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+====MARCH 21, 2016====
+==Week 10==
+This week we welcomed our first official project: Monte Carlo Pi. The concept started as an homage to Pi day and blossomed into a project type thing.
+**A Little Background Information**
+The Monte Carlo method is a class of computational algorithms relying on pseudo random samplings to obtain numerical results. The method is useful for obtaining numerical solutions to problems that are too complex to solve otherwise.
+We started with a PHP program that calculated Pi by generating pseudo random numbers, which were then counted by how many landed within the circle and how many landed in the square. We then multiplied by four the number of iterations that fell within the circle and divided that outcome by the number of iterations that fell in the square.
+**The Math Explained**
+Full disclosure I am "appropriating" this explanation from the interwebs because, well…math.
+The area of a circle is equal to:
+  area = Pi * (radius * radius)
+The area of a square is equal to:
+  area = s₂ or length of one side * length of one side
+When you enclose a circle within a square the length of one side of the square is equal to 2 * the radius of the circle.
+The area of the square is equal to:
+  area = (2 * radius) * (2 * radius) = 4 * (radius * radius)
+Dividing the area of the circle by the area of the square yields Pi/4. To get the value of Pi we multiply the area of the circle by four and divide the result by the area of the square surrounding the circle.
+[[http://mytinylab.com/20101020_MonteCarloSimulationToCalculatePiInPHP]]
+**The Code**
+Now for a look at the code that runs all that complicated math.
+We start by declaring and defining our variables.
+The number of iterations it takes to estimate Pi
+  $iterations  = 35000;
+The radius of the circle
+  $radius = 1.00;
+Calculate radius squared
+  $radiusSquare  = $radius * $radius;
+  $count   = 0;
+  $init	   = 0;
+Next up is the for loop.
+  for ($iters = 0;  $iters < $iterations;  $iters++)
+  {
+    $x = lcg_value();     -- random x-coordinate
+    $y = lcg_value();     -- random y-coordinate
+The lcg_value() math function in PHP returns a pseudo random float value in the range of (0,1). For both the x and y coordinates a random number from 0 to radius or 1 because we set the value of radius to 1 is chosen.
+The coordinates inside the square of the radius
+  $isin   = ($x * $x) + ($y * $y);
+  if ($isin  <= $radiusSquare)
+  {
+  Count the number of points in the circle
+    $init = $init + 1;
+   }
+  }
+The number of points inside the square
+  $pi 	= ($init * 4) / $iterations;
+Originally we output the results to the browser in text format.
+  # in the square: 35000
+  # in the circle: 275001
+  pi = 3.1428685714286
+Finding the results visually boring it was decided that we incorporate our results into a visually stimulating graph. Thus a project was crafted. The challenge laid before us was to graphically plot the points of the original text output onto a circle within a square.
+====APRIL 4, 2016====
+==Week 11==
+Coming off break week, I have nothing exciting to report. We buttoned up our Monte Carlo Pi PHP program before break began, which leaves us open to starting something new this week.
+In last week’s OPUS, post I broke down the PHP code used to calculate Monte Carlo Pi and left off with a tantalizing pointer to a project. This week I will break down the code for implementing the Monte Carlo Pi code into a graphical display of goodness involving rectangles, circles, and pixels.
+The first step was to figure out how to visually display the graph in a web browser. I started by wrapping everything in HTML tags and then went on to create the graph (rectangle, nested circle, and plotted points) in PHP. It functioned, output a bordered rectangle with a nested circle, and plotted points. I abandoned this method and moved to what is the “final” version of the project after realizing that all the steps could be accomplished using only PHP.
+**The Code**
+First up is creating the container for the graph.  Leaving an extra 100 pixels on the height allows room to add the string output of the plotted point count at the bottom of the graph.
+  $img = imagecreatetruecolor(800, 900);
+Next step is to mix up our virtual palette of colors. One color example is listed below.
+  $redish = imagecolorallocate($img, 100, 0, 0);
+**Now for the graph**
+Start by creating a rectangle to hold the nested circle and plotted points.
