PHP - Help In Translating Pseudo Code Of Algorithm To Php From A Research Paper.
I'm helping a friend in developing a project for our alma mater. And its based on this paper: An Enhanced Indoor Positioning Method Based on Wi-Fi RSS Fingerprinting So far 80% of the web app is finished except for the algorithm (We have no experience with algorithms to source code translations) that needs to be implemented in the website. Inside this paper there is this algorithm that the proponents of the research used. (attached as screenshot). The algorithm was converted to code by using MATLAB, but we are trying to use PHP with our project. Based on the pseudo code the calculation of the Euclidean Distance is the core of it. Can anyone help us with the translation just to get it started.
Similar TutorialsHoping someone can help me on this, but I had some help on getting this code (or part of it) to finally work the way I wanted it, however, there are a few end-user issues with it now. What this code does is disables the user(s) from posting any kind of links (www.example.com or example.com). However, now I'm trying to....expand it a little I guess. Here is the current code: Code: [Select] if (stristr($pagetext, 'http://') OR stristr($pagetext, 'www.') OR stristr($pagetext,'@') OR stristr($pagetext, '[URL') OR stristr($pagetext, '[url') OR stristr($pagetext, '[IMG') OR stristr($pagetext, '[img') OR preg_match("#[a-z0-9]([-a-z0-9]+)?(\.[a-z]{2,3})?(\.[a-z]{2,4})#i", $pagetext)) { more code here } Now, I KNOW what most of that code does, but what I need, is what exactly this code does: Code: [Select] preg_match("#[a-z0-9]([-a-z0-9]+)?(\.[a-z]{2,3})?(\.[a-z]{2,4})#i", $pagetext)Can anyone break this down and tell me what exactly does what? Thanks in advance I'm creating a social network for a friend and I need to make a flash webcam to talk to another flash webcam. I have all the flash code working, now all I need is a way to let users match themselves up to each other without other users being able to barge in. What areas of php do I need to learn about to do this? Dallas. Hello, I am writing a CMS for a sports organization league. One of my pages grabs values from the database using only the current week. What I want to do is when the admin enters in a game date, I want it to automatically find the week number for the date they entered. I haven't been able to find anything online that works for me. Any help would be great! Thanks Hello I would like to know how to print data generated by PHP into a bond paper? is there a php function that i can use? hello i have a label printer that i am trying to print to. it prints, but because of ie7 margins, it isnt printing properly. if i go in and manually change the margins, it will print propper. i cannot save the margins small enough though, any thoughts? thanks I'm decoding some strings that were encoded by someone else, I have the key and already made a decoder in C++ and it is working but I want to avoid call "exec". For now I've tried to use mcrypt_decrypt (mcrypt Version 2.5.8) with all possible options but none gives correct results, compared to the correct c++ .exe results. I tried to "convert" the function to PHP around 6 times but none worked, I'm sure there is something I'm missing or I don't know about. This is the working decoder function in c++: Code: [Select] void XTEADecode(LPCVOID lpBuffer, int dwSize, DWORD *lpXteaKey) { LPDWORD lpPtr = (LPDWORD)lpBuffer; int j; for(j=0; j<dwSize; j=j+8){ unsigned long v0=*lpPtr, v1=*(lpPtr+1), i; unsigned long delta=0x9E3779B9, sum=delta*32; for(i=0; i<32; i++) { v1 -= ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + lpXteaKey[sum>>11 & 3]); sum -= delta; v0 -= ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + lpXteaKey[sum & 3]); } *lpPtr=v0; *(lpPtr+1)=v1; lpPtr+=2; } } Any suggestions would be appreciated. Alright, so I have 100 user ids which I need sorted in a very specific way. Right now, they're organized in a 1-100 format. Let's think of each ID as ID#1, ID#2, ID#3 etc all the way up to ID#100. I need to code a script to echo them out in the following order: $ID2.'