Monica for 4 weeks to polish my English in July and would like to volunteer at the Planetary Society located in Pasadena.  I am a Swiss citizen and have a biometric passport. However, I don't have any special visa, as there is no visa needed for the school I am attending and using the Visa Waiver Program, I am allowed to stay up to 90 days in the US.  Am I allowed to do volunteer work during my stay? In Windows there is a straightforward "Format" option in a flash drive's right-click pop-up menu. Where's that in Ubuntu? Is there a term for someone who "can see multiple perspectives"? A colleague of mine is trying to describe herself as "capable of seeing a situation from multiple perspectives" or "able to look at the big picture from various viewpoints". I feel like there must be a better way to get this point across.  Is there a more concise way to describe this characteristic? Polygamma function series: $\sum_{k=1}^{\infty }\left(\Psi^{(1)}(k)\right)^2$ Applying the , I found: $$S=\displaystyle\sum_{k=1}^{\infty }\left(\Psi^{(1)}(k)\right)^2\lt\dfrac{2}{3}\pi^2$$ where $\Psi^{(1)}(k)$ is the polygamma function. Is it known any sharper bound for the sum $S$? Thanks. F# insert/remove item from list Why ; is called semicolon and what is its history? Semi- is a Latin prefix meaning "half" and colon is another punctuation. Should I therefore say that semicolon is a halved colon? Let $f \in C [a,b]$ such that $\forall x\exists y$ such that $|f(y)| \leq \frac{1}{2}|f(x)|$. Prove that $\exists c\in [a,b]$ such that $f(c) = 0$. Why are there hexagonal holes in my donut? I'm currently making a donut using blender gurus tutorial. I have no idea why, but there are holes in my icing. Does anyone know what could be causing it? Thanks for any help. The volume "filesystem root" has only 0 bytes disk space remaining? Does someone knows if it exists some ppa packages source for the newest Ubuntu version 19.10 i had problem with that when i upgraded from Ubuntu 19.04 to 19.10 i didn't work? Why and how is the speed of light in vacuum constant, i.e., independent of reference frame? I was told that the Galilean relative velocity rule does not apply to the speed of light. No matter how fast two objects are moving, the speed of light will remain same for both of them.   How and why is this possible?   Also, why can't anything travel faster than light? Does anyone know of a nice (and preferably free) way to integrate Prolog and C#?  Im looking to create a Prolog dll or similar to call from my managed code, and retrieve an answer once all the processing has been complete. Im looking for it to be predominantly one sided (c# calls Prolog).  I have seen  which talks about Prologs real world usage but I was wondering if anyone had either any experience with c# &amp; Prolog? or a nice tutorial/article? Finding minimum-area-rectangle for given points? I went through a , but the answer was informing how to hide the monitor, but not how to disable it. I do not want any new windows to creep into the laptop display when the external display is connected. I could not find any in the Display Settings (under System Preferences). I don't want to close the lid because I think it impacts the air flow of the MacBook Pro. I don't want to close the lid because the sound quality is reduced. Cardinality of the quotient ring $\mathbb{Z}[x]/(x^2-3,2x+4)$ This problem is from a practice exam I was working on.     What is the cardinality of the quotient $\mathbb{Z}[x]/(x^2-3,2x+4)$ ?   Thoughts. If I find a ring that is easier to handle then this then I can go from there. So I think this is isomorphic to $\mathbb{Z}_2[x]/(x^2-3,x+2)$. And then I am stuck.  Am I correct so far? What should I be looking to do from here?  Thanks for your time and your answers. What is the optimum button size of touch screen applications? There was a not so recent blog post about the ideal button size of touch screen control sizes (sorry there is no link, the website is now a spam trap) that was based on the  form the MIT touch lab that gives some measures of the size and sensitivity of the finger. If found that averages for finger pads are between 10–14mm and fingertips are 8–10mm. This would make 10mm x 10mm a good minimum touch target size.  As the author of the blog pointed out, this ideal contact size is much larger than the suggested size for Windows and Apple devices that is in their design guides. I am wondering why there is such a difference, and whether it makes more sense to increase the size of controls on touch screen applications, or if this is not really a usability issue at all? Also, it seems that many mobile websites and apps seem to completely ignore these principles. I am sure the screen size poses a limitation to how big the interface controls can be, so is this simply a trade-off between being able to fit in as much information versus how easy it is to interact with the control? It feels as if the stylus is not something that is in much use. A similar question has been raised on the minimum/smallest size that you can get away with, but I would consider this to be a different question to what the optimum size should be, because the smallest size accommodates the minimum usability requirement, whereas the optimum size caters for the best usability requirement. Archived link of the blog (original domain shows spam)  And here is another reference it to (just to show that it is not the problem with the link but the website () UPDATE #1: another new reference that has a very precise figure of a minimum of 44 x 44 points, not sure how it is derived exactly but interesting (). Read Section 2. Provide Large Clickable Elementss. UPDATE #2: another reference, this time from  citing touch target size to 9 mm square or greater (48x48 pixels on a 135 PPI display at a 1.0x scaling plateau). They also suggest avoid using touch targets that are less than 7 mm square. UPDATE #3: something from the  that I referenced recently citing 44 x 44 points. UPDATE #4: NN/g has published an article on  and the information/conclusion remains unchanged. UPDATE #5 A really nice write-up on the need to enhance the  of common UI elements, citing the  that the &quot;minimum target size for touch or mouse should be 44×44 pixel&quot; (2.5.5 - Target Size - Level AAA). How do I clone a single branch in Git?