 This should work:

     cat &quot;$API&quot; &gt;&gt; &quot;$CONFIG&quot;

You need to use the `&gt;&gt;` operator to append to a file.  Redirecting with `&gt;` causes the file to be overwritten. (truncated).

I have a set of HTML files and a SQLite database, which I would like to access from the browser, using the file:// scheme. Is it possible to access the database and create queries (and tables) using JavaScript?

Is it possible to access an SQLite database from JavaScript?

I have a column &#39;hour&#39;
I have a column &#39;kind&#39;  (it can be 1,2 or 3)

I&#39;d like to do something like: 

    SELECT count(id), SUM(hour) as totHour, SUM( IF ( kind = 1, 1, 0 ) ) as countKindOne

or

    SELECT count(id), SUM(hour) as totHour, COUNT( IF ( kind = 1 ) ) as countKindOne

But mysql tell me I&#39;ve an error... what&#39;s the error!?

Please see this stackoverflow topic: https://stackoverflow.com/questions/9083283/mysql-sum-if-field-b-field-a

.. I&#39;m not able to reply this ... 



MySql: is it possible to &#39;SUM IF&#39; or to &#39;COUNT IF&#39;?

&gt; **Possible Duplicate:**  
&gt; [Shell script to append text to each file?](https://stackoverflow.com/questions/5586293/shell-script-to-append-text-to-each-file)  
&gt; [How to append output to the end of text file in SHELL Script?](https://stackoverflow.com/questions/6207573/how-to-append-output-to-the-end-of-text-file-in-shell-script)  

&lt;!-- End of automatically inserted text --&gt;

I&#39;m trying to work out the best way to insert api details into a pre-existing config. I thought about using `sed` to insert the contents of the api text file to the bottom of the config.inc file. I&#39;ve started the script but it doesn&#39;t work and it wipes the file. 

    #!/bin/bash
    
    CONFIG=/home/user/config.inc
    API=/home/user/api.txt
    
    sed -e &quot;\$a $API&quot; &gt; $CONFIG
    
What am I doing wrong?


Append file contents to the bottom of existing file in Bash

> Possible Duplicate: 
> <a href="https://stackoverflow.com/questions/5586293/shell-script-to-append-text-to-each-file" target="_blank" rel="noopener noreferrer">Shell script to append text to each file?</a> 
> <a href="https://stackoverflow.com/questions/6207573/how-to-append-output-to-the-end-of-text-file-in-shell-script" target="_blank" rel="noopener noreferrer">How to append output to the end of text file in SHELL Script?</a>

I'm trying to work out the best way to insert api details into a pre-existing config. I thought about using <code>sed</code> to insert the contents of the api text file to the bottom of the config.inc file. I've started the script but it doesn't work and it wipes the file.
<pre><code class="hljs language-bash">#!/bin/bash

CONFIG=/home/user/config.inc
API=/home/user/api.txt

sed -e "\$a $API" > $CONFIG
</code></pre>
What am I doing wrong?

Does anyone know if we can say `set +x` in bash without it being printed:

    set -x
    command
    set +x

traces

    + command
    + set +x

but it should just print

    + command

Bash is Version 4.1.10(4). This is bugging me for some time now - output is cluttered with useless `set +x` lines, making the trace facility not as useful as it could be.


Bash set +x without it being printed

I have &quot;I love Suzi and Marry&quot; and I want to change &quot;Suzi&quot; to &quot;Sara&quot;.

    #!/bin/bash
    firstString=&quot;I love Suzi and Marry&quot;
    secondString=&quot;Sara&quot;
    # do something...

The result must be like this:

    firstString=&quot;I love Sara and Marry&quot;


Replace one substring for another string in shell script

Using:

    set -o nounset

1) Having an indexed array like:

       myArray=( &quot;red&quot; &quot;black&quot; &quot;blue&quot; )

    What is the shortest way to check if element 1 is set?&lt;br&gt;
I sometimes use the following:

       test &quot;${#myArray[@]}&quot; -gt &quot;1&quot; &amp;&amp; echo &quot;1 exists&quot; || echo &quot;1 doesn&#39;t exist&quot;

    I would like to know if there&#39;s a preferred one.

2) How to deal with non-consecutive indexes?

       myArray=()
       myArray[12]=&quot;red&quot;
       myArray[51]=&quot;black&quot;
       myArray[129]=&quot;blue&quot;

    How to quick check that `51` is already set for example?

3) How to deal with associative arrays?

       declare -A myArray
       myArray[&quot;key1&quot;]=&quot;red&quot;
       myArray[&quot;key2&quot;]=&quot;black&quot;
       myArray[&quot;key3&quot;]=&quot;blue&quot;

    How to quick check that `key2` is already used for example?

Easiest way to check for an index or a key in an array?