<br/>'; $ID1.'<br/>'; $ID4.'<br/>'; $ID3.'<br/>'; $ID6.'<br/>'; $ID5.'<br/>'; //etc up to $ID100.'<br/>'; $ID99.'<br/>'; Is there any special algorithm or trick with an array to do this? I will attach a file with each ID seperated by a semi-colon. And also here is the script I have right now which echo's them out in order: <?PHP $File = "IDs.txt"; $Login = file($File); $String = file_get_contents($File); $Logins = explode(";", $String); foreach($Logins as $Login) { echo $Login.'<br/>'; } ?> Hey all. I am racking my brain trying to figure out the best way to handle a certain process my company needs me to do. First I will give a general description of the issue, then I will get into specifics. Basically I have a file that contains a bunch of data. The data stored in the file is consistant, each entry has X number of elements with a total character size of Y. Element 1 in each entry will always take up the same amount of characters. So if I have 2 elements in each data entry, each 5 characters long, then each data entry is 10 characters. Whcih means to access the 2nd element of the 3rd entry I would grab characters 15-20. I would want to be able to search this data for a number of things. Basically id want to be able to say, "give me all results where element 1 = 'pancakes'. Or where element 2 >8. Or more substaintial searches such as element 1>10 AND element 2<5. Is there a good way to do this? My first line of thought would be to run through the file, grabbing every element that can be searched on. So lets say if elements 2 and 4 can be searched on, and I have 10 entries, I would run through and grab an array holding the values for entry 2 and 4. array( array('index=>0', 'element2'=>10, 'element4'=>12), array('index=>1', 'element2'=>11, 'element4'=>-2), array('index=>2', 'element2'=>0, 'element4'=>7) ) Then, depending on the search, I would reorder the array and search through it. So if I wanted to see if element2 was greater then 8, id reorder by element2 and then search. As if this wasnt difficult enough, the issue would be on complex searches such as 'element1>10 OR (element2=6 AND element3=0)' I suppose i could store the result array of each individual search result and then merge/union/intersect based on the AND/OR. To make things ever CRAZIER, the flat files can have other flat files as children. So if I have element1 in file 1 and element1 in file 2, all of file2 data would be part of the corrisponding data in file1. So, id basically need to be able to "join" files. I have thought of a number of solutions, but im not sure how they will pan out. Ugh. In case your wondering WHY I need to do this. My company runs a lot of data off an old database called filepro which uses flat files with index and map files. Right now we have a few systems which weve "synched" with mysql which runs batch updates between the two databases to keep data consistant. We wont be coming "off" of filepro for a long, long time. But a lot of my php/mysql apps need access to the data on filepro. So, Im trying to find a way to quickly be able to search and pull data from filepro into php. Basically, i want to run search queries on the flat files. Basically id like your input on a number of things: Is this even a reasonable attempt? Is the idea of pulling the searched elements into php to actually run the search, then collecting the correct rows and getting the data directly from them a smart