When I use the aggregation framework to get values from my database and I got complex data structures, such as arrays of struct with doubles, I get inaccurate values.   I use the ToList() on my IAsyncCursor to get my values. The double values should be such as 13.23 and in the return json string the values are like 13.2300000001 or something like that. This is just a behavior if I use this complex structures of data.  What can I do against this Inaccuracy? Am I using the false classes and methods of the csharp api?
Consider the following code:   0.1 + 0.2 == 0.3  -&gt;  false   0.1 + 0.2         -&gt;  0.30000000000000004   Why do these inaccuracies happen?
ffmpeg working from command line in Terminal but not in an Automator shell script! I have just compiled my own copy of ffmpeg on my system and it's located in the following path:  /opt/local/bin/ffmpeg   When I run the following command in Terminal.app, it runs smooth:  ffmpeg -i /Users/Amit/Documents/input.avi -c:v copy -c:a aac -b:a 384k -strict -2 /Users/Amit/Documents/output.m4v   However, a similar command run as a shell-script in an Automator service fails:  for f in "$@" do     ffmpeg -i "$f" -c:v copy -c:a aac -b:a 384k -strict -2 "${f%.*}.m4v" done   Up until now, I had a pre-compiled build of ffmpeg on my system located at:  /Applications/Scriptlets/   And my Automator shell-script had the full path (/Applications/Scriptlets/ffmpeg) instead of just ffmpeg; and it worked fine. However, today I decided to compile a fresh copy of ffmpeg using MacPorts and removed the earlier version from my Applications/Scriptlets folder. Now, this ffmpeg works fine in Terminal but gives an error whenever I try running it from a shell-script inside of an Automator workflow. Am I doing something wrong here? Please help! Looking for a simple proof that groups of order $2p$ are up to isomorphism $\mathbb{Z}_{2p}$ and $D_{p}$ . I'm looking for a simple proof that up to isomorphism every group of order 2p (p prime) is either $\mathbb{Z}_{2p}$ or $D_{p}$ (The Dihedral group of order 2p).  I should note that by simple I mean short and elegant and not necessarily elementary. So feel free to use tools like Sylow Theorems, Cauchy Theorem and similar stuff.  Thanks a lot! At most finitely many (Hamel) coordinate functionals are continuous - different proof Why would you not want to rollover a previous employer's 401(k) when changing jobs? Are there any valid reasons to not rollover a former 401(k) when changing jobs?  I have several little ones that I never quite got around to rolling together - with an upcoming job change, should they all be combined into my new employer's retirement plan?  If not, what else might be considered? Determinant of a non-square matrix I wrote an answer to  question based on determinants, but subsequently deleted it because the OP is interested in non-square matrices, which effectively blocks the use of determinants and thereby undermined the entire answer. However, it can be salvaged if there exists a function $\det$ defined on all real-valued matrices (not just the square ones) having the following properties.   $\det$ is real-valued $\det$ has its usual value for square matrices $\det(AB)$ always equals $\det(A)\det(B)$ whenever the product $AB$ is defined. $\det(A) \neq 0$ iff $\det(A^\top) \neq 0$   Does such a function exist? Why don't players get extra xp for large encounters? Based on the table Encounter XP Multipliers from the Basic Rules' DM section, Page 57, when you're building encounters in 5E, you include an XP modifier depending on the number of creatures your PCs will be fighting: 1.5x for a pair, 2x for 3-6 and so on. However, the PCs only get the base XP as a reward.     This doesn't change the actual xp reward ... just your calculations of how difficult the encounter is.   Why is this? After acknowledging that battles vs multiple opponents are more difficult, why not reward them as such? Basically, I want to have a single operator which can do multiple things, based on some attributes values.  class MyPanel(bpy.types.Panel):     # (...)     layout = self.layout     row = layout.row()     row.operator("my.button", text="Button text")  class MY_BUTTON_OT_Button(bpy.types.Operator):     bl_idname = "my.button"     bl_description = "Button description"     bl_label = "Button"     foo = bpy.props.IntProperty()     bar = bpy.props.BoolProperty()      if bar:         # Do something with foo     else:         # Do something else :P   I know how to set one attribute, like so:      row.operator("my.button", text="Button text").foo=5   But what about multiple arguments? I tried several things that didn't worked, like (e.g.):   With setattr(): row.operator("my.button", text="Button text").setattr(foo=5,bar=True)   With a custom method setVal() in the operator class: row.operator("my.button", text="Button text").setVal(foo=5,bar=True)   Maybe I must use a single EnumProperty? I hope to avoid this, so my question is: Is it possible to pass multiple custom arguments to set attributes in an operator class? And if yes, how ?  Thanks for your help. Are there guidelines on how much free RAM a phone should have - specifically Samsung Galaxy S? I have a Samsung Galaxy S (AT&amp;T Captivate) that is rooted.  I have various ways to tweak the amount of free RAM the OS leaves on the phone.  The default is 48 MB, but I was wondering if I could actually go lower without impacting phone performance.  Are there guidelines posted anywhere, or that can be deduced based on knowledge of the Android platform?  Or should I trust that the default settings are appropriate?  