The task of sorting matrix columns [closed]

Question

Conditions : There is a square matrix filled with numbers from -10 to 10.

Task : Convert the original matrix so that within each column all negative numbers are always below positive numbers vertically, while respecting their original order in relation to each other.

<?php function squareMatrixToString($squareMatrix) { $result = '<hr>'; $squareMatrixSize = count($squareMatrix); for($i = 0; $i < $squareMatrixSize; $i++) { for($j = 0; $j < $squareMatrixSize; $j++) { $result .= $squareMatrix[$i][$j] . ' '; } $result .= '<br>'; } return $result; } /*** Generate squareMatrix ***/ $squareMatrixSize = 10; $squareMatrix = array(); for($i = 0; $i < $squareMatrixSize; $i++) { for($j = 0; $j < $squareMatrixSize; $j++) { $squareMatrix[$i][$j] = 10 - rand(0, 20); } } echo squareMatrixToString($squareMatrix); // TO DO: echo squareMatrixToString($squareMatrix); ?> //на что хватило for($col = 0; $col < 10; $col++) usort($squareMatrix, $sort = function($a, $b) use ($col){ if($a[$col] === $b[$col]) return 0; return ($a[$col] < $b[$col]) ? 1 : -1; });

@ garjo_099 - Well, you should try to do it yourself even for decency.
@ garjo_099 - Please add code by editing the question, not in the comments.

alexander barakin 56.8k 13 48 172 · Answer 1 · 2016-01-13T00:22:06

So far, I have come to such a simple and concise code.

Work code:

  /** Задача 3 */ function squareMatrixToString($squareMatrix) { $result = '<hr><table style="text-align: center">'; $squareMatrixSize = count($squareMatrix); for($i = 0; $i < $squareMatrixSize; $i++) { $result .= '<tr>'; for($j = 0; $j < $squareMatrixSize; $j++) { $result .= '<td>'.$squareMatrix[$i][$j] . '</td>'; } $result .= '</tr>'; } return $result .= '</table>'; } /*** Generate squareMatrix ***/ $squareMatrixSize = 10; $squareMatrix = array(); for($i = 0; $i < $squareMatrixSize; $i++) { for($j = 0; $j < $squareMatrixSize; $j++) { $rand = 10 - rand(0, 20); $squareMatrix[$i][$j] = $rand; } } echo squareMatrixToString($squareMatrix); // TO DO: $tmp = []; for($col = 0; $col < $squareMatrixSize; $col++) { $plus = []; $minus = []; for($row = 0; $row < $squareMatrixSize; $row++) { $num = $squareMatrix[$row][$col]; if($num >= 0) $plus[] = $num; else $minus[] = $num; } rsort($minus); $continueRow = count($plus); for($row = 0; $row < $continueRow; $row++) $squareMatrix[$row][$col] = array_shift($plus); $toEnd = count($minus); for($row = $continueRow; $row < $squareMatrixSize; $row++) $squareMatrix[$row][$col] = array_shift($minus); } echo squareMatrixToString($squareMatrix);

I couldn’t remove the necessary lines from my code to make it work, but I wrote something of my own :-D
I would not do it myself until I did not calm down, and your code did not solve the task and, after deleting the lines you wrote, it didn’t do what was necessary.
in each column, the positive numbers remain in the same order as before the sorting, and the negative ones line up in descending order immediately below the positive ones. Wasn’t that what the goal was?
or just stupidly had to arrange the negative under the positive, everywhere observing the original order?
right now, I can correct it ... after all, your code doesn’t meet your requirements either)))

Answer 2 · 2016-01-12T21:10:44

The solution is straight to the forehead (non-optimized):

 function squareMatrixToString($squareMatrix) { $result = '<table>'; $squareMatrixSize = count($squareMatrix); for($i = 0; $i < $squareMatrixSize; $i++) { $result .= '<tr>'; for($j = 0; $j < $squareMatrixSize; $j++) { $result .= '<td>'; $result .= $squareMatrix[$i][$j] . ' '; $result .= '</td>'; } $result .= '</tr>'; } $result .= '</table>'; $result .= '<hr>'; return $result; } /*** Generate squareMatrix ***/ $squareMatrixSize = 10; $squareMatrix = array(); for($i = 0; $i < $squareMatrixSize; $i++) { for($j = 0; $j < $squareMatrixSize; $j++) { $squareMatrix[$i][$j] = 10 - rand(0, 20); } } echo squareMatrixToString($squareMatrix); $arrSorted = []; for ($i = 0; $i < $squareMatrixSize; ++$i) { $tmp = []; for($j = 0; $j < $squareMatrixSize; $j++) { array_push($tmp,$squareMatrix[$j][$i]); } $plus = array_filter($tmp, function($var){ return $var >= 0; }); $minus = array_filter($tmp, function($var){ return $var < 0; }); array_push($arrSorted, array_merge($plus, $minus)); } $squareMatrix = []; for ($i = 0; $i < $squareMatrixSize; ++$i) { $tmp = []; for($j = 0; $j < $squareMatrixSize; $j++) { array_push($tmp, $arrSorted[$j][$i]); } array_push($squareMatrix, $tmp); } echo squareMatrixToString($squareMatrix);

http://phpfiddle.org/main/code/x0dr-jbzy

UPD: More concise solution:

 //******************************************** // TODO $result = []; for($i = 0; $i < $squareMatrixSize; $i++) { $col = array_column($squareMatrix, $i); $plus = array_filter($col, function($var){ return $var >= 0; }); $minus = array_filter($col, function($var){ return $var < 0; }); for($j = 0; $j < $squareMatrixSize; $j++) { $result[$j][$i] = $merge[$j]; } } echo squareMatrixToString($result); // //***********************************************

http://phpfiddle.org/main/code/vg6x-q9v5

@ garjo_099 well, I thought I should also sort in ascending order .... well, then comment out / delete the sort($plus, SORT_NUMERIC); $plus = array_values($plus); lines sort($plus, SORT_NUMERIC); $plus = array_values($plus);
@ garjo_099 wanna say this doesn't work: phpfiddle.org/main/code/g84f-z5vm ???
@ garjo_099 I probably was inattentive at night when I read the question ..... I corrected the answer and links to the test.
I think now everything is working as it should ..... because your published answer does not seem to correspond to your demand either)

The task of sorting matrix columns [closed]

Closed due to the fact that the essence of the question is incomprehensible by the participants Vladimir Martianov , user194374, Abyx , LEQADA , Saidolim Jan 13 '16 at 17:41 .

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