Why is the int default value not taken during runtime?
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Why is the upper Riemann integral the infimum of all upper sums? I was reading the theory of Riemann integration when I cam across the following ,   If $f$ is bounded on $[a,b]$, and $P = \{x_0,x_1,x_2.......x_n\}$ is a partition of $[a,b]$, let $$M_j = \sup_{x_{j-1}\leq x\leq x_j}f(x)$$ The upper sum of f over P is $$S(P) = \sum_{j=1}^{n} M_j(x_j-x_{j-1})$$ and the upper integral of $f$ over $[a,b]$, denoted by $$\int_{a}^{b^-} f(x)dx$$ is the infimum of all upper sums.  The theorem similarly goes on to state the result for lower sums.  My doubt is : I do not understand how is $$\int_{a}^{b^-} f(x)dx$$ the infimum of all upper sums. I understand that if we refine the partition P, then the upper sum would decrease, so it may be a lower limit for all the upper sums computed on the refinements of P (but still being the lower limit does not prove that it is the infimum) and what about those partitions for which P itself is the refinement of?  How do I know that it will be a lower limit for those, let alone a infimum? I want to create a standalone python script using QGIS python API (PYQGIS) for education. First I create a model and export that model to python script.  original python script from the export :  ##=name ##raster=raster ##stat=output html outputs_QGISRASTERLAYERSTATISTICS_1=processing.runalg('qgis:rasterlayerstatistics', raster,stat)   Next I read this  and I tried to follow this tutorial to create my script.  Final script :  import sys from qgis.core import QgsApplication from PyQt4.QtGui import QApplication app = QApplication([]) QgsApplication.setPrefixPath("/usr", True) QgsApplication.initQgis()  # Prepare processing framework  sys.path.append('/home/username/.qgis2/python') from processing.core.Processing import Processing dem='aster.tif' slope='slope.tif' aspect='aspect.tif' outputs_SAGASLOPEASPECTCURVATURE_1=processing.runalg('saga:slopeaspectcurvature', dem,6,1,1,slope,aspect,None,None,None,None,None,None,None,None,None,None) Processing.initialize()  # Exit applications QgsApplication.exitQgis() QApplication.exit()   If I run this script it works fine without error but I don't take some export like aspect and slope (these can't be found?). Any idea why I can't take exports ?  I use Ubuntu and python 2.7 and QGIS 2.18.1.    i try to this script :  import sys from qgis.core import QgsApplication sys.path.append('/usr/share/qgis/python/plugins') import processing a=processing.alglist() print a processing.alghelp("saga:slopeaspectcurvature")   and i take that print any idea why ?  Algorithm not found   but if i use this module in QGIS work fine. Object emit light distance I created an object, and I wanted it to glow. I used to just place points of light around it, and parent them to it, but using the emit option in the materials seemed so much easier.  But when I gave it an a higher emit than 0, it went only a small distance before the light stopped. I turned it up to 200, and the object was white with light, but the light didn't go any farther. Oh and I changed the color, and nothing happened. Let $P$ be a probability measure on $(\Omega, \mathscr{F})$, If $a,b,\in\mathscr{F}$ and $A\subset B$, then $P(B)-P(A)=P(B\setminus A)\ge 0$.  So far I have:  $A\subset B \implies B\setminus A = B\cap A^c = \emptyset$ as $A$ and $B^c$ are disjoint. Since $A\cup (B\setminus A)=A\cup (B\cap A^c)=(A\cup B)\cap (A\cup A^c)=B\cap\Omega = B$  Then for $A,B\in \mathscr{F}\implies P(A\cup (B\setminus A))=P(A)+P(B\setminus A) = P(B)$ by countable additivity.  Rearranging, $P(B)-P(A)=P(B\setminus A) \ge 0$. Can we let users with privileges on one site have them on another? I have almost 4k reputation on Arqade. On Stack Overflow, I have to suggest edits and can't hit the close button. But I want to help with the close queue, which is at 62k at the time of this writing.  While I realize that people may be inexperienced with the system, I think I am experienced enough. If I want to edit something, I have to let it sit in the queue and get robo-reviewed. Yes, I know more about gaming than about coding. But I think I would know if this question is a duplicate of that, and if this question is off topic.  So, my request is that we should have the same privledges on every site, based on the site that we have the most reputation in. I am not asking that all the reputation be merged. Is there an app that will notify me (in notifications center) if a process is using up a high percentage of CPU for a specified amount of time? The other day, I was sitting in a coffee shop working, when I looked down to find that 25% of my battery was left.   