I am trying to output a string that contains everything between two words of a string:

input:

    &quot;Here is a String&quot;

output:

    &quot;is a&quot;

Using: 

    sed -n &#39;/Here/,/String/p&#39;

includes the endpoints, but I don&#39;t want to include them.



How to use sed/grep to extract text between two words?

What I&#39;m trying to do is find the current working directory and save it into a variable, so that I can run `export PATH=$PATH:currentdir+somethingelse`. I&#39;m not entirely sure if they have a variable that contains cwd by default.

How do I save the current directory in variable using Bash?

Save current directory in variable using Bash?

I would like to insert lines into a file in bash starting from a specific line.

Each line is a string which is an element of an array

    line[0]=&quot;foo&quot;
    line[1]=&quot;bar&quot;
    ...

and the specific line is &#39;fields&#39;

    file=&quot;$(cat $myfile)&quot;
    for p in $file; do
        if [ &quot;$p&quot; = &#39;fields&#39; ]
            then insertlines()     #&lt;- here
        fi
    done

Insert lines in a file starting from a specific line

I want to remove some *n* lines from the end of a file. Can this be done using sed?

For example, to remove lines from 2 to 4, I can use

    $ sed &#39;2,4d&#39; file

But I don&#39;t know the line numbers.  I can delete the last line using 

    $sed $d file

but I want to know the way to remove *n* lines from the end. Please let me know how to do that using sed or some other method.

How to use sed to remove the last n lines of a file

I have a file with many lines
in each line there are many columns(fields) separated by blank &quot; &quot;
the numbers of columns in each line are different
I want to remove the first two columns
how to?

how to remove the first two columns in a file using shell (awk, sed, whatever)

Straight to the point, I&#39;m wondering how to use grep/find/sed/awk to match a certain string (that ends with a number) and increment that number by 1. The closest I&#39;ve come is to concatenate a 1 to the end (which works well enough) because the main point is to simply change the value. Here&#39;s what I&#39;m currently doing:

    find . -type f | xargs sed -i &#39;s/$\?cache_version\=[0-9]\+$/\11/g&#39;

Since I couldn&#39;t figure out how to increment the number, I captured the whole thing and just appended a &quot;1&quot;. Before, I had something like this:

    find . -type f | xargs sed -i &#39;s/\?cache_version\=$[0-9]\+$/?cache_version=\11/g&#39;

So at least I understand how to capture what I need.

Instead of explaining what this is for, I&#39;ll just explain what I want it to do. It should find text in any file, recursively, based on the current directory (isn&#39;t important, it could be any directory, so I&#39;d configure that later), that matches &quot;?cache_version=&quot; with a number. It will then increment that number and replace it in the file.

Currently the stuff I have above works, it&#39;s just that I can&#39;t increment that found number at the end. It would be nicer to be able to increment instead of appending a &quot;1&quot; so that the future values wouldn&#39;t be &quot;11&quot;, &quot;111&quot;, &quot;1111&quot;, &quot;11111&quot;, and so on.

I&#39;ve gone through dozens of articles/explanations, and often enough, the suggestion is to use `awk`, but I cannot for the life of me mix them. The closest I came to using `awk`, which doesn&#39;t actually replace anything, is:

    grep -Pro &#39;(?&lt;=\?cache_version=)[0-9]+&#39; . | awk -F: &#39;{ print &quot;match is&quot;, $2+1 }&#39;

I&#39;m wondering if there&#39;s some way to pipe a `sed` at the end and pass the original file name so that `sed` can have the file name and incremented number (from the `awk`), or whatever it needs that `xargs` has.

Technically, this number has no importance; this replacement is mainly to make sure there is a new number there, 100% for sure different than the last. So as I was writing this question, I realized I might as well use the system time - seconds since epoch (the technique often used by AJAX to eliminate caching for subsequent &quot;identical&quot; requests). I ended up with this, and it seems perfect:

    CXREPLACETIME=`date +%s`; find . -type f | xargs sed -i &quot;s/$\?cache_version\=$[0-9]\+/\1$CXREPLACETIME/g&quot;

(I store the value first so all files get the same value, in case it spans multiple seconds for whatever reason)

But I would still love to know the original question, on incrementing a matched number. I&#39;m guessing an easy solution would be to make it a bash script, but still, I thought there would be an easier way than looping through every file recursively and checking its contents for a match then replacing, since it&#39;s simply incrementing a matched number...not much else logic. I just don&#39;t want to write to any other files or something like that - it should do it in place, like `sed` does with the &quot;i&quot; option.

How to find/replace and increment a matched number with sed/awk?

I have a file mixed with lower-case letters and upper-case letters, can I use `awk` to convert all the letters in that file into upper-case?

Can I use awk to convert all the lower-case letters into upper-case?