+  imagefilledrectangle($img, 0, 0, 800, 800);
+The allotted x and y coordinates fill the container created above with the exception of 100 pixels at the bottom, which is reserved for output that’ll be explained later.
+To nest a circle in the rectangle you can use either the imagefilledellipse() or imagefilledarc() function. I chose the arc function.
+  imagefilledarc($img, 400, 400, 600, 600, 0, 360, $redish, IMG_ARC_PIE);
+imagefilledarc draws a partial arc centered at a specified coordinate with the image. It takes nine parameters listed below.
+  * $img is the image resource returned by imagecreatetruecolor
+  * The x-coordinate (400) and y-coordinate (400) of the center
+  * The width (600) and height (600) of the arc
+  * The starting (0) and ending angle (360), in degrees of the arc
+  * A color identifier chosen from our virtual palette ($redish)
+  * A style (IMG_ARC_PIE), which produces a rounded edge
+After the creation of the rectangle and nested circle add the Monte Carlo Pi function explained last week with a few modifications.
+The for loop was modified to reflect the multiplication of the rectangle size by the lcg_value().
+  $x = lcg_value();     *  800;
+  $y = lcg_value();     *  800;
+After the closing of the if statement, but before the closing of the for loop insert the function to display the plotted points using pixels. imagesetPixel draws a pixel at the specified coordinate using an image resource parameter ,  x-coordinate and y-coordinate and color identifier.
+  imagesetPixel($img, $x, $y, purple);
+The Monte Carlo Pi function now displays in a graphical format. To add the original output text to the bottom of the graph use the imagestring() function. This function draws a horizontal string at given coordinates.
+It takes six parameters listed below.
+  * $img is the image resource returned by imagecreatetruecolor
+  * Font uses a number between 1-5 for built-in fonts in latin2 encoding
+  * The x-coordinate of the upper left corner
+  * The y-coordinate of the upper left corner
+  * The width (600) and height (600) of the arc
+  * The string to be written to the specified coordinates
+  * A color identifier chosen from our virtual palette ($green)
+Example:
+  imagestring($img, 3, 75, 820, “# in the square: $iterations”,  $green);
+  imagestring($img, 3, 75, 840, “# in the circle: $init”,  $green);
+  imagestring($img, 3, 75, 860, “pi =  $pi”,  $green);
+This concludes the breakdown of the code for Monte Carlo Pi.
+====APRIL 6, 2016====
+==Week 11==
+Bonus post.
+Our next project is Show and Tell. Unfortunately, it does not involve exploding volcano’s, slimy frogs, or baking soda and vinegar rockets.  However, it does allow for some creative thinking in PHP. The objective is to pick something interesting in relation to PHP and implement/explore it to gain a deeper understanding of it’s functionality.  The final presentation is in a web-accessible format for all to view.
+Some ideas I am interested in exploring.
+  * Create a PHP photo gallery using the exif function
+  * Databases and PHP
+  * Create a PHP/MySQL powered forum from scratch
+  * Management Systems
+Not sure what direction I want to take at this point.
+====APRIL 13, 2016====
+==Week 12==
+For the Show and Tell project I chose to explore photo galleries using PHP. In my explorations I found several ways to implement a photo gallery using strictly PHP, PHP and jQuery, PHP and SQL, and PHP and Ajax. In addition, galleries have multiple storage options. Some galleries are created and stored in databases using MySQL and other galleries are created and stored in folders on the web server. I found a really old but very informative tutorial on creating an automated PHP gallery system using PHP, MySQL, GD and ImageMagick on the SitePoint website. It walks you through the process of setting up the database schema and building a browser-based uploading system, which sets up an index within the tables, stores the files, and automatically builds thumbnails.