move? Once I have the searchable elements and index, what algorithms are good for actually running the search? I am trying to find a tutorial on how to perform a depth first search. I've seen pseudocodes and sources in other languages, but I just can't implement it in PHP no matter what I try. Can anyone show me how or where I can read up on it or how to do it? Hi, I need to create a secure API at work so that 2 systems can interact with each other and request data (json format). I need to use an API key for this but don't want to use an API key stored in a database, what is the best way to go about this? I would like to use some sort of encryption algorithm and a white list of a few values to validate against once decrypted, is this safe and are there any algorithms I can use to generate my keys and white list? I am trying to write a PHP script that implements the MD5 algorithm just so that I can better understand MD5's inner-workings. For those of you already familiar with how MD5 works, could you help me figure out why my script is not producing the correct output? <?php $string = ""; $a = "01100111010001010010001100000001"; // 0x67452301 $b = "11101111110011011010101110001001"; // 0xEFCDAB89 $c = "10011000101110101101110011111110"; // 0x98BADCFE $d = "00010000001100100101010001110110"; // 0x10325476 $aa = $a; $bb = $b; $cc = $c; $dd = $d; // PADDED BINARY FOR NULL STRING, I.E.: "" $binary_md5 = "10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"; $binary_md5_words = strlen($binary_md5) / 32; // SPLIT BINARY INTO 16 32-BIT WORDS for($i = 1; $i <= $binary_md5_words; $i++) { $m[] = substr($binary_md5, ($i - 1) * 32, 32); } // GENERATE T-VALUES for($i = 0; $i < 64; $i++) { $T[] = Pad(decbin(floor(4294967296 * abs(sin($i+1)))), 32); } /* // PRINT THE M[K] ARRAY echo "<h1>m[k] Array</h1><br>"; print_r($m); echo "<br><br>"; // PRINT THE T[t] ARRAY echo "<h1>T[t] Array</h1><br>"; print_r($T); echo "<br><br>"; // TEST ANDxy echo "<h1>Test ANDxy</h1><br>"; echo "$m[0]<br>$T[0]<br>"; echo ANDxy($m[0], $T[0]); echo "<br><br>"; // TEST ORxy echo "<h1>Test ORxy</h1><br>"; echo "$m[0]<br>$T[0]<br>"; echo ORxy($m[0], $T[0]); echo "<br><br>"; // TEST ADDxy echo "<h1>Test ADDxy</h1><br>"; echo "$m[0]<br>$T[0]<br>"; echo ADDxy($m[0], $T[0]); echo "<br><br>"; // TEST XORxy echo "<h1>Test XORxy</h1><br>"; echo "$m[0]<br>$T[0]<br>"; echo XORxy($m[0], $T[0]); echo "<br><br>"; // TEST NOTx echo "<h1>Test NOTx</h1><br>"; echo "$m[0]<br>"; echo NOTx($m[0]); echo "<br><br>"; // TEST SHIFTleft echo "<h1>Test SHIFTleft</h1><br>"; echo "$m[0]<br>"; echo SHIFTleft($m[0], 1); echo "<br><br>"; // TEST F echo "<h1>Test F</h1><br>"; echo "X = $m[0]<br>Y = $m[1]<br>Z = $m[2]<br>F = "; echo F($m[0], $m[1], $m[2]); $step1 = ANDxy($m[0], $m[1]); $step2 = ANDxy(NOTx($m[0]), $m[2]); $step3 = ORxy($step1, $step2); echo "<br>F = $step3"; echo "<br><br>"; // TEST H echo "<h1>Test H</h1><br>"; echo "X = $m[0]<br>Y = $m[1]<br>Z = $m[2]<br>F = "; echo H($m[0], $m[1], $m[2]); echo "<br><br>"; */ // ROUND 1 $a = ff($a, $b, $c, $d, $m, 0, 7, $T[0]); $d = ff($d, $a, $b, $c, $m, 1, 12, $T[1]); $c = ff($c, $d, $a, $b, $m, 2, 17, $T[2]); $b = ff($b, $c, $d, $a, $m, 3, 22, $T[3]); $a = ff($a, $b, $c, $d, $m, 4, 7, $T[4]); $d = ff($d, $a, $b, $c, $m, 5, 12, $T[5]); $c = ff($c, $d, $a, $b, $m, 6, 17, $T[6]); $b = ff($b, $c, $d, $a, $m, 7, 22, $T[7]); $a = ff($a, $b, $c, $d, $m, 8, 7, $T[8]); $d = ff($d, $a, $b, $c, $m, 9, 12, $T[9]); $c = ff($c, $d, $a, $b, $m, 10, 17, $T[10]); $b = ff($b, $c, $d, $a, $m, 11, 22, $T[11]); $a = ff($a, $b, $c, $d, $m, 12, 17, $T[12]); $d = ff($d, $a, $b, $c, $m, 13, 12, $T[13]); $c = ff($c, $d, $a, $b, $m, 14, 17, $T[14]); $b = ff($b, $c, $d, $a, $m, 15, 22, $T[15]); // ROUND 2 $a = gg($a, $b, $c, $d, $m, 1, 5, $T[16]); $d = gg($d, $a, $b, $c, $m, 6, 9, $T[17]); $c = gg($c, $d, $a, $b, $m, 11, 14, $T[18]); $b = gg($b, $c, $d, $a, $m, 0, 20, $T[19]); $a = gg($a, $b, $c, $d, $m, 5, 5, $T[20]); $d = gg($d, $a, $b, $c, $m, 10, 9, $T[21]); $c = gg($c, $d, $a, $b, $m, 15, 14, $T[22]); $b = gg($b, $c, $d, $a, $m, 4, 20, $T[23]); $a = gg($a, $b, $c, $d, $m, 9, 5, $T[24]); $d = gg($d, $a, $b, $c, $m, 14, 9, $T[25]); $c = gg($c, $d, $a, $b, $m, 3, 14, $T[26]); $b = gg($b, $c, $d, $a, $m, 8, 20, $T[27]); $a = gg($a, $b, $c, $d, $m, 13, 5, $T[28]); $d = gg($d, $a, $b, $c, $m, 2, 9, $T[29]); $c = gg($c, $d, $a, $b, $m, 7, 14, $T[30]); $b = gg($b, $c, $d, $a, $m, 12, 20, $T[31]); // ROUND 3 $a = hh($a, $b, $c, $d, $m, 5, 4, $T[32]); $d = hh($d, $a, $b, $c, $m, 8, 11, $T[33]); $c = hh($c, $d, $a, $b, $m, 11, 16, $T[34]); $b = hh($b, $c, $d, $a, $m, 14, 23, $T[35]); $a = hh($a, $b, $c, $d, $m, 1, 4, $T[36]); $d = hh($d, $a, $b, $c, $m, 4, 11, $T[37]); $c = hh($c, $d, $a, $b, $m, 7, 16, $T[38]); $b = hh($b, $c, $d, $a, $m, 10, 23, $T[39]); $a = hh($a, $b, $c, $d, $m, 13, 4, $T[40]); $d = hh($d, $a, $b, $c, $m, 0, 11, $T[41]); $c = hh($c, $d, $a, $b, $m, 3, 16, $T[42]); $b = hh($b, $c, $d, $a, $m, 6, 23, $T[43]); $a = hh($a, $b, $c, $d, $m, 9, 4, $T[44]); $d = hh($d, $a, $b, $c, $m, 12, 11, $T[45]); $c = hh($c, $d, $a, $b, $m, 15, 16, $T[46]); $b = hh($b, $c, $d, $a, $m, 2, 23, $T[47]); // ROUND 4 $a = ii($a, $b, $c, $d, $m, 0, 6, $T[48]); $d = ii($d, $a, $b, $c, $m, 7, 10, $T[49]); $c = ii($c, $d, $a, $b, $m, 14, 15, $T[50]); $b = ii($b, $c, $d, $a, $m, 5, 21, $T[51]); $a = ii($a, $b, $c, $d, $m, 12, 6, $T[52]); $d = ii($d, $a, $b, $c, $m, 3, 10, $T[53]); $c = ii($c, $d, $a, $b, $m, 10, 15, $T[54]); $b = ii($b, $c, $d, $a, $m, 1, 21, $T[55]); $a = ii($a, $b, $c, $d, $m, 8, 6, $T[56]); $d = ii($d, $a, $b, $c, $m, 15, 10, $T[57]); $c = ii($c, $d, $a, $b, $m, 6, 15, $T[58]); $b = ii($b, $c, $d, $a, $m, 13, 21, $T[59]); $a = ii($a, $b, $c, $d, $m, 4, 6, $T[60]); $d = ii($d, $a, $b, $c, $m, 11, 10, $T[61]); $c = ii($c, $d, $a, $b, $m, 2, 15, $T[62]); $b = ii($b, $c, $d, $a, $m, 9, 21, $T[63]); $a = ADDxy($a, $aa); $b = ADDxy($b, $bb); $c = ADDxy($c, $cc); $d = ADDxy($d, $dd); // ECHO RESULTS echo "<h1>String</h1><br>"; echo "String: '$string'<br>"; $md5 = md5($string); echo "MD5: $md5<br><br>"; $md5_1 = substr($md5, 0, 8); $md5_2 = substr($md5, 8, 8); $md5_3 = substr($md5, 16, 8); $md5_4 = substr($md5, 24, 8); echo "A = $md5_1<br>B = $md5_2<br>C = $md5_3<br>D = $md5_4<br><br>"; $md5_bin_a = Pad(decbin(hexdec($md5_1)), 32); $md5_bin_b = Pad(decbin(hexdec($md5_2)), 32); $md5_bin_c = Pad(decbin(hexdec($md5_3)), 32); $md5_bin_d = Pad(decbin(hexdec($md5_4)), 32); echo "A = $md5_bin_a<br>B = $md5_bin_b<br>C = $md5_bin_c<br>D = $md5_bin_d<br><br>"; echo "<h1>Results</h1><br>"; echo "A = $a<br>B = $b<br>C = $c<br>D = $d<br><br>"; $a_dec = bindec($a); $b_dec = bindec($b); $c_dec = bindec($c); $d_dec = bindec($d); $a_hex = dechex($a_dec); $b_hex = dechex($b_dec); $c_hex = dechex($c_dec); $d_hex = dechex($d_dec); echo "A = $a_hex<br>B = $b_hex<br>C = $c_hex<br>D = $d_hex<br><br>"; // FUNCTIONS function ff($a, $b, $c, $d, $m, $k, $s, $t) { //a = b + ((a + F(b,c,d) + X[k] + T[i]) <<< s) return ADDxy($b, SHIFTleft(ADDxy(ADDxy(ADDxy($a, F($b, $c, $d)), $m[$k]), $t), $s)); } function gg($a, $b, $c, $d, $m, $k, $s, $t) { //a = b + ((a + G(b,c,d) + X[k] + T[i]) <<< s) return ADDxy($b, SHIFTleft(ADDxy(ADDxy(ADDxy($a, G($b, $c, $d)), $m[$k]), $t), $s)); } function hh($a, $b, $c, $d, $m, $k, $s, $t) { //a = b + ((a + H(b,c,d) + X[k] + T[i]) <<< s) return ADDxy($b, SHIFTleft(ADDxy(ADDxy(ADDxy($a, H($b, $c, $d)), $m[$k]), $t), $s)); } function ii($a, $b, $c, $d, $m, $k, $s, $t) { //a = b + ((a + I(b,c,d) + X[k] + T[i]) <<< s) return ADDxy($b, SHIFTleft(ADDxy(ADDxy(ADDxy($a, I($b, $c, $d)), $m[$k]), $t), $s)); } function F($X, $Y, $Z) { //return ($X & $Y) | ((~$X) & $Z); return ORxy(ANDxy($X, $Y), ANDxy(NOTx($X), $Z)); } function G($X, $Y, $Z) { //return ($X & $Z) | ($Y & (~$Z)); return ORxy(ANDxy($X, $Z), ANDxy($Y, NOTx($Z))); } function H($X, $Y, $Z) { //return $X ^ $Y ^ $Z; return XORxy(XORxy($X, $Y), $Z); } function I($X, $Y, $Z) { //return $Y ^ ($X | (~$Z)); return XORxy($Y, ORxy($X, NOTx($Z))); } function Pad($binary, $pad_length) { $pad_length = $pad_length - strlen($binary); for($i = 0; $i < $pad_length; $i++) { $padding .