I have a text file:
Function Description
concat Returns the concatenation of the arguments.
contains Returns true if the first argument string contains the second argument string; otherwise returns false.
I'd like to wrap the text on column#2, the result should be:
Function Description
concat Returns the concatenation
of the arguments.
contains Returns true if the first
argument string contains
the second argument
string; otherwise returns
false.
How to do it in vim or shell quickly? Thank you for any suggestions.
The issue can be easily solved in Vim by using the indentexpr option. Set
it to the number of characters designated for the first column,
:set inde=16
then format the text as usual with the gq or gw families of commands.
I don't think this qualifies as "quickly", and I hope someone out there has a better answer, but this is the best I could come up with in vim:
1) Set textwidth to the desired width of your second column:
:set tw=60
2) Mark the first-column words with something special (to be removed later - any non-normal text will do, I'm using jjj here) (using g!/^$/ to ignore empty lines):
:%g!/^$/s/^/jjj/
3) Put the second column text on a separate line:
:%s/ \</ \r/
4) Rewrap all the second-column lines to the desired width:
:%g!/^jjj/normal gqq
5) Join the first line of each second-column paragraph with its first-column word (should preserve the space that was after the first-column words at the beginning):
:%g/^jjj/join
6) Indent all the remaining second-column lines the appropriate amount to line them up (use however many >>s are needed - there may be a way to make vim check the length of the last first-column line and insert that number of spaces instead of using this method):
:%g!/^jjj/normal >>>>>>>>
7) Finally remove the first-column marker from the first columns:
:%s/^jjj//
Not worth it for your example, but if the file's large enough, it's better than doing it by hand...
:set tw=80 #or :set textwidth=80
Would wrap text to 80 chars.
Then you can type in command mode:
gg #go to the top
and then
gqG #apply reformat to the end
Reference:
http://www.cs.swarthmore.edu/help/vim/reformatting.html
Related
I'm working on a small text file with a list of words in it that I want to add a new word to, and then sort. The file doesn't have a newline at the end when I start, but does after the sort. Why? Can I avoid this behavior or is there a way to strip the newline back out?
Example:
words.txt looks like
apple
cookie
salmon
I then run printf "\norange" >> words.txt; sort words.txt -o words.txt
I use printf rather than echo figuring that'll avoid the newline, but the file then reads
apple
cookie
orange
salmon
#newline here
If I just run printf "\norange" >> words.txt orange appears at the bottom of the file, with no newline, ie;
apple
cookie
salmon
orange
This behavior is explicitly defined in the POSIX specification for sort:
The input files shall be text files, except that the sort utility shall add a newline to the end of a file ending with an incomplete last line.
As a UNIX "text file" is only valid if all lines end in newlines, as also defined in the POSIX standard:
Text file - A file that contains characters organized into zero or more lines. The lines do not contain NUL characters and none can exceed {LINE_MAX} bytes in length, including the newline character. Although POSIX.1-2008 does not distinguish between text files and binary files (see the ISO C standard), many utilities only produce predictable or meaningful output when operating on text files. The standard utilities that have such restrictions always specify "text files" in their STDIN or INPUT FILES sections.
Think about what you are asking sort to do.
You are asking it "take all the lines, and sort them in order."
You've given it a file containing four lines, which it splits to the following strings:
"salmon\n"
"cookie\n"
"orange"
It sorts these for you dutifully:
"cookie\n"
"orange"
"salmon\n"
And it then outputs them as a single string:
"cookie
orangesalmon
"
That is almost certainly exactly what you do not want.
So instead, if your file is missing the terminating newline that it should have had, the sort program understands that, most likely, you still intended that last line to be a line, rather than just a fragment of a line. It appends a \n to the string "orange", making it "orange\n". Then it can be sorted properly, without "orange" getting concatenated with whatever line happens to come immediately after it:
"cookie\n"
"orange\n"
"salmon\n"
So when it then outputs them as a single string, it looks a lot better:
"cookie
orange
salmon
"
You could strip the last character off the file, the one from the end of "salmon\n", using a range of handy tools such as awk, sed, perl, php, or even raw bash. This is covered elsewhere, in places like:
How can I remove the last character of a file in unix?
But please don't do that. You'll just cause problems for all other utilities that have to handle your files, like sort. And if you assume that there is no terminating newline in your files, then you will make your code brittle: any part of the toolchain which "fixes" your error (as sort kinda does here) will "break" your code.
Instead, treat text files the way they are meant to be treated in unix: a sequence of "lines" (strings of zero or more non-newline bytes), each followed by a newline.
So newlines are line-terminators, not line-separators.
There is a coding style where prints and echos are done with the newline leading. This is wrong for many reasons, including creating malformed text files, and causing the output of the program to be concatenated with the command prompt. printf "orange\n" is correct style, and also more readable: at a glance someone maintaining your code can tell you're printing the word "orange" and a newline, whereas printf "\norange" looks at first glance like it's printing a backslash and the phrase "no range" with a missing space.