I am trying to get the first 22 characters from a unix data file.Here is my data looks as below.

First 12 characters is column 1 and next 10 characters is 2nd column.


    000000000001199998000180000     DUMMY RAG #         MFR NOT ST            1999980    ZZ-            0        0              0ZZ-
    000000000002199998000180000     DUMMY RAG #         MFR NOT ST            1999980    ZZ-            0        0              0ZZ-
    000000000003199998000180000     DUMMY RAG #         MFR NOT ST            1999980    ZZ-            0        0              0ZZ-
    000000000004199998000180000     DUMMY RAG #         MFR NOT ST            1999980    ZZ-            0        0              0ZZ-
    000000000005199998000180000     DUMMY RAG #         MFR NOT ST            1999980    ZZ-            0        0              0ZZ-
    000000000006199998000180000     DUMMY RAG #         MFR NOT ST            1999980    ZZ-            0        0              0ZZ-



How to get first n characters of each line in unix data file

I need to remove all the blank lines from an input file and write into an output file. Here is my data as below.



    11216,33,1032747,64310,1,0,0,1.878,0,0,0,1,1,1.087,5,1,1,18-JAN-13,000603221321
    
    11216,33,1033196,31300,1,0,0,1.5391,0,0,0,1,1,1.054,5,1,1,18-JAN-13,059762153003
    
    11216,33,1033246,31300,1,0,0,1.5391,0,0,0,1,1,1.054,5,1,1,18-JAN-13,000603211032
    
    11216,33,1033280,31118,1,0,0,1.5513,0,0,0,1,1,1.115,5,1,1,18-JAN-13,055111034001
    
    11216,33,1033287,31118,1,0,0,1.5513,0,0,0,1,1,1.115,5,1,1,18-JAN-13,000378689701
    
    11216,33,1033358,31118,1,0,0,1.5513,0,0,0,1,1,1.115,5,1,1,18-JAN-13,000093737301
    
    11216,33,1035476,37340,1,0,0,1.7046,0,0,0,1,1,1.123,5,1,1,18-JAN-13,045802041926
    
    11216,33,1035476,37340,1,0,0,1.7046,0,0,0,1,1,1.123,5,1,1,18-JAN-13,045802041954
    
    11216,33,1035476,37340,1,0,0,1.7046,0,0,0,1,1,1.123,5,1,1,18-JAN-13,045802049326
    
    11216,33,1035476,37340,1,0,0,1.7046,0,0,0,1,1,1.123,5,1,1,18-JAN-13,045802049383
    
    11216,33,1036985,15151,1,0,0,1.4436,0,0,0,1,1,1.065,5,1,1,18-JAN-13,000093415580
    
    11216,33,1037003,15151,1,0,0,1.4436,0,0,0,1,1,1.065,5,1,1,18-JAN-13,000781202001
    
    11216,33,1037003,15151,1,0,0,1.4436,0,0,0,1,1,1.065,5,1,1,18-JAN-13,000781261305
    
    11216,33,1037003,15151,1,0,0,1.4436,0,0,0,1,1,1.065,5,1,1,18-JAN-13,000781603955
    
    11216,33,1037003,15151,1,0,0,1.4436,0,0,0,1,1,1.065,5,1,1,18-JAN-13,000781615746


How to remove blank lines from a Unix file

Is it possible to append a single character to the end of `array` or `string` in java. Example:    
    
    private static void /*methodName*/ () {            
        String character = &quot;a&quot;
        String otherString = &quot;helen&quot;;
        //this is where i need help, i would like to make the otherString become 
        // helena, is there a way to do this?               
    }

Append a single character to a string or char array in java?

I am pretty proficient with coding, but now and then I come across code that seems to do basically the same thing. My main question here is, why would you use `.append()` rather then `.after()` or vice verses? 

I have been looking and cannot seem to find a clear definition of the differences between the two and when to use them and when not to.

What are the benefits of one over the other and also why would i use one rather then the other?? Can someone please explain this to me?

	var txt = $(&#39;#&#39; + id + &#39; span:first&#39;).html();
	$(&#39;#&#39; + id + &#39; a.append&#39;).live(&#39;click&#39;, function (e) {
	    e.preventDefault();
	    $(&#39;#&#39; + id + &#39; .innerDiv&#39;).append(txt);
	});
	$(&#39;#&#39; + id + &#39; a.prepend&#39;).live(&#39;click&#39;, function (e) {
	    e.preventDefault();
	    $(&#39;#&#39; + id + &#39; .innerDiv&#39;).prepend(txt);
	});
	$(&#39;#&#39; + id + &#39; a.after&#39;).live(&#39;click&#39;, function (e) {
	    e.preventDefault();
	    $(&#39;#&#39; + id + &#39; .innerDiv&#39;).after(txt);
	});
	$(&#39;#&#39; + id + &#39; a.before&#39;).live(&#39;click&#39;, function (e) {
	    e.preventDefault();
	    $(&#39;#&#39; + id + &#39; .innerDiv&#39;).before(txt);
	});

