I'm trying to make a program that will take a file, say my_test_file.log and make a new file called my_test_file.mdn. I'd like to be able to use this program by typing python renameprogram.py my_test_file.log into the command line. The original file will always end in .log.
Is there a function to extract the extension from a filename?
Is there a rule forbidding the use of “is” at the end of a sentence? Is there any justification for using “is” at the end of an English sentence, or is there a rule that forbids this? A   B   C   D   E   F             I don't even know. It just seemed weird.  Yes, I understand I could just avoid doing something like that. But the problem already exists with a single level.   Consider having 2 images in a post. Both exceed the maximum width of a post. One is nested in a list. Key to this issue is that my original images were much larger. They were automatically resized.  Image    List      I think it looks weird. I'm assuming that the answer to the question in the title is a resounding yes. Since Baryonic matter and dark matter interact via gravitational forces.  If this is the case how is information not lost if, as is presumed, dark matter does not interact via the electromagnetic force? Intellisense in IntelliJ no longer working How do I perform an IF...THEN in an SQL SELECT? How do I perform an IF...THEN in an SQL SELECT statement?  For example:  SELECT IF(Obsolete = 'N' OR InStock = 'Y' ? 1 : 0) AS Saleable, * FROM Product How can I make sure that only low and medium security inmates are in a specific area? Is it possible to reverse the overlay you can set? It seems like you are only able to clear areas for low OR medium security prisoners, but sharing is not possible. The thing I want here is to make sure that max security prisoners are not in certain areas. $\sigma$-algebra vs. $\sigma$-field: is there any difference? The subject says it all: is there any difference between the two concepts of $\sigma$-algebra and $\sigma$-field? In probability theory, they seem to be used more or less interchangeably. If there is no difference, is there any historical reason why some people/schools use the term $\sigma$-algebra, while others use the term $\sigma-$field? On the existence of a continuous bijection $f\colon [0,1]\to [0,1]\times [0,1]$ Let $f$ be a continuous function on $[0,1]$ such that $f([0,1])=[0,1]\times[0,1].$ Then show that $f$ is not one-one.  Hints will be appreciated. Did Dolores Umbridge Have Any Association with Voldemort (or Death Eaters) before His Return? I noticed that Dolores Umbridge was born during the first Wizarding War, so it's very likely she wasn't a Death Eater then (but she is pretty evil -- who knows?).  After that Voldemort was not around in a way that could affect many people, and most wouldn't know he was planning to rise again.  During that time, and up through Voldemort's return (in Goblet of Fire), did Umbridge have any connection with the Death Eaters or with Voldemort?  Was she doing what she did on her own, or was it because of an association with Voldemort or his allies? How do I add a Pokestop to my area? How do I add a Pokestop to an area that has none? It is an area where there are tons of businesses but unless I drive about a mile from my work area there are no Pokestops.   I want to add one since we have 1000's of people in the work area, a lot of them play Pokemon Go, and we all can't leave work to drive a mile away to get to a Pokestop area.   Plus it would be nice to be able to capture Pokemon on our breaks. What does this pen notation in my UK entry stamp mean? I entered the UK from Paris once (riding the Eurostar train), and after the UK border control officer placed an entry stamp in my passport, he added a notation in pen (picture below).  What does it mean?  I suspect it is some sort of "warning" (the border control officer was not happy with me, though thankfully did not refuse entry).  I've always been curious about what it means more precisely or whether my prediction is even correct.  I've entered the UK only once again after getting this stamp.  I was admitted then too, but it took a while (the border control officer went away for about 10 minutes to do something before letting me in). How to use 1. (number followed by dot) format instead of [1] format in bibliography This is the proof, which I mostly understand except for one bit:  You have $h_1 \in H_1$ and $h_2 \in H_2$.   We also have $h_1^{-1}(h_2^{-1}h_1h_2) \in H_1$, because $h_2^{-1}h_1h_2 \in h_2^{-1}H_1h_2 = H_1$. Similarly, we have $(h_1^{-1}h_2^{-1}h_1)h_2 \in H_2$. Therefore  $$ h_1^{-1}h_2^{-1}h_1h_2 \in H_1 \cap H_2 = \{1_G\} $$  and so $h_1^{-1}h_2^{-1}h_1h_2 = \{1_G\}$. Let's first multiply everything on the left by $h_1$  $$h_1^{-1}h_2^{-1}h_1h_2 = \{1_G\}$$ $$ h_1 h_1^{-1}h_2^{-1}h_1h_2 = h_1 \{1_G\}$$ $$ h_2^{-1}h_1h_2 = h_1 \{1_G\}$$   Multiply both sides on the left by $h_2$ giving us  $$ h_1h_2 = h_2 h_1 $$  The bit I don't get is right at the beginning. Why is this correct: "We also have $h_1^{-1}(h_2^{-1}h_1h_2) \in H_1$, because $h_2^{-1}h_1h_2 \in h_2^{-1}H_1h_2 = H_1$." minimal polynomial of powers of a matrix I am wondering, given the minimal polynomial of $A$, what can we say about the minimal polynomial of $A^n$?  I know that if we were looking at the roots of the characteristic polynomial ie eigenvalues then the roots of the characteristic polynomial of $A^n$ would be $nth$ powers of the eigenvalues so again these are roots of the minimal polynomial also. Algorithms for computing multiplicative order modulo $n$ Linux command line. Move all files and directories in directory, except some files and directories Copying unicode symbols from Firefox address bar as is Let's say I open a webpage with some Unicode characters, say, Cyrillic, in the address like this:        When I try to copy it from the address bar somewhere else, it becomes unreadable rubbish:        I guess this is for compatibility. However for readability I want to copy it straight away with proper Unicode characters.  What and how should I tweak to make that possible?  Edit: The answers are good, but they are hacky. Are there any settings in about:config? Where to find cross section data for $e^{-}$ + $p$ $\longrightarrow$  $p$ + $e^{-}$ ?  does not include it. In PHP (>= 5.0), is passing by reference faster? In PHP, function parameters can be passed by reference by prepending an ampersand to the parameter in the function declaration, like so:  function foo(&amp;$bar) {     // ... }   Now, I am aware that this is not designed to improve performance, but to allow functions to change variables that are normally out of their scope.  Instead, PHP seems to use Copy On Write to avoid copying objects (and maybe also arrays) until they are changed. So, for functions that do not change their parameters, the effect should be the same as if you had passed them by reference.  However, I was wondering if the Copy On Write logic maybe is shortcircuited on pass-by-reference and whether that has any performance impact.  ETA: To be sure, I assume that it's not faster, and I am well aware that this is not what references are for. So I think my own guesses are quite good, I'm just looking for an answer from someone who really knows what's definitely happening under the hood. In five years of PHP development, I've always found it hard to get quality information on PHP internals short from reading the source. Zero divisor in $R[x]$ Let $R$ be commutative ring with no (nonzero) nilpotents. If $f(x) = a_0+a_1x+\cdots+a_nx^n$ is a zero divisor in $R[x]$, how do I show there's an element $b \ne 0$ in $R$ such that $ba_0=ba_1=\cdots=ba_n=0$?