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I'm trying to run  sed -i "/$variable/c \$variable1' file.txt   But it's not displaying any change in the file: file.txt.  But the same command, with out the variables works fine:  sed -i "/variable/c \variable1' file.txt Adding "noise" to overlapping X,Y coordinates so no longer in EXACT same place? I have a series of points representing animal observations. Many of them overlap, having the exact same coordinates, and this is causing me trouble when I want to run some analytical tools which requite no identical points. I was wondering if there's any tool that can add some "noise" to the coordinates, that's to say, adding some random decimal values at the end in order to obtain slightly different coordinates which are still close enough in space so as to not really modify the observation. I've heard about such a tool, but I can't find it, at least in ArcGis 10. Maybe there's another software that can do it? Thanks! I'm looking to create a simple short-lived reservation system, and I'd like to generate confirmation numbers that are   unique random-looking alphanumeric short-ish, at least much shorter than 32 character-long strings returned by sha1   I'm only looking to have ~500 reservations, so I don't imagine high likelyhood of collissions.  One idea I had is generate an sha1 hash based on a date-time stamp and username, then truncating it to its first 10 characters.  Would something like that be reliably unique enough for the purposes of processing ~500 reservations? Training involved to ride 175 miles (281 km) in a day I want to be able to ride 175 miles (281 km) in a day (to do the ). I used to be able to do about 60 miles (96.5 km), only once hitting 80 miles (128 km), but I'm out of shape now. Wondering how I can systematically train to get to 175 miles at an average of 15 mph (24 km/h) Are there guides out there to help with this?  What's some advice?  [update] The  will happen each year, so my intention isn't to ride this year, rather what do I need to do to ride it in some future year? I have this recipe for cheese curds that I want to try: , but it specifically calls for raw milk which is near to impossible to get here. I make yogurt with pasteurized milk and it works no problem, but does cheese somehow work differently? I have a query where I chain two columns. Why does the alias not work in the GROUP BY clause but in ORDER BY clause, it does work? How can I write the select correctly?  SELECT   KOS_VER_ID        AS "Vertrag"   , WHR_ISO_3_CODE  AS "Waehrung"   , KOS_KOA_ST_KZN || '  -  ' || ST_LANGBEZ_EN as "Kostenart"   , SUM (KOS_BETRAG) AS "Summe pro KOA" FROM   KOSTEN   , WAEHRUNG   , SCHLUESSELTABELLE WHERE    KOSTEN.KOS_VERHI_WHR_ID = WAEHRUNG.WHR_ISO_ID   AND KOSTEN.KOS_KOA_ST_KZN = SCHLUESSELTABELLE.ST_ID   AND KOS_VER_ID in (2509, 2510, 2511) GROUP BY   KOS_VER_ID   , WHR_ISO_3_CODE   , KOS_KOA_ST_KZN || '  -  ' || ST_LANGBEZ_EN ORDER BY   "Vertrag"   , "Kostenart" ; Let $A$ be a complex matrix such that $A^n = I$, show that $A$ is diagonalisable.  How do I do this?    I would hazard a guess that since $A^n = I$ that means that $A^n$ is obvious diagonal, and I suppose that a diagonal matrix can only be formed by the square of another diagonal matrix, but I am not sure if that is the case. Also I think this neglects the complex cases.  Is there a Jordan block argument that I should use? Need to prove that $(S,\cdot)$ defined by the binary operation $a\cdot b = a+b+ab$ is an abelian group on $S = \Bbb R \setminus \{-1\}$. So basically this proof centers around proving that (S,*) is a group, as it's quite easy to see that it's abelian as both addition and multiplication are commutative. My issue is finding an identity element, other than 0. Because if 0 is the identity element, then this group won't have inverses.  The set explicitly excludes -1, which I found to be its identity element, which makes going about proving that this is a group mighty difficult. How to include SVG diagrams in LaTeX? I'm making all my diagrams in SVG format using Inkscape and then I export them to some other format (e.g. PDF, EPS or PNG). I wrote a short script that does this for me automatically, but I'd like to avoid this step, if possible --- sometimes the conversion from SVG converts the text labels into vectors, and that's annoying. Hence the question:  Is there a way to include SVG diagrams directly without conversion to an intermediate format?  