PERCEPTRONS EREL SAUL ASSIGNMENT

projects/2-state-machines/Python and State Machines.ipynb

@@ -70,7 +70,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 5,
    "metadata": {
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@@ -142,11 +142,24 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 6,
    "metadata": {
     "collapsed": false
    },
-   "outputs": [],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Initial state: s1\n",
+      "Accepting? False\n",
+      "After a: s2\n",
+      "After ab: s3\n",
+      "Next steps: {'a': 's3'}\n",
+      "Accepting? True\n"
+     ]
+    }
+   ],
    "source": [
     "ab_a_ = StateMachine(\n",
     "    #We can define the states and edges in one go\n",
@@ -182,7 +195,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 7,
    "metadata": {
     "collapsed": true
    },
@@ -201,7 +214,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 10,
    "metadata": {
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    },
@@ -229,14 +242,17 @@
     "assert not check(test1(), \"hel\")\n",
     "assert not check(test1(), \"helloy\")\n",
     "assert not check(test1(), \"hih\")\n",
-    "assert not check(test1(), \"heyhey\")"
+    "assert not check(test1(), \"heyhey\")\n",
+    "\n"
    ]
   },
   {
    "cell_type": "markdown",
-   "metadata": {},
+   "metadata": {
+    "collapsed": true
+   },
    "source": [
-    "Next, define a state machine which accepts email addresses consisting only of the letter \"x\" and the symbols \"@\" and \".\" (in other words, you don't need a ton of edges). Devise tests for it below (try to be sinister---get a partner to come up with adversarial examples too)."
+    "# Next, define a state machine which accepts email addresses consisting only of the letter \"x\" and the symbols \"@\" and \".\" (in other words, you don't need a ton of edges). Devise tests for it below (try to be sinister---get a partner to come up with adversarial examples too)."
    ]
   },
   {
@@ -292,11 +308,20 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 12,
    "metadata": {
     "collapsed": false
    },
-   "outputs": [],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "ab\n",
+      "abc\n"
+     ]
+    }
+   ],
    "source": [
     "ab = \"a\" + \"b\"\n",
     "print(ab)\n",
@@ -313,11 +338,19 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 11,
    "metadata": {
-    "collapsed": true
+    "collapsed": false
    },
-   "outputs": [],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "['a', 'b', 'c']\n"
+     ]
+    }
+   ],
    "source": [
     "lst_abc = [\"a\",\"b\"] + [\"c\"]\n",
     "print(lst_abc)"

projects/2-state-machines/StateMachine_EREL_SAUL.ipynb

@@ -0,0 +1,93 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": true
+   },
+   "outputs": [],
+   "source": [
+    "#ASSIGNMENT 1.1\n",
+    "def check(sm, string):\n",
+    "    for s in string:\n",
+    "#for loop is used to go through each letter of the string        \n",
+    "        if s not in sm.out_edges():\n",
+    "#if statement here is used to check if the letter corresponds to the next edge. \n",
+    "#if it does NOT correspond to any out edges then it returns FALSE\n",
+    "            return False\n",
+    "#this basically means that it doesn't pass the conditions of the state machine\n",
+    "        sm.advance(s)\n",
+    "#if the selected letter does correspond to the any of the out edges we reassign the \n",
+    "#machine's state to be the target state denoted by that symbol, among the current out edges.\n",
+    "    return sm.is_terminal()\n",
+    "#if the string gets to this point than it means that all letter of the string has \n",
+    "#successfully passed the requirments and the state machine is in a terminal state \n",
+    "#since its current state is terminal\n",
+    "\n",
+    "\n",
+    "\n",
+    "#ASSIGNMENT 1.2\n",
+    "def test2():\n",
+    "    #(x+@x+\\.x+(\\.x+)*)\n",
+    "    return StateMachine([(\"s1\", \"x\", \"s2\"), (\"s2\", \"x\", \"s2\"), (\"s2\", \"@\", \"s3\"),\n",
+    "                         (\"s3\", \"x\", \"s4\"), (\"s4\", \"x\", \"s4\"), (\"s4\", \".\", \"s5\"),\n",
+    "                         (\"s5\", \"x\", \"s6\"), (\"s6\", \"x\", \"s6\"), (\"s6\", \".\", \"s7\"),\n",
+    "                         (\"s7\", \"x\", \"s6\")],\n",
+    "                        \"s1\",\n",
+    "                        [\"s6\"])\n",
+    "#this function pretty much works the same with the previous one, however this time instead having\n",
+    "#the out edges, we have created ourselves. We will also use the previous check function to basically\n",
+    "#check if the input string matches with the conditions we set. First, we check if the first letter is x.\n",
+    "#This is our number one condition. If it is, we continue to the second out edge. There are 2 options for the\n",
+    "#second edge, meaning the second letter can either be, once again, x or it can be the @ sign. Notice how \n",
+    "#the second edge with the x option has both s2's, (\"s2\", \"x\", \"s2\"). That's because there could be\n",
+    "#as many x's as the mail provider allows. So, if it's x again, then it will stay at the same edge until @ sign\n",
+    "#or any other sign/letter is used. If @ sign is used then it will go through edge 3 which expects x. After that, \n",
+    "#it can either take as many x's it can take or it can take a dot, which is edge 5. The same process goes with edges\n",
+    "#6 and 7. When the loop ends if the conditions are met the state machine terminates, if not it returns false. \n",
+    "\n",
+    "#ASSIGNMENT 2\n",
+    "def sample2(sm, length, sofar):\n",
+    "    # Each path of length 0 is either accepting or non-accepting;\n",
+    "    # in the former case we return [sofar] (the path) and in the latter [] (no path)\n",
+    "    if length == 0:\n",
+    "        if sm.is_terminal():\n",
+    "            return [sofar]\n",
+    "        else:\n",
+    "            return []\n",
+    "    state = sm.state\n",
+    "    results = []\n",
+    "    for sym in sm.out_edges():\n",
+    "        # for each edge: advance, sample, backtrack.\n",
+    "        sm.advance(sym)\n",
+    "        results = results + sample2(sm, length-1, sofar + sym)\n",
+    "        sm.state = state\n",
+    "    return results\n",
+    "\n"
+   ]
+  }
+ ],
+ "metadata": {
+  "anaconda-cloud": {},
+  "kernelspec": {
+   "display_name": "Python [Root]",
+   "language": "python",
+   "name": "Python [Root]"
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+    "name": "ipython",
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+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
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