= '0'; } return $padding . $binary; } function mod($val, $div) { $r = $val - (floor($val/$div)*$div); return $r; } function ANDxy($x, $y) { $x_dec = bindec($x); $y_dec = bindec($y); $result = $x_dec & $y_dec; $result = Pad(decbin($result), strlen($x)); return $result; } function ORxy($x, $y) { $x_dec = bindec($x); $y_dec = bindec($y); $result = $x_dec | $y_dec; $result = Pad(decbin($result), strlen($x)); return $result; } function ADDxy($x, $y) { $x_dec = bindec($x); $y_dec = bindec($y); $result = mod($x_dec + $y_dec, pow(2, 32)); $result = Pad(decbin($result), strlen($x)); return $result; } function XORxy($x, $y) { $x_dec = bindec($x); $y_dec = bindec($y); $result = $x_dec ^ $y_dec; $result = Pad(decbin($result), strlen($x)); return $result; } function NOTx($x) { $x_dec = bindec($x); $result = ~$x_dec; $result = Pad(decbin($result), strlen($x)); return $result; } function SHIFTleft($x, $y) { $x_dec = bindec($x); $result = $x_dec << $y; $result = Pad(decbin($result), strlen($x)); return $result; } function SHIFTright($x, $y) { $x_dec = bindec($x); $result = $x_dec >> $y; $result = Pad(decbin($result), strlen($x)); return $result; } ?> I use mysql to retrieve data from database and use php to display the data onto website directly by the following codes : $query2 = "SELECT message FROM messages WHERE username='{$username1}'"; $result2 = mysql_query($query2,$connection) or die (mysql_error()); confirm_query($result2); while($userinfo = mysql_fetch_array($result2)){ echo "<div class=\"messagepiece\">" . $userinfo['message'] . "</div><br>"; } I want the div(s) arrange style like on the picture http://2aek.com/inventory/divs.jpg display the 1st 4 divs onto 1st column, jump to 2nd column to display another 4 divs.... Below are the codes of how the divs arrangement : <div class="test1" style="left:0px; top:0px;"> asdawdaw </div> <div class="test1" style="left:0px; top:70px;"> asdawdaw </div> <div class="test1" style="left:0px; top:140px;"> asdawdaw </div> <div class="test1" style="left:0px; top:210px;"> asdawdaw </div> <div class="test1" style="left:200px; top:35px;"> asdawdaw </div> <div class="test1" style="left:200px; top:105px;"> asdawdaw </div> <div class="test1" style="left:200px; top:175px;"> asdawdaw </div> <div class="test1" style="left:200px; top:245px;"> asdawdaw </div> <div class="test1" style="left:400px; top:0px;"> asdawdaw </div> <div class="test1" style="left:400px; top:70px;"> asdawdaw </div> <div class="test1" style="left:400px; top:140px;"> asdawdaw </div> <div class="test1" style="left:400px; top:210px;"> asdawdaw </div> So the looping styles should be something like : loop left 0 for four times > 200 for four times > 400 for four times. loop top 0 > 70 > 140 > 210 then 35 > 105 > 175 > 245 then again 0 > 70 > 140 > 210. Seriously I don't know how to write the algorithm of looping. I guess the looping algorithm for left should be something like : i = 0 ; i=>4 ; i++{ k=0; k=>20000; k+200{} } But it is so wrong, it will stop at 4th loop and each loop will be 0, 200, 400, 800. That's not what I want. Seriously I can't figure out the algorithm, my brain is stupid, so can you guys guide me please? Hello, is it possible to created a variable for a pseudo class?