Package suggestions, or instructions for specific LaTeX distribution are welcome. Tips and personal experience on which tools you have found to be working reliably would be also appreciated. I sometimes browse erotic media files but I would like to avoid having them appear in files &amp; folders / recent. How can I do that?  The old "making .recently-used.xbel a folder" trick from 10.10 and older doesn't work any more.   Plus I'd prefer to turn off tracking only temporarily.  I also prefer not to use a separate user for this, as switching users sometimes isn't fast enough. Filling a conical tank I have been working on this problem for about 2 hours and I can't seem to get it, here is exactly what the question reads. "Water is poured into the top of a conical tank at the constant rate of 1 cubic inch per second and flows out of an opening at the3 bottom at a rate of .5 cubic inches per second. The tank has a height of 4 inches, and a radius of 2 inches at the top. How fast is the water level changing when the water is 2 inches high?" Is there a word to describe someone who tends to disagree with others only to upset them? What's the word to describe someone who acts arrogantly and always disagrees with others unreasonably in order to upset people around him/her?  [I'm not looking for adjectives like unpleasant, annoying, unfriendly, rude, I'm looking for a more specific term like opinionated, didactic, loquacious, gregarious ]  I think I'd come across it before but I've forgotten what it is.. Does Google treat different ports as different sites? I'm trying to recall the name of a book I read, probably published after 1990, where alien AI infects satellites and a barrier is established, isolating earth from space that maybe slows down time inside of it, relative to the passage of time outside.  Mars or the moon is also colonized in an attempt to flee the now real possibility that the sun will become a red giant and wipe out humanity in the not-too-distant future (as perceived on earth), but the colony gets one of the time barriers as well.  I think the name of the novel was short, "The _______" (one word).  The story focused more on the human cost and followed one particular family, one member of which was somehow also partially infected by the alien AI, but I don't remember as much about them. Prove that $L(V,W)$ forms a vector space Let $V$ and $W$ be vector spaces over a field $F$. Let $L(V,W) = \{T:V\to W : T \text{ is linear} \}$, that is, $L(V,W)$ is the collection of all linear functions from $V$ to $W$. For $S,T \in L(V,W)$ and $a \in F$, define new functions $(S+T):V \to W$ and $ aT :V \to W$ by $(S+T)(x) = S(x)+T(x)$ ; $(aT)(x) = a(T(x))$.   Prove that $S+T$ belongs to $L(V,W)$ and $aT$ belongs to $L(V,W)$. Master database is corrupt, instance won't start - what are my options? Help! My master database is corrupt, I can't even bring the SQL instance online! What are my options to get my server back up?   I do have a backup of master, but the  asks me to start the instance in single-user mode, which I can't do!  (Note: I'm leaving this question unspecified as to SQL version, so as to be a more widely-applicable reference. There are some similar questions on DBA.SE, but none that involve the server unable to start.) How do I match any character across multiple lines in a regular expression? For example, this regex  (.*)&lt;FooBar&gt;   will match:  abcde&lt;FooBar&gt;   But how do I get it to match across multiple lines?  abcde fghij&lt;FooBar&gt; warning message at command line `sudo` Everytime I try to sudo something at the terminal, I get a warning message:  alexandre@XPS-15Z $ sudo mount file.iso /mnt/ -o loop [sudo] password for alexandre:  no talloc stackframe at ../source3/param/loadparm.c:4864, leaking memory   It's just annoying to get that all the time. How do I solve that? I'm on Ubuntu 14.04 (upgraded from 13.10) My last name is not the same on ticket as on passport; rest of details are same I'm traveling from JED Saudi Arabia to Singapore by Saudi airlines. My last name doesn't match the passport. But all other details are same, e.g. passport no., DOB, etc. What's the difference between:        Have someone do something     Make someone do something   Get someone do something.      To have someone do something means to cause someone to do something. To make someone do something means to force someone to do something. To get someone do something means to persuade someone or trick someone to do something.  This is what the dictionary says but I saw they're sometimes interchangeably used, so dictionary definitions are not enough.