+Ultimately, I settled on something a little less complicated for a first timer. I chose to create a photo gallery using strictly PHP. I am working through the code to display the images as thumbnails until clicked where they are displayed full size. I need to upload some images to the server to test the code. I anticipate a good amount of troubleshooting to get everything processing correctly. Also, I need to figure out how to create the thumbnails. I have seen code that automatically does this process, which I’ll have to explore further. If I can get the initial photo gallery working I’d like to attempt to add a watermark feature to each image, but that is not a critical component at this time.
+====APRIL 20, 2016====
+==Week 13==
+The end of the semester is fast approaching as noted by the influx of final papers/projects being deployed. In fact, our very own EoCE has just deployed. Before delving to depths of the abyss with this experience I will take one last post to explain the code associated with the Show and Tell project that I am working on.
+First up is the variable declaration. These variables are used to declare the columns displayed, location of the thumbnails, and location of the full size images used in the gallery.
+  $images = "image_gallery/";  // Location of thumbnails
+  $big    = "big/";  // Location of full size images
+  $cols   = 2;  // Number of displayed columns
+$images builds the contact sheet or “thumbnails”.
+Next step is to open the directory containing the images and loop through it to add the image files to an array. The first line of the if statement opens the directory where all of the images are stored. The while condition loops over the directory and adds every file it finds to an array called $files[]. The readdir function reads entries from the directory handle and returns the name of the next entry in the directory. Entries are returned in the order they are stored by the filesystem. Any directory entry name that evaluates to FALSE will stop the loop. The nested if statement prevents the . (the current directory), .. (the directory one level up), and the $big directory from being added to the array. If displayed in the browser, they would show as broken links. Any file in the $images directory is added to the array and rendered as an image so be careful what you place here. The closedir function closes the directory handle opened by the opendir function.
+  if ($handle = opendir($images)) {
+    while (false !== ($file = readdir($handle))) {
+       if ($file != "." && $file != ".." && $file !=       rtrim($big,"/")) {
+           $files[] = $file;
+       }
+   }
+   closedir($handle);
+  }
+Now it’s time to output the table that displays the images. The goal here is to display the thumbnails as a contact sheet while linking each to its full size image. The first echo statement outputs the first part of the table. The first line in the for loop tests whether $colCtr (initialized to 0 before the loop) is of equal value to $col (number of columns to display). If yes, the table row closes, a new row is opened and an hr line break is used to separate the rows. The next echo statement creates a link to the full size images. The output is an a href attribute that specifies the link’s destination. In this case the link is built using the variables defined earlier in the code, $image, $big, and $file. The img src attribute outputs the image using $image. $file. The last step before closing the table is to increment the $colCtr variable to output the number of columns needed for displaying the images.
+  $colCtr = 0;
+  echo '<table width="100%" cellspacing="3"><tr>';
+  foreach($files as $file)
+  {
+  if($colCtr %$cols == 0)
+    echo '</tr><tr><td colspan="2"><hr /></td></tr><tr>';
+  echo '<td align="center"><a href="' . $images . $big .   $file . '">
+  <img src="' . $images . $file . '" /></a></td>';
+    $colCtr++;
+  }
+  echo '</table>' . "\r\n";
+In comparing the process of creating a basic photo gallery using PHP and HTML/CSS it appears PHP has the advantage. The code is more streamlined meaning it uses far less steps to accomplish the same end result.
+====APRIL 27, 2016====
+==Week 14==
+The countdown to the end of the semester is approaching warp speed. The end is nigh. It’s final crunch time for end of semester presentations and projects, which some are scrambling to complete. I am slowly whittling away at the EoCE. I have started 0x0, draw a picture reflecting your interpretation of “April showers bring May flowers.” Conceptually, I have an image floating around in my head and to date the “creation” has closely represented said image. The only constraints I foresee with this task is my indecisive nature steering me off the plank and into the abyss.
+I have discovered that the imagefilledpolygon function in PHP has the capability to draw a triangle using an array to define its points. My initial use for the triangle was to add texture to the grass section of the image, but after seeing the output I have discovered other uses for the imagefilledpolygon. Immediately after seeing the sharply pointed, pink object appear on the screen I wanted to use it to represent the sun’s rays. The challenge is figuring out how to wrap it around the outside edge of the imagefilledarc. This is something I need to explore as it may be beyond my skill level.
