Jump to content

Search the Community

Showing results for tags 'algorithm'.

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


Forums

  • Welcome to PHP Freaks
    • Announcements
    • Introductions
  • PHP Coding
    • PHP Coding Help
    • Regex Help
    • Third Party Scripts
    • FAQ/Code Snippet Repository
  • SQL / Database
    • MySQL Help
    • PostgreSQL
    • Microsoft SQL - MSSQL
    • Other RDBMS and SQL dialects
  • Client Side
    • HTML Help
    • CSS Help
    • Javascript Help
    • Other
  • Applications and Frameworks
    • Applications
    • Frameworks
    • Other Libraries
  • Web Server Administration
    • PHP Installation and Configuration
    • Linux
    • Apache HTTP Server
    • Microsoft IIS
    • Other Web Server Software
  • Other
    • Application Design
    • Other Programming Languages
    • Editor Help (PhpStorm, VS Code, etc)
    • Website Critique
    • Beta Test Your Stuff!
  • Freelance, Contracts, Employment, etc.
    • Services Offered
    • Job Offerings
  • General Discussion
    • PHPFreaks.com Website Feedback
    • Miscellaneous

Find results in...

Find results that contain...


Date Created

  • Start

    End


Last Updated

  • Start

    End


Filter by number of...

Joined

  • Start

    End


Group


AIM


MSN


Website URL


ICQ


Yahoo


Jabber


Skype


Location


Interests


Age


Donation Link

Found 9 results

  1. I made a post a while back about this topic here: and I've clarified a few things with my friend. 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 Room 415 has Access Point 1 that have the values of -30 dBm to -46 dBm and Access Point 2 that have the values of -75 dBm to -100 dBm 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.
  2. Hello, Have an associative array of variable length and variable key names. The POST array can have the following structure, where [rec_n] can have one or many elements. : $_POST Array ( [rec_1769057] => on [rec_1768743] => on [ponumb] => D000000034 [strnbr] => 100 ) The 'n' is a variable SKU number and concatenated from a select statement. There are thousands of SKUs. PONUMB and STRNBR are static and will always be at the end of the array. I have an algorithm for slicing this array into two separate arrays. skuitems Array ( [rec_1769057] => on [rec_1768743] => on ) postrnbr Array ( [ponumb] => D000000034 [strnbr] => 100 ) The two arrays are then assigned to a $params array one for each update statement... $params Array ( [0] => Array ( [0] => 1768743 [1] => D000000034 [2] => 100 ) [1] => Array ( [0] => 1769057 [1] => D000000034 [2] => 100 )) I would like to accomplish the above in one go... At present the solution has and O(2) notation. Here is the algorithm that works, but seems clunky to me. if( isset($postar) && is_array($postar)) { // first order of mag. $cnt = count($postar) - 2; // total minus last two elements $postrnbr = array_slice( $postar, -2, 2 ); // always ponumb and strnbr $skuitems = array_slice($postar, 0, $cnt); // will be one or more sku items $skukeys = array_keys($skuitems); $qparams = array(); //bind params for update statement foreach($skukeys as $sku) { // second order of mag. $skusplit = explode("_",$sku); // ie Array( [0]=>rec, [1]=>1234545 ) $qparams[] = array($skusplit[1], $postrnbr['ponumb'], $postrnbr['strnbr']); } } Thanks in advance! rwhite35
  3. Hi guys, I'm trying to calculate where a future date runs in a 15 day cycle pattern, and then if the day lands on day 13 or 15 of the cycle pattern I want to do something with the result. For example: $pattern = 15; $start_date = strtotime("2015-12-14"); // day 1 // Day 15 = 2015-12-29 $chosen_date = strtotime("2016-03-30"); $difference = ($chosen_date - $start_date) / 83400; // Find which Day the 'chosen_date' comes in the sequence and... If($chosen_date == 13 || $chosen_date == 15) { Echo 'possible outcome. Day $chosen_date."; } Else { Echo 'not possible, day $chosen_date'; } Hope it makes sense! Cheers