I have a simple sed script and I am replacing a bunch of lines in my application dynamically with a variable, the variable is a list of strings.My function works but does not keep the original indentation.the function deletes the line if it contains the certain string and replaces the line with a completely new line, I could not do a replace due to certain syntax restrictions.
How do I keep my original indentation when the line is replaced
Can I capitalize my variable and remove the underscore on the fly, i.e. the title is a capitalize and underscore removed version of the variableName, the list of items in the variable array is really long so I am trying to do this in one shot.
Ex: I want report_type -> Report Type done mid process
Is there a better way to solve this with sed? Thanks for any inputs much appreciated.
sed function is as follows
variableName=$1
sed -i "/name\=\"${variableName}\.name\" value\=model\.${variableName}\.name options\=\#lists\./c\\{\{\> \_dropdown title\=\"${variableName}\" required\=true name\=\"${variableName}\"\}\}" test
SAMPLE INPUT
{{> _select title="Report Type" required=true name="report_type.name" value=model.report_type.name options=#lists.report_type}}
SAMPLE EXPECTED OUPUT
{{> _dropdown title="Report Type" required=true name="report_type" value=model.report_type.name}}
sample input variable
report_type
Try this:
sed -E "s/^(\s+).*name\=\"(report_type)\.name\" value\=model\.report_type\.name options\=\#lists\..*$/\1\{\{\> \_dropdown title\=\"\2\" required\=true name\=\"\2\"\}\}/;T;s/\"(\w+)_(\w+)\"/\"\u\1 \u\2\"/g" input.txt > output.txt
I used "report_type" instead of ${variableName} for testing as an sed one-liner.
Please change back to ${variableName}.
Then go back to using -i (in addition to -E, which is for extended regex).
I am not sure whether I can do it without extended regex, let me know if that is necessary.
use s/// to replace fine tuned line
first capture group for the white space making the indentation
second capture group for the variable name
stop if that did not replace anything, T;
another s///
look for something consisting of only letters between "",
with a "_" between two parts,
seems safe enough because this step is only done on the already replaced line
replace by two parts, without "_"
\u for making camel case
Note:
Doing this on your sample input creates two very similar lines.
I assume that is intentional. Otherwise please provide desired output.
Using GNU sed version 4.2.1.
Interesting line of output:
{{> _dropdown title="Report Type" required=true name="Report Type"}}
I have a huge text file with strings of a special format. How can i quickly create another file with only strings corresponding to my condition?
for example, file contents:
[2/Nov/2015][rule="myRule"]"GET
http://uselesssotialnetwork.com/picturewithcat.jpg"
[2/Nov/2015][rule="mySecondRule"]"GET
http://anotheruselesssotialnetwork.com/picturewithdog.jpg"
[2/Nov/2015][rule="myRule"]"GET
http://uselesssotialnetwork.com/picturewithzombie.jpg"
and i only need string with "myRule" and "cat"?
I think it should be perl, or bash, but it doesn't matter.
Thanks a lot, sorry for noob question.
Is it correct, that each entry is two lines long? Then you can use sed:
sed -n '/myRule/ {N }; /myRule.*cat/ {p}'
the first rule appends the nextline to patternspace when myRule matches
the second rule tries to match myRule followed by a cat in the patternspace , if found it prints patternspace
If your file is truly huge to the extent that it won't fit in memory (although files up to a few gigabytes are fine in modern computer systems) then the only way is to either change the record separator or to read the lines in pairs
This shows the first way, and assumes that the second line of every pair ends with a double quote followed by a newline
perl -ne'BEGIN{$/ = qq{"\n}} print if /myRule/ and /cat/' huge_file.txt
and this is the second
perl -ne'$_ .= <>; print if /myRule/ and /cat/' huge_file.txt
When given your sample data as input, both methods produce this output
[2/Nov/2015][rule="myRule"]"GET
http://uselesssotialnetwork.com/picturewithcat.jpg"
I've got some source code like the following where I call a function in C:
void myFunction (
&((int) table[1, 0]),
&((int) table[2, 0]),
&((int) table[3, 0])
);
...the only problem is that the function has >300 parameters (it's an auto-generated wrapper for initialising and calling a whole module; it was given to me and I cannot change it). And as you can see: I began accessing the array with a 1 instead of a 0... Great times, modifying all the 300 parameters, i.e. decrasing 300 x the x-coordinate of the array, by hand.
The solution I am looking for is how I could force sed to to do the work for me ;)
EDIT: Please note that the syntax above for accessing a two-dimensional array in C is wrong anyway! Of course it should be [1][0]... (so don't just copy-and-paste ;))
Basically, the command I came up with, was the following:
sed -r 's/(.*)(table\[)([0-9]+)(,)(.*)/echo "\1\2$((\3-1))\4\5"/ge' inputfile.c > outputfile.c
Well, this does not look very intuitive on the first sight - and I was missing good explanations for nearly every example I found.
So I will try to give a detailed explanation on this:
sed
--> basic command
-r
--> most examples you find are using -e; however, the -r parameter (only works with GNU sed) enables extended regular expressions and brings support for the + in a regex. It basically means "one or more matches".