I looked at my Activity Monitor and saw that the time machine process was going at 90% for a while (as long as I was watching it).   Are there any apps that can notify me if a process is at a certain level for a certain amount of time? Is there a simple way to flatten a list of iterables with a list comprehension, or failing that, what would you all consider to be the best way to flatten a shallow list like this, balancing performance and readability?  I tried to flatten such a list with a nested list comprehension, like this:  [image for image in menuitem for menuitem in list_of_menuitems]   But I get in trouble of the NameError variety there, because the name 'menuitem' is not defined.  After googling and looking around on Stack Overflow, I got the desired results with a reduce statement:  reduce(list.__add__, map(lambda x: list(x), list_of_menuitems))   But this method is fairly unreadable because I need that list(x) call there because x is a Django QuerySet object.  Conclusion:   Thanks to everyone who contributed to this question.  Here is a summary of what I learned.  I'm also making this a community wiki in case others want to add to or correct these observations.  My original reduce statement is redundant and is better written this way:  &gt;&gt;&gt; reduce(list.__add__, (list(mi) for mi in list_of_menuitems))   This is the correct syntax for a nested list comprehension (Brilliant summary !):  &gt;&gt;&gt; [image for mi in list_of_menuitems for image in mi]   But neither of these methods are as efficient as using itertools.chain:  &gt;&gt;&gt; from itertools import chain &gt;&gt;&gt; list(chain(*list_of_menuitems))   And as @cdleary notes, it's probably better style to avoid * operator magic by using chain.from_iterable like so:  &gt;&gt;&gt; chain = itertools.chain.from_iterable([[1,2],[3],[5,89],[],[6]]) &gt;&gt;&gt; print(list(chain)) &gt;&gt;&gt; [1, 2, 3, 5, 89, 6] Can you ready an action for "immediately before my next turn"? Does $x^{y^z}$ equal $x^{(y^z)}$? If so, why?   Why not simply apply the order of the operation from left to right? Meaning $x^{y^z}$ equals $(x^y)^z$?  I always get confused with this and I don't understand the underlying rule. Any help would be appreciated! I can always find that in some articles the production of higgs decay written as &quot;$\rm H\to {ZZ}^*\to 4l$&quot;, &quot;$\rm H\to ZZ\to 4l$&quot;, &quot;$\rm H\to Z\gamma^*\to\ldots$” What dose it mean when some particles with a superscript *? Such as “$\rm Z^*, W^*, \gamma^*, \ldots$&quot;. What’s the difference between them and &quot;$\rm Z, W, \gamma$&quot;? How to put terms in lexicographic order? The comment pop-up is too far away When you click the add a comment button when you don't have enough rep, you get a pop-up saying that you need more rep in able to comment. Except, it is too far away and users might be confused for a while before realizing the pop-up is on the other side of the page:     Clearly, that is very inconvenient for a lot of people, like me. Can we move the pop-up to be right next to the add a comment button? I am just curious, I use handlebar mounted lights, and since I have multiple bikes to switch, it's a lot of trouble changing the light from one to another. So, I am thinking of switching to helmet mounted lights.  Give me your point of view. Why or why not? Which is better suitable for which riding type? Debugging with command-line parameters in Visual Studio I'm developing a C++ command-line application in Visual Studio and need to debug it with command-line arguments. At the moment I just run the generated EXE file with the arguments I need (like this program.exe -file.txt) , but this way I can't debug. Is there somewhere I can specify the arguments for debugging? $\frac{1}{99989999} = 1.00010002000300050008001300210034005500890144... \times 10^{-8}$    (), which includes the Fibonacci sequence $(1\ 1\ 2\ 3\ 5\ 8\ 13\ 21\ 55\ 89\ 144\ldots )$.  This is fascinating to me but I can't figure out how this works, and a Google search doesn't seem to reveal anything. Add leading zeroes to number in Java? Blender build for Raspberry Pi3? QGIS Graphics Glitch after changing CRS Indian passport threading coming off My Indian passport threading is coming off i.e. the cover of the passport is coming off, there are only 2 threads remaining.   Will it be a problem at the airport when going abroad ? Also anyone who has experience of getting a replacement passport fairly quick ? Because I need to get a passport in like 15 days. Cross tabulation of two categorical variables: recommended techniques