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Index › Programming Questions & Help › Syntax Questions › search string for word
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search string for word (Read 1756 times)
drew
search string for word
Feb 11th, 2009, 5:05pm  
hello all

I am a semi newbie to processing but love the program and want to know more.

I want to have processing search a string (and eventually multiple strings) for certain words then add that count to an int variable.  What kind of syntax would I use for that?

Ive searched around for how to do this but I'm not sure how to word it.

Thanks in advance for your help
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JohnG
Re: search string for word
Reply #1 - Feb 11th, 2009, 6:24pm  
Code:
String foo="one two three four";
String bar="three four five";

if(foo.indexOf("two")>=0)
{
  println("Foundin foo!");
}

if(bar.indexOf("two")>=0)
{
  println("Found in bar!");
}
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drew
Re: search string for word
Reply #2 - Feb 11th, 2009, 7:34pm  
That is awesome

Thank you JohnG
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drew
Re: search string for word
Reply #3 - Feb 11th, 2009, 8:10pm  
What if I wanted to count the number of times that word appears in the string?
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JohnG
Re: search string for word
Reply #4 - Feb 11th, 2009, 9:00pm  
Code:
String foo="one two one two one";
int index=0;
int count=0;
while(foo.indexOf("two",index)>=0)
{
  count++;
  index=foo.indexOf("two",index)+3; //search from after this occurance next time...
}
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PhiLho 
Re: search string for word
Reply #5 - Feb 12th, 2009, 11:15am  
Another way is to split() (or using splitTokens()) the string (hoping it isn't megabytes in size!) then loop on the resulting array: for each array entry, get(word) on a HashMap. If null, put(word, 1). If not, put(word, previousCount + 1)
The HashMap will store the whole list of words as keys, with their count as value.

JohnG's method is perfect if you want the count of a precise word (or set of words) but a bit slow for a large set of words (as you walk the string for each occurrence), and you must know the words to search.
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WWW  
drew
Re: search string for word
Reply #6 - Feb 13th, 2009, 4:43pm  
How could I convert my Array into a Hashmap????
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PhiLho 
Re: search string for word
Reply #7 - Feb 13th, 2009, 5:12pm  
Which array?
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drew
Re: search string for word
Reply #8 - Feb 13th, 2009, 5:36pm  
ok sorry, here is what I have in my setup:

Code:

void setup() {
  size(500, 200);
  background(0);
  noLoop();
  smooth();
  // load feed
  //feedurl="http://en-us.fxfeeds.mozilla.com/en-US/firefox/headlines.xml";
  feedurl="http://uncammac.wordpress.com/feed/";
  println("Loading feed: "+feedurl);
  feed=new FeedReader(feedurl);

  // print feed data
  println("Feed: "+feed.title);
  println("------------------------------");
  println("Description: "+feed.description);
  println("Number of entries: "+feed.numEntries);
  println("------------------------------");

  // print feed entries
  for(int i=0; i<feed.numEntries; i++) {
    println(i+": "+feed.entry[i]);
    // feed.entry[] stores strings url, description, and title
  }
}


What is happening is that I am reading RSS Feeds through a FeedReader Class.  The feeds are stored in the array feed.entry[] but the data inside are strings.  I want to search a particular array spot (and the strings inside them) for a particular word then add the count of that word to a varible.  I see how I can use splitTokens() to split a string but dont know how to do it from within an array.

Thx again for your help
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PhiLho 
Re: search string for word
Reply #9 - Feb 13th, 2009, 5:48pm  
Ah, so you need actually to find the number of occurrences of a given string inside a bigger string.
My hash map solution isn't really suited, then.
I have another brute force solution, with advantage of simplicity and no loop:
Code:
String s = "Inside tags, you will find multiple pieces of content.";

String[][] m = matchAll(s, "(e)");
println("Found " + m.length + " e's in the sentence");


Replace "(e)" with "(tag to search)" and s by feed.entry[i]) and you have your number.
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drew
Re: search string for word
Reply #10 - Feb 13th, 2009, 8:26pm  
When I try

Code:

  String[][] m = matchAll(feed.description[1], "(e)");
  println("Found " + m.length + " e's in the sentence");


i get error:

the type of expression must be an array but it resolved to String

when I try
Code:

  String[][] m = matchAll(feed.entry[1], "(e)");
  println("Found " + m.length + " e's in the sentence");


i get error:

The Mechod matchAll(String,String) in the type PApplet is not applicable for the arguments (my_file_name.FeedEntry, String)

im not sure what I am doing wrong
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PhiLho 
Re: search string for word
Reply #11 - Feb 13th, 2009, 10:32pm  
I don't know what your feed class looks like.
But from your code snippet, there is only one feed.description, so you cannot use [i] on it.
And feed.entry[i] looks like a class too, so you need to get a specific field inside, like feed.entry[i].description or similar.
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drew
Re: search string for word
Reply #12 - Feb 14th, 2009, 7:25pm  
feed.entry[i].description is exactly what I was looking for.  Now Im searching for those strings fine and everything is working.  Thank you sooo much for your help.

youre the best
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