Problem with citing in biblatex, document just shows the citation key
Question mark or bold citation key instead of citation number
Evaluate this power series Evaluate the sum  $$x+\frac{2}{3}x^3+\frac{2}{3}\cdot\frac{4}{5}x^5+\frac{2}{3}\cdot\frac{4}{5}\cdot\frac{6}{7}x^7+\dots$$  Totally no idea. I think this series may related to the $\sin x$ series because of those missing even powers. Another way of writing this series:  $$\sum_{k=0}^{\infty}\frac{(2k)!!}{(2k+1)!!}x^{2k+1}.$$ Is there anything in the physics that enforces the wave function to be $C^2$? Are weak solutions to the Schroedinger equation physical? I am reading the beginning chapters of Griffiths and he doesn't mention anything. How to get the valid URL of a Link field from within a Twig template? I have a Link field named field_my_link (machine name).  Within a Twig template I can get the link's URL value with this:  {{ node.field_my_link.uri }}   If inside the Link's URL there is an external URL, e.g. http://example.com it works good.  But, if inside the Link's URL there is stored an internal URL, e.g. "/node/11", I get a value like this:  "internal:/node/11"   with the "internal:" prefix.  How can I get the valid URL?  For example, if the link's URL is "http://example.com" I want "http://example.com" (this already works), if the link's URL is "/node/11" I want the relative URL "/node/11", if the link's URL is "&lt;front&gt;" I want the URL "/", etc.    EDIT  I can get the value I want within a PHP preprocess function, using this:  $url = $variables['node']-&gt;get('field_my_link')-&gt;first()-&gt;getUrl();   How can I access the same value within the Twig template?  I know I can do this within the preprocess function:  $variables['my_url'] = $url;   Then access the url within Twig using {{ my_url }}, but I would avoid to write a preprocess function each time I have a link field. Getting key with maximum value in dictionary? I have a dictionary: keys are strings, values are integers.  Example:   stats = {'a':1000, 'b':3000, 'c': 100}   I'd like to get 'b' as an answer, since it's the key with a higher value.  I did the following, using an intermediate list with reversed key-value tuples:  inverse = [(value, key) for key, value in stats.items()] print max(inverse)[1]   Is that one the better (or even more elegant) approach? How do I remove objects after building them, for example a fence that I placed without taking into account its orientation? I have right clicked on it like you would a structure but nothing happened. I have also tried Shift+Alt+Click and nothing has happened. I couldn't think of any other solutions as this is my first game. Horizontal line of custom length like an — Is there a way to get a custom-length horizontal line that appears like a "longer em-dash", if you will? I have a query going that gets data for an ID for the last 3 months.  I need to tweak it so I get the highest value for each of the three months.  I've tried a couple of things with the aggregate function MAX, but I'm not getting anywhere.  I'm trying to get the max value for each of the past months ....  Here's the data from the query, currently sorted by date (asc):   ID      Date               Value 12410   01/03/2017 12:17    0.000178 12410   01/10/2017 11:36    0.000186 12410   01/17/2017 11:27    0.000189 12410   01/24/2017 13:09    0.000182 12410   01/31/2017 10:37    0.000169 12410   02/07/2017 11:03    0.000214 12410   02/14/2017 11:52    0.000176 12410   02/21/2017 10:51    0.000200 12410   02/28/2017 12:29    0.000194 12410   03/07/2017 08:39    0.000206   Here's the query:   select AnalysisID as "ID" , AnalysisDateTime as "Date", AnalysisValue as "Value" from AnalysisValueTbl where AnalysisID = 12410 and DatePart(m, AnalysisDateTime) = DatePart(m, DateAdd(m, -3, getdate())) and DatePart(yyyy, AnalysisDateTime) = DatePart(yyyy, DateAdd(m,-3, getdate())) or AnalysisID = 12410 and DatePart(m, AnalysisDateTime) = DatePart(m, DateAdd(m, -2, getdate())) and DatePart(yyyy, AnalysisDateTime) = DatePart(yyyy, DateAdd(m,-2, getdate())) or AnalysisID = 12410 and DatePart(m, AnalysisDateTime) = DatePart(m, DateAdd(m, -1, getdate())) and DatePart(yyyy, AnalysisDateTime) = DatePart(yyyy, DateAdd(m,-1, getdate())) order by AnalysisValue desc How can I send mail from an iPhone application Prove that the expression cannot be a power of 2 Integral $\int\frac{dy}{(y^2 + ay + b)^{3/2}}$ Need the indefinite integral with $a,b$ constants. This is not a homework question. Need it for a physics problem. What if the answers of a historical locked question become obsolete? Hint:  $a^2 -ab +b^2 = (a+b)^2 -3ab.$  I know we can say that there exists an $x,y$ such that $ax + by = 1$.  So in this case, $(a+b)x + ((a+b)^2 -3ab)y =1.$  I thought setting $x = (a+b)$ and $y = -1$ would help but that gives me $3ab =1.$  Any suggestions? I have a script myscript.sh  #!/bin/sh  echo $1 $2   which is used something like ...  ./myscript.sh foo bar   which gives me an output of ...  foo bar     but how can i make this script include custom command options? for example ...  ./myscript.sh -a foo and corespond to $1   and  ./myscript.sh -b bar and corespond to $2 Suppose $f:X\rightarrow Y$ is a surjection and you want to show that there exists $g:Y\rightarrow X$ s.t. $f\circ g=\mathrm{id}_Y$. You need the AC to show this.  However, suppose $f$ is a injection and you want show there is $g$ s.t. $g\circ f=\mathrm{id}_X$. Then, according to my textbook, you don't need the AC to show this.  This is counterintuitive to me, because it's like you need a special axiom to claim that an infinite product of big sets is nonempty, while you don't need one to claim that an infinite product of singleton sets is nonempty, which seems smaller than the former.  So why don't you need the AC to show the latter?  EDIT: $X$ should be nonempty.  EDIT 2: I realized (after asking this) that my question mostly concerns whether the AC is needed to say that an infinite product of finite sets is nonempty, and why. My understanding is that GPUs are more efficient for running neural nets, but someone recently suggested to me that GPUs are only needed for the training phase. Once trained, it's actually more efficient to run them on CPUs.  Is this true? What makes matter travel along geodesics? The relativistic explanation of gravity is geometric, the motion of a body in a field of space-time distortion can be described as being at rest and travelling along a geodesic of that field, but why does it travel along that geodesic? What causes it to move? How to get div height to auto-adjust to background size? How do I get a div to automatically adjust to the size of the background I set for it without setting a specific height (or min-height) for it? How can I solve this functional equation, where $x,y$ are any real numbers and $f:\mathbb{R}\to \mathbb R$ is a function such that : $$f(x+y)+f(x-y)=2f(x)\cos y$$    I tried substituting $x=0$ to get $f(y)+f(-y)=2f(0)\cos y$ . Taking $x=y$ gives $f(2x)+f(0)=2f(x)\cos x$. I similar get some more relations like that, but its not really helping me in finding anything useful. I also think the function must either be $\sin$ or $\cos$ looking at the product to sum formulae. Can anyone tell me how should I solve this? How many times can I benefit from Advantage if I attack multiple times while not seen? A hidden ranger with Extra Attack attacks a surprised creature. Do both attacks benefit from Advantage, or just the first one?  If the ranger used Horde Breaker on another creature, would this attack benefit from Advantage? Automatically login and lock