For example I normally do something like this.
$tableWrapper = "background-color:{$alertColor};font-size:12px; padding: 0px 5px 5px 5px;text-align:center;";Then when I use it in my HTML I would call the variable like so. $tData .= "<div style='{$tableWrapper}'>\n";But for something like this $ul.alertLegend liWouldn't work because of the period. Is this possible to do? I really need to be able to do this since the color that will be included in the class is being pulled from an array depending on a certain value. So is it possible to created a variable for for pseudo class? -Thanks
I made a post a while back about this topic he 1. The input from the project will be coming from a mobile app which will be using a qr code. The qr code contains the Room Number and the 2 Access Points for each room. When a user scans the qr code it will pass that info to the web app that has the algorithm and verify what room he/she is in the access point that was 'scanned'. 2. For the testing of the project we decided to use two rooms of the building of our alma mater and the access points were already defined based on tests:
Room 413 has Access Point 1 that have the values of -67 dBm to -89 dBm and Access Point 2 that have the values of -40 dbm to -57 dBm while
3. I already inputted the values and the rooms I've mentioned above in mysql to verify if the input from the qr code that was scanned it correct. but sadly we are stuck with the algorithm itself.
Hello, I'm building a blog post website, and now I'm on the search part of it. I have a search field which I instruct the user to type in "keywords" they want to search for. The words they type in there are then to be searched in the "title" and "content" of each post in the "posts" table. Here's an example query of my current setup: SELECT * FROM (`posts`) WHERE MATCH(title,content) AGAINST('+term1* ' IN BOOLEAN MODE); This works fine if I have one or two words in they keywords. If I, however, copy and paste an entire sentence from an existing blog post, no results are found ??? Here's an example of a query where I just copy+pasted a sentence from a blog post: SELECT * FROM (`posts`) WHERE MATCH(title,content) AGAINST('+Hello* +everyone* +my* +name* +is* +Bob* ' IN BOOLEAN MODE); Yet, a search for just "Bob" returns the proper result. WHY? What's a better way to perform this search?! Hallo everybody!
I am looking for some information about creating PHP threaded forum (with MySQL). BB forum is easy - db table with forums, topics and posts, every post has foreign key to topic, topic to forum and it's done. But if I want something like Disqus, how to do this more efficiently? How to collect posts in db with minimum query needed to render any thread?
And what about post rating? How to prevent user from sending more then one rating?
Hello Guys,
You might have known about Luhn Algorithm, which is used to get checksum of IMEI of phones, credit cards etc etc. It is a public domain so it is not used for security but to ensure that client has passed the correct numbers etc etc.
Anyway, I am trying to get my hands on this algorithm and I will build a logic based on luhn algo to get the checksum, where I am stuck is how can I get the alternate numbers from a numeric string, for example I have written the following code to get all the numbers one by one into the array.
$imei = "356565451265856"; $lenOfStr= strlen($imei); $myArray = array(); //Get all numbers one by one in array for($i=0; $i < $lenOfStr; $i++){ $myArray[] = substr($imei,$i,1); } // Checking the array foreach($myArray as $seperatedNumbers){ echo $seperatedNumbers; }No the problem is that I want to select every 2nd number from right to left e-g 5,5,2,... or 6,8,6 How can I get it done? This logic may not be so good, there may be more brilliant solutions to write luhn algo, but I want to try myself once... Thanks. Edited by Digitizer, 31 August 2014 - 04:53 PM. What is the difference between the hash algo "tiger192,3" and "tiger192,4"? I ran fsum/HashCalc to get a TIGER hash from a string and it is different with either "tiger192,3" or "tiger192,4". I also tried using the hash as hex string input to rehash 3 or 4 times, but still cannot get an equivalent to that of "tiger192,3" or "tiger192,4"... This topic has been moved to Third Party PHP Scripts. http://www.phpfreaks.com/forums/index.php?topic=354524.0 |