  4. Hello everybody! I am trying to figure out how to obtain all the data related to a key, but I've got no results so far and I am becoming really frustated, let's see if any of you could help me out with this. Imagine I have a table with several columns, but we bother about two of them, let's say we have serial numbers of some product, on the left Incoming serial number (we can repair or swap the unit), on the right the outcoming serial number (same if we have repared the unit, different if we swap it for another unit). Then we have, for example: A -> A (Unit A enters and we repaired it) A -> B (Same unit came another day for some reason and we couldn't repair it, so we swap it by giving B to the customer) B -> C (Unluckily B was defective so we have to change it again) C -> C (C had another problem and we repaired it) We have that in the database from different days and the such, so now, we want to know the historical and we know "C". If we perform a SELECT * FROM... WHERE incoming/outcoming serial number = "C" we'll get: B -> C C -> C So we should seek now for B and keep going... but I cannot proceed correctly, 'cause if I SELECT using B I'll get again B -> C (and A -> B, what I want), but when do I know I have to finish? How could I implement this as a function or whatever? showing every not repeated line from the beginning. Could your minds help mine? Thank you very much in advance!.
  5. Hi All, I am a new PHP Developer. I would like to ask you on PHP problem with algorithm. Please see the attach file for programming problem. Thanks, Man
  6. Hi everyone, i have some troubles to solve this "grouping" problem. I have 2D (nxn) array and i want to group all related item to groups. Items are considered to be related in 2 cases: when they have the same edge or top. $table = array( array( 0, 0, 0, 0, 0, 0), array( 0, 0, 1, 2, 0, 0), array( 0, 0, 0, 0, 0, 0), array( 0, 3, 0, 4, 0, 0), array( 0, 0, 5, 0, 0, 0), array( 0, 0, 0, 6, 0, 7) ); And this is result which i want to achieve : $groups= array( array( 1, 2), array( 3, 4, 5, 6), array( 7 ), ); I will be grateful for any help. THX
  7. all, I have this block of code: If ($ctr = 4) { for ($block = 1; $block <= 9; $block++) { for ($ctr2 = 1; $ctr2 <= 3; $ctr2++) { //each line. for ($ctr3 = 1; $ctr3 <= 3; $ctr3++) { //char 1 - 3 in each line. switch ($ctr2) { //which line? Case 1: $strOut = $strOut . substr($Line1, $ctr3, 1); Case 2: $strOut = $strOut . substr($Line2, $ctr3, 1); Case 3: $strOut = $strOut . substr($Line3, $ctr3, 1); } } } } } what I'd like to do is streamline it. There are 3 lines of text being captured here. What is (supposed to be) happening is that each block of characters (3 characters per line positions, starting at position 1 or positions every 3 char increments after that) is being captured until all 9 chars are stored in $strOut. 9 chars = 3 chars on each line * 3 lines. is there any better way to do this mathematically? I realize that we can manipulate the variables and coding many different ways, but I'm not interested in that. I'm only interested in using math or leveraging techniques to speed up the process here. Resources from PHP would be OK but I'm trying to focus on the massive iteration and turning it into something more useful. comments welcome. thanks!
  8. Well, I am a total Python Newbie but know PHP very well, I wanted to create a website that would help people to generate Word crosswords, hence after a little web search I found this Python Code which I need help in converting to PHP> I tried myself but failed as I know nothing about Python, I also tried an online conversion tool, but without any luck, so if anyone here can help me convert the following code to PHP, it will be highly respected. Heres the code: import random, re, time, string from copy import copy as duplicate class Crossword(object): def __init__(self, cols, rows, empty = '-', maxloops = 2000, available_words=[]): self.cols = cols self.rows = rows self.empty = empty self.maxloops = maxloops self.available_words = available_words self.randomize_word_list() self.current_word_list = [] self.debug = 0 self.clear_grid() def clear_grid(self): # initialize grid and fill with empty character self.grid = [] for i in range(self.rows): ea_row = [] for j in range(self.cols): ea_row.append(self.empty) self.grid.append(ea_row) def randomize_word_list(self): # also resets words and sorts by length temp_list = [] for word in self.available_words: if isinstance(word, Word): temp_list.append(Word(word.word, word.clue)) else: temp_list.append(Word(word[0], word[1])) random.shuffle(temp_list) # randomize word list temp_list.sort(key=lambda i: len(i.word), reverse=True) # sort by length self.available_words = temp_list def compute_crossword(self, time_permitted = 1.00, spins=2): time_permitted = float(time_permitted) count = 0 copy = Crossword(self.cols, self.rows, self.empty, self.maxloops, self.available_words) start_full = float(time.time()) while (float(time.time()) - start_full) < time_permitted or count == 0: # only run for x seconds self.debug += 1 copy.current_word_list = [] copy.clear_grid() copy.randomize_word_list() x = 0 while x < spins: # spins; 2 seems to be plenty for word in copy.available_words: if word not in copy.current_word_list: copy.fit_and_add(word) x += 1 #print copy.solution() #print