+I have also started thinking about the binary table as I feel this may cause me to bang my head against a wall. I am exploring methods and ideas but haven’t settled on something solid yet.
+====MAY 4, 2016====
+==Week 15==
+This entry marks the last week of classes for the semester and therefore the last blog post for PHP. It’s been a semester full of fun and exciting new explorations. I’ve learned that PHP is not just for querying a database, drawing pictures is an excellent way to learn a new programming language, and there is a whole world of memes that lure you into a time suck.
+Still working on the EoCE. Progress has slowed as I needed to focus on other courses, but with most other projects behind me I can return to drawing pictures, creating meme’s and binary tables.
@@ Line 694: / Line 946: @@
 Absolute mindbender.
+====MARCH 21, 2016====
+==Week 10==
+**Endianness and Etymology**
+The concept of Big-Endian and Little-Endian was first introduced by Danny Cohen in 1980 who derived his byte ordering names from a segment of Johnathan Swift’s “Gulliver’s Travels.”
+**Endianness Explained**
+Endianness is the arrangement or storage of bytes (binary data). Big-Endian is where the most significant byte of a multi-byte data field is stored at the lowest memory address. Little-Endian is where the least significant byte of a multi-byte data field is stored at the lowest memory address. Thus creating a Big vs Little feud. Fact: there are 256 unique values in 1 byte.
+Big-endian = B0 CF
+Little-endian = CF B0
+**Regular Expressions**
+A regular expression or regex is a sequence of characters that define a search pattern. Most commonly used with strings to perform pattern matching operations. Often considered a jacked up wildcard.
+Requirements:
+Know your data! If you do not know what you want, you have no business poking around the data. Knowing the data allows you to make more intelligent requests.
+Regex Symbols
+  . (dot) 	matches any single character
+  * 		O or more of the previous; cannot use by itself; pair it with something before it
+  [    ]	character class, match any one of the enclosed characters
+  [^  ]		inverted character class; do not match any one of the enclosed characters
+  \< 		match start of word
+  \>		match end of word
+  ^		match start of line
+  $		match end of line
+  ? 		match the preceding 0 or 1 times. 1 time optionality - It’s either there or not. Pair it.
+  + 		1 or more of the previous. Not all tools support this.
+The grep command is used to match patterns within a text file.
+__Example__
+Wander into the dictionary and start searching.
+Find all of the 4 character lines in the dictionary.
+  cat words | grep  ‘^….$’ | wc -l
+Extended Regex Symols
+          (   )  	Group together
+  sed ->  \( \) 	Group together
+            | 	        Logical OR
+The egrep command is used to match patterns within a text file.
+__Example__
+Wander into the dictionary and start searching.
+Find all words that start with M followed by ic, ou.
+  cat words | egrep ‘^m(ou|ic)’ | wc -l
+**Project Notes:**
+Preliminary investigation yields the following results:
+Absolute mindblender.
+====MARCH 28, 2016====
+==Week 11==
+It’s break week and I have taken a chunk of time to organize my notes from the last few weeks so this post is going to be a modge podge of things that failed to make it in the previous entries.
+**Data**
+All binary is text data, but not all text is binary.
+Text—vi, cat, head, tail, echo all deal with text.
+Binary—not encoded in ASCII.
+**All About the Double 'd'**
+The 'dd' command is your main tool for the udr0 project and it makes an appearance in udr1 when overlaying the backup onto disk.image. 'dd' (data dump or data duplicator) is cat on steroids. It reads from stdin and writes to stdout unless otherwise specified by the if (input file) and of (output file) options. To use give it a set of flags. A report of the ‘records in’ and ‘records out’ is displayed as an output message after the 'dd' command executes. ‘dd’ likes decimal data (base 10) if not in base 10 convert first.