.append(), prepend(), .after() and .before()

I&#39;m having issues appending data to a list which is already in a list format. I have a program which will export results objects during a simulation loop. The data itself is stored as a list of matrices. My idea is to store those lists in a list, and then save this list of lists as an R object for later analysis, however I&#39;m having some issues achieving this correctly. I&#39;ll show what I&#39;ve done with small abstract example just using values instead of the matrix data from my simulation:

Say I&#39;ve run the simulation loop for 3 times.
During the iterations, the results lists need to be collected into the one list of lists that I will save as an R object:

List to contain the other lists and be saved: 
`outlist1 &lt;- list()`

First iteration:
`resultsa &lt;- list(1,2,3,4,5)`

`outlist &lt;- append(outlist1,resultsa)`

Second Iteration:
`resultsb &lt;- list(6,7,8,9,10)`

`outlist &lt;- append(outlist1,b)`

Third Iteration:
`resultsc &lt;- list(11,12,13,14,15)`

`outlist &lt;- list(outlist2,c)`


However, this solution does not work with growing a list containing lists this way, the desired result is:

    &gt;outlist
    [[1]]
    [[1]][[1]]
    [1] 1
    
    [[1]][[2]]
    [1] 2
    
    [[1]][[3]]
    [1] 3
    
    [[1]][[4]]
    [1] 4
    
    [[1]][[5]]
    [1] 5
    
    
    [[2]]
    [[2]][[1]]
    [1] 6
    
    [[2]][[2]]
    [1] 7
    
    [[2]][[3]]
    [1] 8
    
    [[2]][[4]]
    [1] 9
    
    [[2]][[5]]
    [1] 10
    
    
    [[3]]
    [[3]][[1]]
    [1] 11
    
    [[3]][[2]]
    [1] 12
    
    [[3]][[3]]
    [1] 13
    
    [[3]][[4]]
    [1] 14
    
    [[3]][[5]]
    [1] 15

However, instead what I get is:

    &gt; outlist3
    [[1]]
    [[1]][[1]]
    [[1]][[1]][[1]]
    [1] 1
    
    [[1]][[1]][[2]]
    [1] 2
    
    [[1]][[1]][[3]]
    [1] 3
    
    [[1]][[1]][[4]]
    [1] 4
    
    [[1]][[1]][[5]]
    [1] 5
    
    
    [[1]][[2]]
    [[1]][[2]][[1]]
    [1] 6
    
    [[1]][[2]][[2]]
    [1] 7
    
    [[1]][[2]][[3]]
    [1] 8
    
    [[1]][[2]][[4]]
    [1] 9
    
    [[1]][[2]][[5]]
    [1] 10

How do I grow a list, such that the resulting list formatted is like the desired result? If I do further analysis on these list I need to be able to easily access the elements.



Appending a list to a list of lists in R

In [this answer][1], it says (implies) that String concatenation is optimised into StringBuilder operations anyway, so when I write my code, is there any reason to write StringBuilder code in the source? Note that my use case is different from the OP&#39;s question, as I am concatenating/appending hundreds-thousands of lines.

To make myself clearer: I am well-aware about the differences of each, it&#39;s just that I don&#39;t know if it&#39;s worth actually writing StringBuilder code because it&#39;s less readable and when its supposedly slower cousin, the String class, is converted automagically in the compilation process anyway.


  [1]:  https://stackoverflow.com/a/1532499/1154376

Java: String concat vs StringBuilder - optimised, so what should I do?

I have a single list of numeric vector and I want to combine them into one vector. But I am unable to do that. This list can have one element common across the list element. Final vector should not add them twice. Here is an example:

    &gt;lst
    `1`
    [1] 1 2
    `2`
    [2] 2 4 5
    `3`
    [3] 5 9 1

I want final result as this

    &gt;result
    [1] 1 2 4 5 9 1

I tried doing following things, without worrying about the repition:

    &gt;vec&lt;-vector()
    &gt;sapply(lst, append,vec)

and

    &gt;vec&lt;-vector()
    &gt;sapply(lst, c, vec)

None of them worked. Can someone help me on this?

Thanks.

Content Type	Original Author	Original Content on Stackoverflow
Question	Grimlockz	View Question on Stackoverflow
Solution 1 - Bash	William Pursell	View Answer on Stackoverflow

Append file contents to the bottom of existing file in Bash

Bash Problem Overview

Bash Solutions

Solution 1 - Bash

MySql: is it possible to 'SUM IF' or to 'COUNT IF'?

Is it possible to access an SQLite database from JavaScript?

Attributions