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Answer 1

A:

split it into an array of words using the php-function explode. Then use two nested loops. The outer one (i) goes through the array-indicies (0..count(array)-1) and is about the first word in the output line. The inner loop (j) goes from i+1 to the length of the array. Then inside the inner loop, you have to output the words from i to j-1. Use implode to do that. Use it on a subarray of the word array from i to j-1. You can get it using array_slice

Christian 2010-05-07 08:05:10

Answer 2

+8 A:

Here's an example:

$sentence = 'Today is a great day.';

// Only leave "word" characters and whitespace
$sentence = preg_replace('/[^\w\s]+/', '', strtolower($sentence));

// Tokenize
$tokens = explode(' ', $sentence);

for($i = 0; $i < count($tokens); $i++) {
    for($j = 1; $j <= count($tokens) - $i; $j++) {
        echo implode(' ', array_slice($tokens, $i, $j)) . "<br />";
    }
}

Output:

today
today is
today is a
today is a great
today is a great day
is
is a
is a great
is a great day
a
a great
a great day
great
great day
day

Brian McKenna 2010-05-07 08:08:40

+1 Easy to read and understand, i.e. not over-engineered :) This would, however, provide a great foundation for a game of code golf.

jensgram 2010-05-07 08:14:30

Brilliant! Thanks.

Eric Sim 2010-05-07 08:43:05

You might want to benchmark this with somewhat longer strings though. `array_slice` does not come cheap.

Gordon 2010-05-07 08:49:43

@jensgram feel free to initiate such a game :)

salathe 2010-05-07 09:21:35

@salathe Hmmm, yeah. Tomorrow, maybe :)

jensgram 2010-05-07 11:01:33

@jensgram: aww, not everyone is around at the weekend :(

salathe 2010-05-07 11:09:24

Answer 3

A:

Recursive approach:

function iterate($words) {
    if(($total = count($words)) > 0) {
        $str = '';
        for($i = 0; $i < $total; $i++ ) {
            $str .= ' ' . $words[$i];
            echo $str . PHP_EOL;
        }
        array_shift($words);
        iterate($words);
    }
}

$text = "Today is a great day.";
$words = str_word_count($text, 1);
iterate($words);

The above will only consider words. It will not remove duplicates. Numbers are not words and punctuation ain't either. With the given test sentence of five words, the recursive approach performs neglectably faster than the array_splice solution. However, this increases significantly with each additional word. A quick benchmark on my machine with a ten word sentence finished in almost half the time.

^{Disclaimer: Isolated Benchmarks depend on a number of factors and may produce different results on different machines. If anything, they can give an indicator about code performance (often in the realms of micro-optimzations), but nothing more.}

Gordon 2010-05-07 08:21:03

Answer 4

A:

$phrase = 'Today is a great day';
$pieces = explode(' ', strtolower($phrase));
$sets = array();
for ($i=0; $i<count($pieces);$i++) {
    for ($j=0; $j<count($pieces);$j++) {
        if ($i<=$j)
            $sets[$i][] = $pieces[$j];
    }
}
print "<ul>";
foreach($sets as $set) {
    while(count($set) > 0) {
        print "<li>" . implode(' ', $set) . "</li>\n";
        array_pop($set);
    }
}
print "</ul>";

Result:

today is a great day
today is a great
today is a
today is
today
is a great day
is a great
is a
is
a great day
a great
a
great day
great
day

artlung 2010-05-07 08:25:56

Answer 5

A:

Does this works for letter of a sentence, too? Can you give the code?

epitaph 2010-08-24 18:41:23

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phrase split algorithm in PHP

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