When dissolving a polygon shapefile I get fragments in the middle (see pictures) in Qgis and R using the functions from rgeos. Has anybody an idea where this comes from and what can be done to deal with this?   original data set showing municipalities   dissolved dataset showing fragments in the middle    I would like to have only the contour of all municipalities without the fragments...
I have a set of polygons representing administrative districts.  The districts were digitized by hand, and there are small spaces (slivers) between polygons where the polygons should be touching. How can I have the polygons snap together, removing the spaces?
python multiprocessing on windows, if __name__ == "__main__" I have been experiencing an issue that once I have a material created and looking the way I want it, I cannot seem to export it correctly with the textures mixed.  I don't know the correct words to use, but in blender I have the material created using the nodes editor, and I have placed two textures inside of there (one for the rock texture and one for moss, my object is a rock). When I export this model and import to Unity (the game engine I am using), I find a materials folder but the material inside of it does not have the textures assigned, it's just a plain white material?  How can I export my material from blender in a way that it will allow me to import it WITH TEXTURES into Unity? WP_query 'orderby=none' Problem I have another database which stores post's IDs and I want do display them using WP_query to use the WP default pagination. I'm using orderby => none to preserve the original order, but the result reorders them by IDs.  $ids = array (60, 23, 78, 46, 105, 130)  $args = array (     'posts_per_page' =&gt; -1,     'post__in' =&gt; $ids,     'orderby' =&gt; 'none' );  $query = new WP_Query ( $args );  while ( have_posts() ) : the_post();     echo '&lt;li&gt;';     the_title();     echo '&lt;/li&gt;'; endwhile;   Could anyone help me?  Thanks, Romulo De Lazzari How to override parent functions in child themes? I've been reading around and trying to figure out how to do this, but for some reason I can't seem to override parent functions in my child theme.  I'm using TwentyTen as a parent - can anyone tell me why this function in my child theme isn't overriding the parent function please?  // Override read more link function osu_twentyten_continue_reading_link() {  return ' &lt;a href="'. get_permalink() . '"&gt;' . __( 'Read on &lt;span class="meta-nav"&gt;&amp;rarr;&lt;/span&gt;', 'twentyten-child' ) . '&lt;/a&gt;'; } function osu_twentyten_auto_excerpt_more( $more ) {  return ' &amp;hellip;' . osu_twentyten_continue_reading_link(); } remove_filter( 'excerpt_more', 'twentyten_auto_excerpt_more' ); add_filter( 'excerpt_more', 'osu_twentyten_auto_excerpt_more' );   I thought you had to remove the filter/action etc. before re-adding it right?  Thanks,  osu Is $K[a,b]=K(a,b)$ for algebraic $a, b$? What is the importance of eigenvalues/eigenvectors? Getting an "Authentication token manipulation" error when trying to change my user password I am logging in to my Ubuntu Server using my username. Once I am logged in I am typing passwd command. Entering a new password but a second after getting following error messages:  passwd: Authentication token manipulation error passwd: password unchanged   What is wrong here? How can I change my password otherwise if I don't have access to that server physically, i.e. I am connecting remotely with ssh using terminal. On the canonical isomorphism between $V$ and $V^{**}$ Do not load Facebook-based avatars directly from the Facebook CDN Users who register for their account via Facebook get  as their default avatar. However, the avatar is not copied to SE servers or Imgur, and thus the original URL is kept. This URL compromises the privacy of the user as it contains their Facebook user ID which everyone can easily extract and then view the profile.  The image is also not visible at all to those who have Facebook blocked for their own privacy (by extensions such as Ghostery or browser features ), or due to network policy (e.g. some work and school networks block Facebook).  With the new avatar system, it would be much better if the Facebook photo was stored like a manually uploaded avatar to avoid this problem. Is the cube root of a prime number rational? The question is: if $P$ is prime, is $P^{1/3}$ rational?   