awk accepts data from stdin by default, printing text to stdout.Default input and output delimiters for awk:FS: Enter field delimiter, default space.RS: Enter line delimiter, default \ n.OFS: Output field delimiter, default space.ORS: Output line delimiter, default \ n.Example: Make multiple rows into a row by changing the default built-in variableFile.txt (the number of information bars for each person is not sure, the distinction is a blank line)Pedestrian ArmorTel: 13777707771Mobile: 010-1234
(INT) A + 1; else return (INT) ;}
C. Resize. CC: alphainfo OFS [Len]; this sentence is changed to: alphainfo * OFS = new alphainfo [Len]; of course, delete [] OFS is added after the same scope;
After changing the above several points, you can run it. Run demo. m to check the effect.
From: http://blog.csdn.net/pozen/article/details/7023742
3. The next ste
Use of awk:Awk:aho,kernighan,weinbergerNew Awk:nawkGawk,awk# awk [option] ' script ' file ...# awk [option] ' Pattern {action} ' file ...The output of awk:First, printPrint ITEM1,ITEM2,...Points:1. Separate items using ', ', separated by the specified delimiter when output, and the default input and output delimiter is a space2. The output item can be a string or numeric value, the current record field ($), a variable, or an expression of awk, and the value will be converted to a string before o
.
OFMT
The output format of the number (default value: %. 6g ).
OFS
Delimiter of the output field (the default value is a space ).
ORS
The output record delimiter (the default value is a line break ).
RLENGTH
The length of the string matched by the match function.
RS
Record separator (a line break by default ).
RSTART
The first position of the string matched by the match function.
Variable
Description
$ N
The Nth field of the current record. The fields are separated by FS.
$0
Complete input records.
ARGC
The number of command line parameters.
ARGIND
Location of the current file in the command line (starting from 0 ).
ARGV
Array containing command line parameters.
CONVFMT
Number conversion format (default value: %. 6g)
ENVIRON
Environment Variable join array.
ERRNO
Descri
install the option, copies the file, and then performs other settings. Save the compressed version of the setup program as a resource in the installer. The installer only needs to re-create the binary resource of the setup program and write it back to the disk. decompress the package and start it with a new process. It is not difficult to save and read/write binary resources-the processing details and code have been described earlier in this article.Since Windows 95, each Windows platform has a
introduce them from shell variables.
AWK variable
Number of current records of NR (Statistics after all files are connected)
Number of current records of FNR (only statistics of the current file, not all)
The default delimiter of the FS Field is a consecutive space or tab. You can use multiple symbols as the separator-F [:/]
The default delimiter of OFS output characters is space.
[OFS example]
# Aw
the currently processed file awk '{if (ARGIND = 1) {print $1} if (ARGIND = 2) {print $2} 'aaa.txt bbb.txt # first scans the aaa file and then the bbb File
Number of records read by NR awk 'nr = 1, NR = 5 {print} 'aaa.txt # displays 1 to 5 rows of aaa.txt files
FNR current file records awk 'nr = FNR {print "a"} NR> FNR {print "B"} 'a.txt B .txt # input file a.txt and B .txt, when scanning a.txt, there must be NR = FNR; # After scanning B .txt, FNR starts to count from 1, while NRIS connected to
pointer to the structure of a file type BIO_METHOD. Its function implementation is as follows:
BIO_METHOD * BIO_s_file (void)
{
Return ( methods_filep );
}
In fact, from this structure, we can see the first class of BIO implementation, that is, all BIO actions are based on its BIO _
METHOD (the first parameter) to determine its action and behavior, so as to realize BIO polymorphism for various types
.
In the file type, use BIO_read and BIO_write described earlier to read the underlying file dat
a treasure. Awk explanation: read each file specified on the command (if not, the standard input), read a record at a time (line) then the command specified for each line of application .... | Awk '{print some-stuff}' |... sed and awk are a big topic that cannot be mentioned at a moment. Therefore, the original book only talked about a part of it. Awk '{print $1}' print the first program awk '{print $1, $5}' print 2-5 fields awk '{print $1, $ NFS} 'print 1 till the end of the print. Do not pres
where the current record is located. 4. Set the output field separator (OFS usage) [chengmo @ localhost ~] $ Awk 'in in {FS = ":"; OFS = "^"}/^ root/{print FNR, $1, $ NF} '/etc/passwd1 ^ root ^/bin/bash OFS set the default field separator 5. Set the output line record separator (ORS usage) [chengmo @ localhost ~] $ Awk 'in in {FS = ":"; ORS = "^"} {print FNR, $1
line breaks, the escape sequence \ n is required. 2. The size of the built-in variable name in the awk can be used in the expression and can be reset. Www.2cto.com variable name variable meaning ARGC command line variable count ARGV command line variable array FILENAME currently input file name NF number of currently recorded domains NR so far all input file records FNR so far number of records of the current file FS input domain delimiter, it is a space by default. You can also use the-F optio
. Out. I added the following code at the beginning of the program:
1 # include 2 # include 34 class dostream: public STD: ostream {5 public:6 dostream (): OFS ("cout.txt "){}78 template 9 dostream operator 10 STD: cout 11 OFS 1213 return * this;14}1516 private:17 STD: ofstream OFS;18 };1920 dostream dout;2122 # define cout dout
The landlord continues to ask:How
statement: Execute next in the first {}, which means to skip all subsequent statements and re-read a new record for matching.
[[emailprotected]awk]#awk‘NR==FNR{print$0;next}{print$0}‘cdc1c2c3c4d5d6d7d8[[emailprotected]awk]#awk‘NR==FNR{print$0}{print$0}‘cdc1c1c2c2c3c3c4c4d5d6d7d8[[emailprotected]awk]#
OFS: delimiter of the output field. The default value is space.
ORS: Specifies the output line delimiter. The default value is a line break.
[[Email
-th row, multiplied by 3 to the 3rd rowM.row(3) = M.row(3) + M.row(5)*3;// now copy the 7-th column to the 1-st column// M.col(1) = M.col(7); // this will not workMat M1 = M.col(1);M.col(7).copyTo(M1);// create a new 320x240 imageMat img(Size(320,240),CV_8UC3);// select a ROIMat roi(img, Rect(10,10,100,100));// fill the ROI with (0,255,0) (which is green in RGB space);// the original 320x240 image will be modifiedroi = Scalar(0,255,0);
Due to the additionalDatastartAndDataendMembers, it is po
A Basic introduction1.awk:Awk is a powerful text analysis tool that is irreplaceable in the processing of text files and generating reports. Awk considers text files to be structured, which defines each input row as a single record, each string in the row is defined as a field (segment), and the domain and domain are split using a delimiter.2. Functions: Flow control, mathematical operations, Process Control, built-in variables and functions, loops and judgments3. Working principle:Awk makes eac
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