Programming :: Perl Beginner - Can't Get PerlMagick To Read Filename From Array Element?
Aug 21, 2010
it's been a while since I logged on here! I've been trying my hand at a little perl and have hit a brick wall.I'm using the Imagemagick module to manipulate some images. I can get the following to work without issue:
I'm reading "OReilly Learning Perl 5th Edition", and there are such words:Code:You can use an array element like $fred[2] in every place? where you could use any other scalavariable like $fred.At the bottom of the page, it explains the ? like this:Code:The most notable exception is that the control variable of a foreach loop, which you?ll see later in this chapter, must be a simple scalar.Since Perl has the save-and-restore mechanism for the control variable, why an array element can't be used as the control variable
I have a directory of orchestral music .ogg files from a family member. Each track is from a different artist and the CDDB entry adds a ":" character after the artist name in the track title.
I would like to parse file names in any given directory and search for the string Code: Select all: and replace it with Code: Select all_ According to this post on stackoverflow, I can use Perl to accomplish this task. I've tried Code: Select allperl -i.bak -pe 's/:/_/' but since I am still learning Perl I'm probably commiting a PEBKAC error.
How would I go about solving this issue with regular expressions using Perl?
I tried to look for this, but there are so little of perl on internet: Code: @array = [$title, $description, $pubDate, $link]; push(@feeds1, $array);
I am trying to create a 2 D array by PUSH, so the output would look like: ([ $title, $description, $pubDate, $link ], [ $title, $description, $pubDate, $link ], [ $title, $description, $pubDate, $link ], [ $title, $description, $pubDate, $link ]...etc )
I have an array called @logons. How can I step thru the array and split the fields? This is what I have so far, but doesnt work. I got the feeling I the split statement syntax is incorrect.
Code:
print @logons; foreach my $logons(@logons){ ($userid, $ip) = split(',',$logons);
[code]....
Update: Appears the data in @logons has a column header from the mysql query which I used to populate it with. So that code which I was testing does indeed work.
So I need everything between each name, but I am not guaranteed that each time I match a name that I will have the same amount of lines, so I do a range pattern search line this to get all lines, no matter if there is 5 or 10 or 15. I simply do a loop that goes through the whole array until I hit the match, and this is my search pattern.
This works perfectly... until I hit the end and it doesn't get its final pattern match because it's at the end and there is no next entry with a (Address) line. So as a 'hack', I ended up inserting a final scalar at the end of the array that just says (Address) so it knows it's at the end. Ideally though, I'd like to do an "or" statement that says search for Address || return true if I hit the end of the array. How would I match on "End Of Array" essentially?
I am in need of some syntax help. I'm trying to figure out how to store and retrieve an array out of a hash of hashes. For this example, I'm trying to access the city list for a particular state for a particular country. I understand I could do a join and split on the hash key to combine Country and State, but trying to keep things separated.The code I have gets in all the information for the Countries, and states, and gets the list of cities together, no problem. I store all the city names in an array, then make an anonymous pointer to the array for the hash, like this - $MY_CITIES{$COUNTRY}{$STATE} = [@CITIES]I believe that syntax is correct, or is it? What I'd like to do is I need to cycle through every hash to find if a city exists or not. If it exists in 3 states, then it should print 3 times. Here is the code block to search -
Code: for $COUNTRY (@LIST_OF_COUNTRIES) { for $STATE ( keys %MY_CITIES{$COUNTRY){$STATE} ) {
I have an array ch and I want to increment each element in my array for the following if statement. I'm not sure I have the right array increment syntax but I have tried it in different ways ant it doesn't seem to work.
I tried ch[$1]++, ch[$1]+1, ch[$1++], ch[$1]+=1, ch[$1]=ch[$1]+1 none of these seem to work. # while loop reading from read.txt for check list 1 - 15 for i in `seq 15` do a=`grep "${cl[$i]}" $file` status=$? if [[ $status = 0 ]]; then echo -n -e "1 " let ch[$i+1] let k++ else echo -n -e "0 " fi done for l in `seq 20` do echo -n -e "${ch[$l]} " done
test=(1 2 3 4 5) for car in ${test[@]} do echo "Element : $car"
[code]....
if variable $car equals 1, new element is added "6" to an array. But i don't know why when i am printing all elements of this array (echo "Element : $car") this element ("6") is not mentioned, but if i make a command which check an amount of contained elements by array it will be 6 elements.
I am writing a script that involves reading the content of a file present in a directory and/or its sub directory. I know readdir returns all the files & DIR names in a directory but how to check weather readdir is returning a file or a directory
I am trying to make a perl script which reads data from a file and parse it. The data in the file has the following syntax
Code: Device Physical Name : Not Visible Device Symmetrix Name : 1234 Device Serial ID : N/A Attached BCV Device : N/A Device Capacity
[Code]...
Each unique record starts with "Device Physical Name". So, I have a set of records within "Device Physical Name". I want to read this set of records starting from "Device Physical Name" and ends up till next "Device Physical Name". Offcourse FS is ":", and I just want to print/or later put info in a csv file.
PI'm trying to write a script to list all open ports in the MINIUNPND chain in iptables and use the procotol, port and destination ip to open ports on another router using upnpc.Here is the output of iptables -L MINIUPNPD
No matter what i do i cant seem to remove the first 4 characters from the MYPROT array to leave only the digits. Also i cant seem to read the array back???
I thought it would simply be a loop reading each line and passing the fields in variables, executing upnpc commands i need then moving to the next line of the file until it reached the EOF.
I am looking for an easy way to convert any given maze.txt of any size to a internal array of strings(dynamically allocated). Important is that dimensions of the maze (row, col) shouldn't be written by the user instead they have to be somehow read from the file. This is not my homework assignment! It is a small part of a project that i never dealt with. I never read files to C string.... I made it for specific maze dimensions, but want it to work with any given .txt file.
How can we convert a dynamic library (filename.so) to a static library (filename.a) using gnu gcc . Can we get a static library form a dynamic library . I saw a few post in which the conversion form a static library to a dynamic library is mentioned but, unfortunately, not the other way.
The below snippet works fine until I use strict. Then it dies with the following error: uote:Can't use string ("html") as an ARRAY ref while "strict refs" in use at ./filetest3 line 18.I want to create @lists based on the $scalars in @type. However, "my @$ext = ()"; and push (@$ext, @files); do not play nice with strict. How do I get around this?Quote:
Alright, so I have been trying to resolve this issue for awhile, but now feel like help is very necessary.I have a 128(by)128(by)128 array in a MAT file, and am using the following MATLAB script to convert it to a DAT file:
I just learn perl script.May i know how to simplify the code below especially in the red color part? i saw some examples in internet, they use "next" command.