+**Syntax of ‘dd’ command:**
+  dd if=<source file name> of=<target file name [Options]
+**Examples:**
+  dd if=/etc/motd of=newfile bs=512 count=1
+The ‘if’ stands for input file, ‘of’ stands for output file, ‘bs’ stands for the block size (number of bytes to be read/write at a time), and ‘count’ refers to the number of input blocks to be copied.
+The default value for input and output block sizes is 512 bytes (one sector)
+//To Use dd as cat://
+  dd if=/etc/motd of=/dev/tty
+//To Use dd as copy://
+  dd if=/etc/motd of=newfile
+**Project Notes:**
+//udr1—Data Recovery//
+New this year is a mind numbing data recovery experience. This week’s project delves deep into the realm of abstraction and roots around the topic of raw data management and data recovery in relation to hard drives and partition tables.
+__Useful Information__
+The Master Boot Record (MBR) is located on the first sector (one sector is equal to 512 bytes) of the hard drive. It contains the Master (or Primary) Partition Table information needed to determine the starting sectors and overall sizes of each partition needing extraction. The primary partition table is 64 bytes of the 512 byte MBR. The Partition Table contains four 16 byte entries and thus can have no more than four Primary partitions.
+//Restoration://
+The dd command has the ability to modify data in a specified place.
+//Example://
+dd if=<source file name> of=<target file name> bs=1 conv=notrunc
+This command overwrites the first 512 bytes of a file. The notrunc option means do not truncate the output file. If the target file already exists, replace the specified bytes and do not touch the rest of the target file.
+To be continued…
+====APRIL 6, 2016====
+==Week 11==
+Bonus Post.
+Coming off break week, I find myself grappling with the abstract concepts of the udr series of labs. Each progression in the series catapults you further down the rabbit hole. It is clear that my natural sandbox is not in data storage or recovery at the bit level. I am more comfortable dissecting work from Willem de Kooning, Franz Kline or Jackson Pollock during the Abstract Expressionism period.
+As I muddle through these labs, I find I am gaining a deeper understanding of  how partition tables and data packets work. Two extremely useful commands in the labs’ arsenal are dd and search. These are your friends throughout the duration of this mind numbing, but educational experience. The most difficult concept was finding a starting point. Once found things started to make more sense and flow smoother.  If there is a follow-up post then I survived the udr series.  Otherwise, I never found my way out of the rabbit hole.
+====APRIL 13, 2016====
+==Week 12==
+Review week and more bash scripting. We’ve been adding more bash examples to our arsenal of scripting files this week. This should prove useful with our next project on grade calculations. Remember that the proper use of quotes matters and backticks are not single quotes. Single quotes are literal quotes meaning that it searches for what is literally within the ‘quotes.’
+**Project Notes:**
+Upr0—UNIX Permission Review
+This week’s project schooled procrastinator’s in the art of time management while reviewing file permissions. A concept we explored early in the semester and something we are currently using with bash scripting.
+Files in Unix have three permission attributes: owner, group, and other or world. Owner permissions determine what privileges the file owner has on the file. Group permissions determine what privileges a user in a group that a file belongs to has on the file. Other or world permissions determine what privileges all other users have on the file. Each file permission is broken into groups consisting of three characters per group. The three characters are read, write, and execute. The first two are self-explanatory and the execute bit grants the user privileges to run a file as a program. All three are associated with a numerical value—read (4), write (2), execute (1), which is used to change the file permission. A dash (-) in the place of a numerical value represents nothing or (0). Adding up the values in each group results in a value with a range between 0 and 7.
+Example:
+  srwx--x-w- (712)
+The ‘s’ is the file type and changes with depending on the file. Watch out for these in the project they can trip you up at first. The ‘rwx’ represents a value of 7 and grants access to all privileges in the owner field.  The ‘--x’ grants executable access to members of a group owning the file and ‘-w- ‘gives write privileges only to all other users.