len(copy.current_word_list), len(self.current_word_list), self.debug # buffer the best crossword by comparing placed words if len(copy.current_word_list) > len(self.current_word_list): self.current_word_list = copy.current_word_list self.grid = copy.grid count += 1 return def suggest_coord(self, word): count = 0 coordlist = [] glc = -1 for given_letter in word.word: # cycle through letters in word glc += 1 rowc = 0 for row in self.grid: # cycle through rows rowc += 1 colc = 0 for cell in row: # cycle through letters in rows colc += 1 if given_letter == cell: # check match letter in word to letters in row try: # suggest vertical placement if rowc - glc > 0: # make sure we're not suggesting a starting point off the grid if ((rowc - glc) + word.length) <= self.rows: # make sure word doesn't go off of grid coordlist.append([colc, rowc - glc, 1, colc + (rowc - glc), 0]) except: pass try: # suggest horizontal placement if colc - glc > 0: # make sure we're not suggesting a starting point off the grid if ((colc - glc) + word.length) <= self.cols: # make sure word doesn't go off of grid coordlist.append([colc - glc, rowc, 0, rowc + (colc - glc), 0]) except: pass # example: coordlist[0] = [col, row, vertical, col + row, score] #print word.word #print coordlist new_coordlist = self.sort_coordlist(coordlist, word) #print new_coordlist return new_coordlist def sort_coordlist(self, coordlist, word): # give each coordinate a score, then sort new_coordlist = [] for coord in coordlist: col, row, vertical = coord[0], coord[1], coord[2] coord[4] = self.check_fit_score(col, row, vertical, word) # checking scores if coord[4]: # 0 scores are filtered new_coordlist.append(coord) random.shuffle(new_coordlist) # randomize coord list; why not? new_coordlist.sort(key=lambda i: i[4], reverse=True) # put the best scores first return new_coordlist def fit_and_add(self, word): # doesn't really check fit except for the first word; otherwise just adds if score is good fit = False count = 0 coordlist = self.suggest_coord(word) while not fit and count < self.maxloops: if len(self.current_word_list) == 0: # this is the first word: the seed # top left seed of longest word yields best results (maybe override) vertical, col, row = random.randrange(0, 2), 1, 1 ''' # optional center seed method, slower and less keyword placement if vertical: col = int(round((self.cols + 1)/2, 0)) row = int(round((self.rows + 1)/2, 0)) - int(round((word.length + 1)/2, 0)) else: col = int(round((self.cols + 1)/2, 0)) - int(round((word.length + 1)/2, 0)) row = int(round((self.rows + 1)/2, 0)) # completely random seed method col = random.randrange(1, self.cols + 1) row = random.randrange(1, self.rows + 1) ''' if self.check_fit_score(col, row, vertical, word): fit = True self.set_word(col, row, vertical, word, force=True) else: # a subsquent words have scores calculated try: col, row, vertical = coordlist[count][0], coordlist[count][1], coordlist[count][2] except IndexError: return # no more cordinates, stop trying to fit if coordlist[count][4]: # already filtered these out, but double check fit = True self.set_word(col, row, vertical, word, force=True) count += 1 return def check_fit_score(self, col, row, vertical, word): ''' And return score (0 signifies no fit). 1 means a fit, 2+ means a cross. The more crosses the better. ''' if col < 1 or row < 1: return 0 count, score = 1, 1 # give score a standard value of 1, will override with 0 if collisions detected for letter in word.word: try: active_cell = self.get_cell(col, row) except IndexError: return 0 if active_cell == self.empty or active_cell == letter: pass else: return 0 if active_cell == letter: score += 1 if vertical: # check surroundings if active_cell != letter: # don't check surroundings if cross point if not self.check_if_cell_clear(col+1, row): # check right cell return 0 if not self.check_if_cell_clear(col-1, row): # check left cell return 0 if count == 1: # check top cell only on first letter if not self.check_if_cell_clear(col, row-1): return 0 if count == len(word.word): # check bottom cell only on last letter if not self.check_if_cell_clear(col, row+1): return 0 else: # else horizontal # check surroundings if active_cell != letter: # don't check surroundings if cross point if not self.check_if_cell_clear(col, row-1): # check top cell return 0 if not self.check_if_cell_clear(col, row+1): # check bottom cell return 0 if count == 1: # check left cell only on first letter if not self.check_if_cell_clear(col-1, row): return 0 if count == len(word.word): # check right cell only on last letter if not self.check_if_cell_clear(col+1, row): return 0 if vertical: # progress to next letter