I have been able to prove that if $P$ is prime then the square root of $P$ isn't rational (by contradiction) how would I go about the cube root? Repeatedly rolling a six sided die four times and summing the highest three results gives you a distribution with what mean and standard deviation? Repeatedly rolling a six sided die four times and summing the highest three results gives you a distribution with what mean and standard deviation?  I've only taken AP statistics, but I would like to learn how to do this. Which is grammatically correct?  I can only do so much in this time.  or  I can do only so much in this time. I would like to render an animation as a series of .png images with transparent backgrounds for use in a video. Is this possible? /usr/bin/sudo must be owned by uid 0 and have the setuid bit set I have run following command accidentally   sudo chown [username] -hR /   Now sudo su getting error:  sudo: /usr/bin/sudo must be owned by uid 0 and have the setuid bit set   How to Solve This? Comments/tips on a (non Latex) pdf including mathematical formulas My goal : I correct copies from students that I scan to pdf. I wish I could make the annotations on the scanned copies rather than on the physical paper. Today, I have to scan the copies again to have my annotations transferable to students by email. Since most of the annotations are similar, I wish to have a stock of annotations I could transfer on the copies.  I went through a lot of technologies, including many "StackExchange Questions" here. I considered pdfcomment, cooltips, fancytooltips, the OCG family (ocgx, ocgp, ocg2, ...), etc.  Two tracks attracted more specifically my attention :    pdfcomments : I like the mouseover to see the comment, the capabillity to move the annotation around so I can have a stock on a pdf and I can copy it onto the scanned copies. This would be my choice if there was not a main drawback : it accepts only plain text when I need to use mathematical notations. (It needs selected pdf readers). Because you can move comments, you can put them on any pdf, even if it is not compiled from Latex or if you don't have the source. fancytooltips : I like the mouseover to see the comment, and the capability to use LaTeX mathematical formulas and images. Drawbacks : I can't move the annotation from a pdf document to the copies. (It works with very few pdf readers.) . I am not sure whether I can put tips on non Latex pdfs.   Is there a way to have pdfcomment have images/Latex mathematical formulas (or references to formulas that can show with a mouseover) ? Or is there a way to transfer fancytooltips to a non Latex pdf ? Or are there other techniques to achieve the goal ? Maximum total distance between points on a sphere What is the configuration (set of locations) of $n$ points on the surface of a sphere such that the sum of distances is maximum for $n=1,2,3,...$?  The sum of distances is measured by summing the lengths of every straight line (through the sphere) connecting every possible combination of $2$ points.  All the points are on a single sphere of radius $R$.  Here's a visualization:   Acknowledgements: Based on  Physics S.E. question. Image from . How can I read my hard drive’s SMART status in Windows 7? How can I read the  S.M.A.R.T. state of my HDDs while using Windows 7, either automatically or manually? Proving that $\sum\limits_{k=0}^{n} {{m+k} \choose{m}} = { m+n+1 \choose m+1 }$ I have to prove that:     $$\sum_{k=0}^{n} {{m+k} \choose{m}} = { m+n+1 \choose m+1 }$$   I tried to open up the right side with Pascal's definition that: $$ { n \choose k} = {n-1 \choose {k}} + {n-1 \choose {k-1}}$$  Here is what I came up with, and I am sure it is wrong because it does not equal the left side:  $$ {m+n+1 \choose m+1} = {m+n \choose m+1} + {m+n \choose m} = ... ={m+n \choose m+1} + {m+n-1 \choose m} + {m+n-2 \choose m-1} + ... + {m \choose m+1} = \sum_{k=0}^{n} {m+k \choose m+k-n+1 }  $$  Which, again, probably is wrong because it is not equal $\sum_{k=0}^{n} { m+k \choose m}$. Any help is appreciated I can't figure how to print the string "-n" with the over 30 years-old command echo.  I tried these:  Michaels:Scripts$ echo -n Michaels:Scripts$ echo "-n" Michaels:Scripts$ echo -e "-n" Michaels:Scripts$ echo -- -n -- -n Michaels:Script$ echo -- "-n" -- -n Michaels:Script$ echo "\-n" \-n   I use Mac OS X ML. I consider this behaviour very weird and unexpected. How can I log into a different Google account? It only shows one of my Google accounts. I want to log into a different one but I don't want them connected in any way. What do I do?