's/input/output/ge'
--> this is the basic replacement syntax. It basically means "replace 'input' by 'output'". The /g is a "global" flag, i.e. sed will replace all occurences and not only the first one. You can add an additional e to execute the result in the bash. This is what we want to do here to handle the calculation.
(.*)
--> this matches "everthing" from the last match to the next match
(table\[)
--> the \ is to escape the bracket. This part of the expression will match Strings like table[
([0-9]+)
--> this one matches numbers with at least one digit, however, it can also match higher numbers with more than only one digit.
(,)
--> this simply matches the comma ,
(.*)
--> and again: the rest of the line
And now the interesting part:
echo "\1\2$((\3-1))\4\5"
the echo is a bash command
the \n (you can use every value from \1 up to \9) is some kind of "variable" for the inputs: \1 will contain the first match, \2 the seconds match, ... --> this helps you to preserve parts of the input string
the $((1+1)) is a simple bash syntax to calculate the value of the term inside the double brackets (in the complete sed command above, the \3 will of course be automatically replaced by the 3rd match, i.e. the 1st part inside the brackets to access the table's cells)
please note that we use quotation marks around the echo content to also be able to process lines with characters like & which would otherwise not work
The already mentioned e of \ge at the end will trigger the execution of the result in the bash. E.g. the first two lines of the example source code in the question would produce the following bash statements:
echo "void myFunction ("
echo " &((int) table[$((1-1)), 0]),"
which is being executed and results in the following output:
void myFunction (
&((int) table[0, 0]),
...which is exatcly what I wanted :)
BTW:
text > output.c
is simple bash syntax to output text (or in this case the sed-processed source code) to a file called output.c.
Good links about this topic are:
sed basics
regular expressions basics
Ahh and one more thing: You can also use sed in the git-Bash on Windows - if you are "forced" to use Windows at work like me ;)
PS: In the meantime I could have easily done this by hand but using sed was a lot more fun ;)
Here's another way you could do it, using Perl:
perl -pe 's/(table\[)(\d+)(,)/$1.($2-1).$3/e' file.c
This uses the e modifier to execute an expression in the replacement. The capture groups are concatenated together but the middle group has 1 subtracted from its value.
This will output to standard output so you can check that it does what you want. When you're happy, you can add the -i switch to overwrite the original file.
So I have a strange question. I have written a script that re-formats data files. I basically create new files with the right column order, spacing, and such. I then unix2dos these files (the program I am formatting these files for is DIPS for windows, and I assume that the files should be ansi). When I go to open the files in the DIPS Program however an error occurs and the file won't open.
When I create the same kind of data file through the DIPS program and open it in note pad, it matches exactly with the data files I have created with my script.
On the other hand if I open the data files that I have created with my script in Kedit first, save them, and then open them in the DIPS program everything works.
My question is what could saving in Kedit possibly do that unix2dos does not?
(Also if I try using note pad or word pad to save instead of Kedit the file doesn't open in DIPS)
Here is what was created using the diff command in unix
"
1,16c1,16
* This file is generated by Dips for Windows.
* The following 2 lines are the Title of this file.
Cobre Panama
Drill Hole B11106-GT
Number of Traverses: 0
Global Orientation is:
DIP/DIPDIRECTION
0.000000 (Declination)
NO QUANTITY
Number of extra columns are: 0
--
* This file is generated by Dips for Windows.
* The following 2 lines are the Title of this file.
Cobre Panama
Drill Hole B11106-GT
Number of Traverses: 0
Global Orientation is:
DIP/DIPDIRECTION
0.000000 (Declination)
NO QUANTITY
Number of extra columns are: 0
18c18
--
440c440
--
442c442
-1
-1
"
Any help would be appreciated! Thanks!
Okay! Figured it out.
Simply when you unix2dos your file you do not strip any space characters in between the last letter in a line and the line break character. When saving in Kedit you do strip the spaces between the last letter in a line and the line break character.
In my script I had a poor programing practice in which I was writing a string like this;
echo "This is an example string " >> outfile.txt
The character count is 32, and if you could see the break line character (chr(10)) the line would read;
This is an example string
If you unix2dos outfile.txt the line looks the same as above but with a different break line character. However when you place the file into Kedit and save it, now the character count is 25 and the line looks like this;
This is an example string
This occurs because Kedit does not preserve spaces at the end of a line. It places the return or line break character at the last letter or "non space" character in a line.
So programs that read literal input like DIPS (i'm guessing) or more widely used AutoCAD scripting will have a real problem with extra spaces before the return character. Basically in AutoCAD scripting a space in a line is treated as a return character. So if you have ten extra spaces at the end of a line it's treated the same as ten returns instead of the one you probably intended.
OH and if this helped you out or though it was good please give me a vote up!
unix2dos converts the line-break characters at the end of each line, from unix line breaks (10) to dos line breaks (13, 10)
Kedit could possible change the encoding of the file (like from ansi to UTF-8)
You can change the encoding of a file with the iconv utility (on a linux box)