I have a script which reads a list of integers from arguments and stores into a list then reverses its order.
I am trying to look for a way to check if the input argument contains a letter so I can halt the program and throw a error message. Then exit the script.
How can I check if a certain string has a letter? This letter can be uppercase or lowercase.
Try
regexp {[[:alpha:]]} $string
returns 1 if there is a letter, 0 otherwise.
Documentation:
regexp,
Syntax of Tcl regular expressions
Related
Hi I have redis sets with members
"{id:3,url:'Twitter.com'}"
"{id:1,url:'Facebook.com'}"
"{id:2,url:'Google.com'}"
How can I use scan command to search member that url starts with F
I've tried SSCAN xurl 0 MATCH *url:'F?'* but it said invalid argument(s)
Can anyone help me?
invalid argument(s) returned since the closed quotes in your input followed by non space characters (*). That's not allowed.
if the input string contains single quotes, you can put them into double quotes like this:
SSCAN xurl 0 MATCH "*url:'F*'*"
Or:
SSCAN xurl 0 MATCH '*url:\'F*\'*'
BTW: the character ? in match option means there's a single character at that place. Replace it with * will be fine. Redis match patterns
I'm trying to figure out the base regex to capture the middle of a google url out of a sql database.
For example, a few links:
https://www.google.com/cars/?year=2016&model=dodge+durango&id=1234
https://www.google.com/cars/?year=2014&model=jeep+cherokee+crossover&id=6789
What would be the regex to capture the text to get dodge+durango , or jeep+cherokee+crossover ? (It's alright that the + still be in there.)
My Attempts:
1)
\b[=.]\W\b\w{5}\b[+.]?\w{7}
, but this clearly does not work as this is a hard coded scenario that would only work like something for the dodge durango example. (would extract "dodge+durango)
2) Using positive lookback ,
[^+]( ?=&id )
but I am not fully sure how to use this, as this only grabs one character behind the & symbol.
How can I extract a string of (potentially) any length with any amount of + delimeters between the "model=" and "&id" boundaries?
seems like you could use regexp_replace and access match groups:
regexp_replace(input, 'model=(.*?)([&\\s]|$)', E'\\1')
from here:
The regexp_replace function provides substitution of new text for
substrings that match POSIX regular expression patterns. It has the
syntax regexp_replace(source, pattern, replacement [, flags ]). The
source string is returned unchanged if there is no match to the
pattern. If there is a match, the source string is returned with the
replacement string substituted for the matching substring. The
replacement string can contain \n, where n is 1 through 9, to indicate
that the source substring matching the n'th parenthesized
subexpression of the pattern should be inserted, and it can contain \&
to indicate that the substring matching the entire pattern should be
inserted. Write \ if you need to put a literal backslash in the
replacement text. The flags parameter is an optional text string
containing zero or more single-letter flags that change the function's
behavior. Flag i specifies case-insensitive matching, while flag g
specifies replacement of each matching substring rather than only the
first one
I may be misunderstanding, but if you want to get the model, just select everything between model= and the ampersand (&).
regexp_matches(input, 'model=([^&]*)')
model=: Match literally
([^&]*): Capture
[^&]*: Anything that isn't an ampersand
*: Unlimited times
I would like to write a regular expression that starts with the string "wp" and ends with the string "php" to locate a file in a directory. How do I do it?
Example file: wp-comments-post.php
This should do it for you ^wp.*php$
Matches
wp-comments-post.php
wp.something.php
wp.php
Doesn't match
something-wp.php
wp.php.txt
^wp.*\.php$ Should do the trick.
The .* means "any character, repeated 0 or more times". The next . is escaped because it's a special character, and you want a literal period (".php"). Don't forget that if you're typing this in as a literal string in something like C#, Java, etc., you need to escape the backslash because it's a special character in many literal strings.
Example:
ajshdjashdjashdlasdlhdlSTARTasdasdsdaasdENDaknsdklansdlknaldknaaklsdn
1) START\w*END
return: STARTasdasdsdaasdEND - will give you words between START and END
2) START\d*END
return: START12121212END - will give you numbers between START and END
3) START\d*_\d*END
return: START1212_1212END - will give you numbers between START and END having _
do you know if the following statement is guaranteed to be true by one of the fortran 90/95/2003 standards?
"Suppose a read statement for a character variable is given a blank line (i.e., containing only white spaces and new line characters). If the format specifier is an asterisk (*), it continues to read the subsequent lines until a non-blank line is found. If the format specifier is '(A)', a blank string is substituted to the character variable."