I understand that when it comes to free RAM, more isn't necessarily better, but I understand that there is still a threshold that I don't want to dip below.   I'm running a 2.3.6 Gingerbread based ROM.  For what it's worth, I'm running the Zeam launcher. After I factory reset my Nokia 6, this icon appeared. I've never seen it before. What is this icon in the highlighted part? How are embedded quotations used? How would embedded quotations be used when quoting from passages/sources within an essay? What would be the difference between normal quotations and embedded quotations? Recently I installed Ubuntu 12.10 x64 Server Edition on my PC. Unfortunately, I attempted to install a lightweight desktop but due to the fact that I have an old graphics card, the PC does not perform so well. I am thinking of re-installing an Ubuntu version but I do not want to lose the contents in my home folder. Is there any way to do that with a Live CD? Should individual letters be preceded with "an"? I was reading a comic book and I noticed that the author used "an A" and "an N" in a particular phrase (screenshot below). While I understand the usage of "An A" here (A being a vowel and what not) and "N" having a pronunciation which has a sound similar to "A".  Since most of English alphabets have pronunciations which start with a syllable similar to one of the vowels or semi-vowels; is it OK to prefix the letters using "An"?  For eg. An X, or An Y.        Zenescope's Grimm Fairy Tales - Werewolves: The Hunger, page #8 (Click to enlarge) How can momentum but not energy be conserved in an inelastic collision? Page number position I am working on a long document in LaTeX with documentclass book. I need the page number to always be in the upper right corner of each page, even if that page is the first page of a chapter (right now on 1st pages of chapters, the page number is bottom-centered, on all other pages it's top-right).  I control the position of the page number with fancyhdr:  \usepackage{fancyhdr} \pagestyle{fancy} \lhead{} \chead{} \rhead{\thepage} \lfoot{} \cfoot{} \rfoot{} \renewcommand{\headrulewidth}{0pt}   Also, I don't know if the problem is related but my chapters do not start from the top of the page. There is a white area, then comes chapter X, then a newline with the chapter line. What I also want is the chapter to start from the top of the page.  The main question here is how I can get the page number to always appear in the upper right corner, I mention the thing with the chapter title position only in case that might be related. Italics/roman in BibTeX I use a BibTeX style which automatically italicises booktitles (using \emph). I have certain entries which contain italicised words in the title. I would like these to appear non-italicised (in roman) in the final PDF output. Using any of \emph or \textit or \textrm on these items doesn't seem to make any difference -- the whole title still appears in italics.  Minimal .bib entry  @PHDTHESIS{klein1974, author = {Klein, Jared S.}, title = {The Particle \emph{u} in the {R}igveda}, school = {Yale}, year = {1974}, address = {New Haven, CT}, timestamp = {2009.12.04} }   Minimal .bbl entry generated by sp.bst:  \bibitem[{Klein(1974)}]{klein1974} Klein, Jared~S. 1974. \newblock \emph{The particle \emph{u} in the {R}igveda}. \newblock New Haven, CT: Yale dissertation. I would like to simulate the behaviour of a zener diode in LTspice. Consider the following schematic         &ndash; Schematic created using   I'm interested in simulating its performance when Vcc changes from the rated value (say 12V), for example when Vcc varies from 11 to 15 V.  Now, I know how to simulate this behaviour in LTspice for a generic diode or even for a particular diode which is available in the model library, but when it comes to using a custom diode, I have no idea on how to specify the diode parameters.  Looking into the documentation I was able to come up with a setup that is the correct one, that is, I can specify a custom diode model but now I'm having problems in understanding where to find all the parameters since the datasheet of my diode of choice does not provide all of them. In the LTspice model shown below I've picked a 4.7 V zener diode that was available just to have a base model to edit (and a 1k resistor just for reference).    The diode I'd like to use is a 3V . How can I simulate, as realistically as possible, the behaviour of this diode given the few parameters available in the datasheet? Finding the unique rock with its weight I have 12 rocks, all have the same weight except for one rock, but I don‘t know which rock is. How do I know which rock is different from other, and also know that rock heavier or lighter, with maximum 3 comparating steps. My only tool is just a balance that can only compare the weight between the rocks. What are the best books to study Neural Networks from a purely mathematical perspective? I am looking for a book that goes through the mathematical aspects of neural networks, from simple forward passage of multilayer perceptron in matrix form or differentiation of activation functions, to back propagation in CNN or RNN (to mention some of the topics).  Do you know any book that goes in depth into this theory? I've had a look at a couple (such as Pattern Recognition and Machine Learning by Bishop or Deep Learning by Goodfellow, Bengio and Courville) but still have not found a rigorous one (with exercises would be a plus). Do you have any suggestions? Although we can create or update fieldsets using salesforce UI but Is there any way to insert or update FieldSets using apex code (using metadata or API calls) ? 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.