When answering questions, I often find that I want to double-check that my answer is in-line with the most current version of the rules. Though I can often recognise that I need to check the errata when drawing on a book that I'm very familiar with, when an answer calls for drawing from many sources I usually won't have all that knowledge at my fingertips. What is the easiest way to know that a book has errata and where to find it?
I'm new to d20. I recently acquired a bunch of D&amp;D books and I'm sure they are all either 3.0 or 3.5, but it doesn't say in the book which version it is. How can I tell which version the book is?  For instance, I have "Complete Warrior - A Player's Guide to Combat for All Classes". It's hard back, published in '03. Is it 3.0 or 3.5?  Another example, I have "Sword and Fist - A Guidebook to Fighters and Monks". Perfect Bound, published in '01. Is it 3.0 or 3.5?
Valid characters in a Java class name What characters are valid in a Java class name? What other rules govern Java class names (for instance, Java class names cannot begin with a number)? Icons of Meta.SE and Stack Apps have gone missing It is possible to make ls -l output the size field with digits grouped by thousands? If so, how?  For instance:  $ ls -l -rw-rw---- 1 dahl dahl 43,210,052 2012-01-01 21:52 test.py   (Note the commas in the size).  Maybe by modifying the LC_NUMERIC setting inside the locale I'm using (en_US.utf8)?  I'm on Kubuntu 12.04 LTS. How can I explain to a non-native why the plural of a noun isn't used adjectivally? How can I explain to a non-native speaker that while this is correct:     The felling of trees.    And this is also correct:     tree felling   This is not:     *trees felling   To a non-native it seems very reasonable that since many trees are being felled and given that the felling of trees uses the plural, the inverse form would also use the plural and become trees felling.  To a native speaker such as myself, the latter is very obviously wrong, but I couldn't figure out how to formalize this into a rule that a non-native can understand. How to tell Google that I have changed my website URLs? Algorithm to return all combinations of k elements from n Local Coordinate to Geocentric The ultimate question, I need a transformation matrix to take a point in local space representing a roughly 500m x 500m place in New Mexico centered at -108.619987456 long 36.234600064 lat.  The final output needs to be in geocentric coordinates and I can during initialization get any number of points on the map such as the corners, center, western most along the center etc.  During run time I would like to have a transformation matrix that can be applied to a position in local space expressed in meters and get back an approximate GCC coordinate.  The center of the point in GCC: -1645380 -4885138 3752889 The bottom left corner of the map in GCC: -1644552, -4881054, 3749220  During run time I need to be able to multiply (-250, -250, 0) with the transformation matrix and get something close to (-1644552, -4881054, 3749220).  I've spent more than a week trying to research a solution for this and so far nothing.  Given an identity matrix as our starting position and orientation. Then using geotrans and the known lat, long, and height of the starting position I get an x,y,z geocentric coordinate. A vector from the origin of (0,0,0) gives both the up and translation for the matrix. However, I need the forward and right so that I can pass a distance in meters from the origin into the transformation matrix and get a roughly accurate GCC. Do I have all of the inputs I need to calculate the right and forward?  Inputs Origin: 0, 0, 0 Global: -1645380, -4885138, 3752889 Up (Normalized): Global - Origin  Desired Outputs Right: ? ? ? Forward: ? ? ?  So with the right and forward added to the up and translation I already calculated I would have a transformation matrix.  I could then apply the matrix to a vector of say (50, 50, 0) and get something within about 0-3 cm of the output if I feed the lat/long back into geotrans.  This matrix would only ever be used small maps of about 500m x 500m so the curvature of the earth is negligible.  In reply to whuber,  I don't know your level of experience so I will start with the very basics.  An identity matrix is a 4x4 matrix that you can multiply by a vector and it returns the vector unchanged. Such as below.  1 0 0 x=0 0 1 0 y=0 0 0 1 z=0 0 0 0 1  The x, y, and z of the matrix are how much to translate the vector by and the first 3 rows and columns are the rotation.  Below is a tranformation matrix that does nothing to the orientation of a vector but does translate.  This is what you would want for two axis aligned worlds in different locations.  1 0 0 13 0 1 0 50 0 0 1 -7 0 0 0 1  If you were to multiply a vector of (10, 10, 10) with the above transformation matrix you would get an output of (23, 60, 3).  My problem is the axes are not aligned and the "plane" of the world I am trying to get the local coordinate converted to is projected on the ellipsoid of the earth.  Geotrans is library that you can use to pass a coordinate from one system such as geodetic or GDC (lat, long, height) and get back another such as geocentric or GCC (x,y,z).  