and position row += 1 else: # else horizontal col += 1 count += 1 return score def set_word(self, col, row, vertical, word, force=False): # also adds word to word list if force: word.col = col word.row = row word.vertical = vertical self.current_word_list.append(word) for letter in word.word: self.set_cell(col, row, letter) if vertical: row += 1 else: col += 1 return def set_cell(self, col, row, value): self.grid[row-1][col-1] = value def get_cell(self, col, row): return self.grid[row-1][col-1] def check_if_cell_clear(self, col, row): try: cell = self.get_cell(col, row) if cell == self.empty: return True except IndexError: pass return False def solution(self): # return solution grid outStr = "" for r in range(self.rows): for c in self.grid[r]: outStr += '%s ' % c outStr += '\n' return outStr def word_find(self): # return solution grid outStr = "" for r in range(self.rows): for c in self.grid[r]: if c == self.empty: outStr += '%s ' % string.lowercase[random.randint(0,len(string.lowercase)-1)] else: outStr += '%s ' % c outStr += '\n' return outStr def order_number_words(self): # orders words and applies numbering system to them self.current_word_list.sort(key=lambda i: (i.col + i.row)) count, icount = 1, 1 for word in self.current_word_list: word.number = count if icount < len(self.current_word_list): if word.col == self.current_word_list[icount].col and word.row == self.current_word_list[icount].row: pass else: count += 1 icount += 1 def display(self, order=True): # return (and order/number wordlist) the grid minus the words adding the numbers outStr = "" if order: self.order_number_words() copy = self for word in self.current_word_list: copy.set_cell(word.col, word.row, word.number) for r in range(copy.rows): for c in copy.grid[r]: outStr += '%s ' % c outStr += '\n' outStr = re.sub(r'[a-z]', ' ', outStr) return outStr def word_bank(self): outStr = '' temp_list = duplicate(self.current_word_list) random.shuffle(temp_list) # randomize word list for word in temp_list: outStr += '%s\n' % word.word return outStr def legend(self): # must order first outStr = '' for word in self.current_word_list: outStr += '%d. (%d,%d) %s: %s\n' % (word.number, word.col, word.row, word.down_across(), word.clue ) return outStr class Word(object): def __init__(self, word=None, clue=None): self.word = re.sub(r'\s', '', word.lower()) self.clue = clue self.length = len(self.word) # the below are set when placed on board self.row = None self.col = None self.vertical = None self.number = None def down_across(self): # return down or across if self.vertical: return 'down' else: return 'across' def __repr__(self): return self.word ### end class, start execution #start_full = float(time.time()) word_list = ['saffron', 'The dried, orange yellow plant used to as dye and as a cooking spice.'], \ ['pumpernickel', 'Dark, sour bread made from coarse ground rye.'], \ ['leaven', 'An agent, such as yeast, that cause batter or dough to rise..'], \ ['coda', 'Musical conclusion of a movement or composition.'], \ ['paladin', 'A heroic champion or paragon of chivalry.'], \ ['syncopation', 'Shifting the emphasis of a beat to the normally weak beat.'], \ ['albatross', 'A large bird of the ocean having a hooked beek and long, narrow wings.'], \ ['harp', 'Musical instrument with 46 or more open strings played by plucking.'], \ ['piston', 'A solid cylinder or disk that fits snugly in a larger cylinder and moves under pressure as in an engine.'], \ ['caramel', 'A smooth chery candy made from suger, butter, cream or milk with flavoring.'], \ ['coral', 'A rock-like deposit of organism skeletons that make up reefs.'], \ ['dawn', 'The time of each morning at which daylight begins.'], \ ['pitch', 'A resin derived from the sap of various pine trees.'], \ ['fjord', 'A long, narrow, deep inlet of the sea between steep slopes.'], \ ['lip', 'Either of two fleshy folds surrounding the mouth.'], \ ['lime', 'The egg-shaped citrus fruit having a green coloring and acidic juice.'], \ ['mist', 'A mass of fine water droplets in the air near or in contact with the ground.'], \ ['plague', 'A widespread affliction or calamity.'], \ ['yarn', 'A strand of twisted threads or a long elaborate narrative.'], \ ['snicker', 'A snide, slightly stifled laugh.'] a = Crossword(13, 13, '-', 5000, word_list) a.compute_crossword(2) print a.word_bank() print a.solution() print a.word_find() print a.display() print a.legend() print len(a.current_word_list), 'out of', len(word_list) print a.debug #end_full = float(time.time()) #print end_full - start_full
  9. 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.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.