For example, please look at the following minimal program and input file.
program code:
PROGRAM chk_read
INTEGER, PARAMETER :: MAXLEN=30
CHARACTER(len=MAXLEN) :: str1, str2
str1='minomonta'
read(*,*) str1
write(*,'(3A)') 'str1_start|', str1, '|str1_end'
str2='minomonta'
read(*,'(A)') str2
write(*,'(3A)') 'str2_start|', str2, '|str2_end'
END PROGRAM chk_read
input file:
----'input.dat' content is below this line----
yamanakako
kawaguchiko
----'input.dat' content is above this line----
Please note that there are four lines in 'input.dat' and the first and third lines are blank (contain only white spaces and new line characters). If I run the program as
$ ../chk_read < input.dat > output.dat
I get the following output
----'output.dat' content is below this line----
str1_start|yamanakako |str1_end
str2_start| |str2_end
----'output.dat' content is above this line----
The first read statement for the variable 'str1' seems to look at the first line of 'input.dat', find a blank line, move on to the second line, find the character value 'yamanakako', and store it in 'str1'.
In contrast, the second read statement for the variable 'str2' seems to be given the third line, which is blank, and store the blank line in 'str2', without moving on to the fourth line.
I tried compiling the program by Intel Fortran (ifort 12.0.4) and GNU Fortran (gfortran 4.5.0) and got the same result.
A little bit about a background of asking this question: I am writing a subroutine to read a data file that uses a blank line as a separator of data blocks. I want to make sure that the blank line, and only the blank line, is thrown away while reading the data. I also need to make it standard conforming and portable.
Thanks for your help.
From Fortran 2008 standard draft:
List-directed input/output allows data editing according to the type
of the list item instead of by a format specification. It also allows
data to be free-field, that is, separated by commas (or semicolons) or
blanks.
Then:
The characters in one or more list-directed records constitute a
sequence of values and value separators. The end of a record has the
same effect as a blank character, unless it is within a character
constant. Any sequence of two or more consecutive blanks is treated as
a single blank, unless it is within a character constant.
This implicitly states that in list-directed input, blank lines are treated as blanks until the next non-blank value.
When using a fmt='(A)' format descriptor when reading, blank lines are read into str. On the other side, fmt=*, which implies list-directed I/O in free-form, skips blank lines until it finds a non-blank character string. To test this, do something like:
PROGRAM chk_read
INTEGER :: cnt
INTEGER, PARAMETER :: MAXLEN=30
CHARACTER(len=MAXLEN) :: str
cnt=1
do
read(*,fmt='(A)',end=100)str
write(*,'(I1,3A)')cnt,' str_start|', str, '|str_end'
cnt=cnt+1
enddo
100 continue
END PROGRAM chk_read
$ cat input.dat
yamanakako
kawaguchiko
EOF
Running the program gives this output:
$ a.out < input.dat
1 str_start| |str_end
2 str_start| |str_end
3 str_start| |str_end
4 str_start|yamanakako |str_end
5 str_start| |str_end
6 str_start|kawaguchiko |str_end
On the other hand, if you use default input:
read(*,fmt=*,end=100)str
You end up with this output:
$ a.out < input.dat
1 str1_start|yamanakako |str1_end
2 str2_start|kawaguchiko |str2_end
This Part of the F2008 standard draft probably treats your problem:
10.10.3 List-directed input
7 When the next effective item is of type character, the input form
consists of a possibly delimited sequence of zero or more
rep-char s whose kind type parameter is implied by the kind of the
effective item. Character sequences may be continued from the end of
one record to the beginning of the next record, but the end of record
shall not occur between a doubled apostrophe in an
apostrophe-delimited character sequence, nor between a doubled quote
in a quote-delimited character sequence. The end of the record does
not cause a blank or any other character to become part of the
character sequence. The character sequence may be continued on as many
records as needed. The characters blank, comma, semicolon, and slash
may appear in default, ASCII, or ISO 10646 character sequences.
OK So i am confused (obviously)
I'm trying to return rows (from Oracle) where a text field contains a complete word, not just the substring.
a simple example is the word 'I'.
Show me all rows where the string contains the word 'I', but not simply where 'I' is a substring somewhere as in '%I%'
so I wrote what i thought would be a simple regex:
select REGEXP_INSTR(upper(description), '\bI\b') from mytab;
expecting that I should be detected with word boundaries. I get no results (or rather the result 0 for each row.
what i expect:
'I am the Administrator' -> 1
'I'm the administrator' -> 0
'Am I the administrator' -> 1
'It is the infamous administrator' -> 0
'The adminisrtrator, tis I' -> 1
isn't the /b supposed to find the contained string by word boundary?
tia
I believe that \b is not supported by your flavor of regex :
http://download.oracle.com/docs/cd/B19306_01/appdev.102/b14251/adfns_regexp.htm#i1007670
Therefore you could do something like :
(^|\s)word(\s|$)
To at least ensure that your "word" is separated by some whitespace or it's the whole string.
Oracle doesn't support word boundary anchors, but even if it did, you wouldn't get the desired result: \b matches between an alphanumeric character and a non-alphanumeric character. The exact definition of what an alnum is differs between implementations, but in most flavors, it's [A-Za-z0-9_] (.NET also considers Unicode letters/digits).
So there are two boundaries around the I in %I%.
If you define your word boundary as "whitespace before/after the word", then you could use
(^|\s)I(\s|$)
which would also work at the start/end of the string.
Oracle native regex support is limited. \b or < cannot be used as word delimiters. You may want Oracle Text for word search.