For example: If my game world was representing a map centered exactly on the prime meridian and equator the transformation matrix would look something like below. I am just guesstimating the Y and Z rotations and might have them flipped and/or the wrong sign.    0 0 1 6378137 0 1 0 0 1 0 0 0 0 0 0 1 Say I have a Zombie token, , and  on the battlefield. Can I sacrifice the Zombie token to activate both the Altar's and Seer's abilities?  Similarly, if I have one card in hand, and  and  on the battlefield can I discard the one card to both of their abilities?  If I have a  with 3 charge counters can I activate both of its abilities by tapping it to add a counter, and tapping it to remove 3 counters and destroy a permanent without untapping it in between? I have been having a discussion regarding the Shape Water cantrip from the Elemental Evil Player's Companion. A friend and I are trying to come to an accurate view of how this spell actually functions.   Some example questions:   Must the targeted water be within a 5 foot cube area, or does it need to be of a volume not exceeding 125 cubic feet? If you shape water that is within a 5 foot cube, can the final shape you animate it to extend outside the cube? Can you cause the shaping to affect ice and snow, or only liquid water? Would you be able to carry a globe of water alongside you over distances?   Really, there are two parts:    What can be targeted by the spell? What are the limitations on the 'shape and animate' portion of the spell?   The answer I am looking for, if possible, would use the language of the spell, possibly with precedent from other game text, to clearly define the limitations of this cantrip. Basis of the null space Find the basis of the null space for the matrix  $$D = \begin{bmatrix}0 &amp; 0 &amp; 0 &amp; 0\\0 &amp; 1 &amp; 1 &amp; 0\\1 &amp; 1 &amp; 0 &amp; 0\\1 &amp;1 &amp; 0 &amp; 0\end{bmatrix}.$$  I computed the solution by letting eigenvectors $(x,y,z,w)$ such that $y+z=0,x+y=0$, and I got a basis vector $\{(1,-1,1,0), (0,0,0,1)\}$ . But from one textbook  I have found the solution as $\{(1,0,0,0),(0,0,1,1)\}$. May I made a mistake? Thanks! What is the best way to vertically center the content of a div when the height of the content is variable.  In my particular case, the height of the container div is fixed, but it would be great if there were a solution that would work in cases where the container has a variable height as well. Also, I would love a solution with no, or very little use of CSS hacks and/or non-semantic markup. How to update Wine to the latest version? I am a Canadian citizen, and I intend to travel to the US for a student clinical elective at a university in Texas for the months of September and October. The university will help me obtain an F-1 status. However, I want to attend a few conferences and educational seminars which are being held in November/December for which I will be using a B1/B2 visa.  Will I have to leave the US and come back in November using a B1/B2 visa, or is there another way to change my visa status, or can I apply for both visas upon entering the US? What are good basic statistics to use for ordinal data? I have some  gained from survey questions.  In my case they are  responses (Strongly Disagree-Disagree-Neutral-Agree-Strongly Agree).  In my data they are coded as 1-5.  I  don't think means would mean much here, so what basic summary statistics are considered usefull? When is "to" a preposition and when the infinitive marker? Disable Hyperlink on a SharePoint 2013 page I want to disable the hyperlink for a specific class part of Site Feeds in SharePoint 2013.  I`m using Jquery to do the same, but it is not working for me. Code for reference  &lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.3/jquery.min.js"&gt;&lt;/script&gt; &lt;script type="text/javascript"&gt;     var location= $('.ms-microfeed-userName ms-textLarge ms-subtleLink').attr("href");  $(".ms-microfeed-userName ms-textLarge ms-subtleLink").removeAttr('href');  $('ul').addClass('expanded');  $('ul.expanded').fadeIn(300);  $(".ms-microfeed-userName ms-textLarge ms-subtleLink").attr("href", location);    &lt;/script&gt; What do you call the functions that make a composite function.  Example : $e^{\sin x} $ is made up of $\sin x$ in the argument of $e^x$  So what are $\sin x$ and $e^x$ called here in this context? Basic functions or something?   (Please don't tell me the former is trig and latter is exponential function, I know that, but that's not what I'm asking here, please try to understand)  Hope I made myself clear. 2 different bibliographies I'm writing my thesis and I would like to make 2 "bibliography" references: The first one would be for the publications I'm in and the second one for external references. I've made one *.bib file right now and it's working but I have no idea how I should work with 2 *.bib files.  Any suggestion will be appreciated. How to check if a column exists in a SQL Server table? Force ssh to not print "Remote host identification has changed" warning Is there a way to avoid ssh printing warning messages like this?   @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@   Although the remote host identity has changed but I know it is fine and  just want to get rid of this warning.