+Special file permissions surface about halfway through the project. These permissions allow the user running an executable file to assume the ID of the owner of the file. The setUID permission has a numerical value of 4 and is displayed in owner permissions in the executable field. The setGID has a numerical value of 2 and is displayed in the group permissions in the executable field. The sticky bit has a numerical value of 1 and is displayed in the other or world permissions in the executable field. If an executable bit is set the setUID or setGID represented by an ‘s’ will be lowercase and if no executable fields exists, then the bit is uppercase. The same rule applies to the sticky bit except it is represented by a ‘t’.
+Example:
+  dr-sr-srwt (7557)
+The file type field is set to a directory as noted by the 'd' at the beginning of the file permission. The ‘r-s’ represents a value of 5 for the regular permissions and 4 for the special permissions and the ‘rwt’ presents 7 for the regular permissions and 1 for the special permissions. Add up the special permissions and put that value in front of the regular permissions.
+The chmod command is used to change the permissions of a file or directory. Specify the numerical permission settings followed by the file or directory name you want to modify.
+  chmod 6777 file1.txt
+This concludes the review session.
+====April 20, 2016====
+===Week 13===
+For the last two weeks or so we have been exploring the use of regular expressions. Regular expressions are used in conjunction with several different commands such as sed, ed, awk, and grep. We have focused primarily on sed and grep. Here is a brief recap of the commands and their syntax.
+The grep command mentioned in an earlier post, but not fully explored searches standard input or text within a file for string patterns and prints any lines matching the specified pattern to stdout (the terminal).
+It’s syntax is:
+  grep [options] PATTERN [FILE…]
+  grep [options] [-e PATTERN | -f FILE] [FILE…]
+The sed command or stream editor is invoked by sending data to it through a pipe. The data sent passes through sed and goes to stdout without changing the input file.
+It’s syntax is:
+  /pattern/action
+Where pattern is a regular expression and action is a command given. The slash characters are used as delimiters. Sed is line oriented meaning if you are using the substitute (s) command it will only replace the first instance of the string being replaced. If you have an input line that reads “One fish, Two fish, Red Fish, Blue fish.” and you want to replace “fish” with “FISH” by default sed will only replace the first instance of fish with FISH.
+**Miscellaneous Notes**
+Single quotes are literal quotes. Searches for what is literally within the ‘quotes.’
+Printf “%&s “ “ “   right justifies by default. “%$s “ ” ” adds padding value.
+Printf “%-3s ”   Negates padding value (left justify)
+====April 27, 2016====
+===Week 14===
+The end of the semester is upon us and the EoCE for UNIX has been deployed. Gulp! I have started to tackle the first problem, 0x0: Script Analysis, and found that once I created and ran the script I had a much better understanding of what it was doing. With my nerves eased I was able to settle in and begin answering the questions pertaining to the various components of the script. I have my responses captured in screen shots and randomly written on paper I just need to add them to the blog. This brings me to the next problem, 0x1: super puzzlebox 2 turbo, I had a feeling we weren’t done with the puzzlebox yet.  I equate these to solving a Rubik’s cube. For some people finding the solution only takes seconds while others may spend minutes, hours or even days twisting the colorful cube to perfection. The last category of people spends many frustrating hours twisting that cube until they have two squares left to align. They are forced with the ultimate decision do I keep twisting knowing that I will destroy all progress or do I carefully peel back the corner of the sticker? I will know my fate once I open and start unraveling the puzzlebox.
+====MAY 4, 2016====
+==Week 15==
+This entry marks the last week of classes for the semester and therefore the last blog post for UNIX. It’s been a crazy, whirlwind semester filled with sharp twists and mind bending (numbing) experiences. Entering the course with much trepidation at the suggestion of a higher power I initially expected to flail and run. Over the course of the last 14 weeks I’ve gained what feels like an enormous amount of knowledge about a new OS. My skill level is still firmly planted in beginner mode, but I can at least nod and say I know about the super powers of the dd command.
+I am still working on the EoCE. Progress has slowed or come to a screeching halt as I needed to focus on other courses, but with most other projects behind me I can return to puzzle boxes and scripting.

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