update 03 assignment

Author: pssachdeva

Day_1/03_Variables_Assignment.ipynb

@@ -2,9 +2,7 @@
  "cells": [
   {
    "cell_type": "markdown",
-   "metadata": {
-    "collapsed": true
-   },
+   "metadata": {},
    "source": [
     "# Variables and Assignment\n",
     "\n",
@@ -13,25 +11,23 @@
     "- Challenges: 10 min\n",
     "\n",
     "**Questions**\n",
-    "- \"How can I store data in programs?\"\n",
+    "- How can I store data in programs?\n",
     "\n",
     "**Learning Objectives**\n",
-    "- \"Write programs that [assign](https://github.com/dlab-berkeley/python-intensive/blob/master/Glossary.md#assign) scalar values to variables and perform calculations with those values.\"\n",
-    "- \"Correctly trace value changes in programs that use scalar assignment.\"\n",
+    "- Write programs that [assign](https://github.com/dlab-berkeley/python-intensive/blob/master/Glossary.md#assign) scalar values to variables and perform calculations with those values.\n",
+    "- Correctly trace value changes in programs that use scalar assignment.\n",
     "\n",
     "* * * * *"
    ]
   },
   {
    "cell_type": "markdown",
-   "metadata": {
-    "collapsed": true
-   },
+   "metadata": {},
    "source": [
-    "## Use variables to store values.\n",
+    "## Use variables to store values\n",
     "\n",
-    "*   Variables are names for values.\n",
-    "*   In Python the `=` symbol assigns the value on the right to the name on the left.\n",
+    "*   Variables are placeholders for useful values. They have meaningful names, which makes it easier to reuse those values.\n",
+    "*   In Python, the `=` symbol assigns the value on the right to the name on the left.\n",
     "*   The variable is created when a value is assigned to it.\n",
     "*   Here's Python code that assigns an age to a variable `age`\n",
     "    and a name in quotation marks to a variable `first_name`.\n"
@@ -51,16 +47,16 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "*   Variable names:\n",
-    "    *   cannot start with a digit\n",
-    "    *   cannot contain spaces, quotation marks, or other punctuation\n",
-    "    *   *may* contain an underscore (typically used to separate words in long variable names)\n",
-    "*   Underscores at the start like `__alistairs_real_age` have a special meaning\n",
-    "    so we won't do that until we understand the convention.\n",
+    "*   Variable names must follow a few rules:\n",
+    "    *   They cannot start with a digit.\n",
+    "    *   They cannot contain spaces, quotation marks, or other punctuation.\n",
+    "    *   They *may* contain an underscore (typically used to separate words in long variable names).\n",
+    "*   Underscores at the beginning of a variable name, such as `__first_name`, have a special meaning.\n",
+    "    We won't use this format until we understand the convention.\n",
     "\n",
-    "## Use `print` to display values.\n",
+    "## Use `print` to display values\n",
     "\n",
-    "*   Python has a built-in function called `print` that prints things as text.\n",
+    "*   Python has a built-in function called `print` that prints output given some inputs.\n",
     "*   Call the function (i.e., tell Python to run it) by using its name.\n",
     "*   Provide values to the function (e.g., things to print) in parentheses.\n"
    ]
@@ -78,17 +74,17 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "*   `print` automatically puts a single space between items to separate them.\n",
-    "*   And wraps around to a new line at the end.\n",
+    "*   `print` automatically puts a single space between different inputs to separate them.\n",
+    "*   It also adds a new line at the end. Try entering multiple `print` statements to see this.\n",
     "\n",
-    "## Variables persist between cells.\n",
+    "## Variables persist between cells\n",
     "\n",
     "*   Variables defined in one cell exist in all following cells.\n",
     "*   Notebook cells are just a way to organize a program:\n",
     "    as far as Python is concerned,\n",
     "    all of the source code is one long set of instructions.\n",
     "\n",
-    "## Variables must be created before they are used.\n",
+    "## Variables must be created before they are used\n",
     "\n",
     "*   If a variable doesn't exist yet, or if the name has been mis-spelled,\n",
     "    Python reports an error.\n"
@@ -110,15 +106,15 @@
     "*   The last line of an error message is usually the most informative.\n",
     "*   We will look at error messages in detail [later](https://github.com/dlab-berkeley/python-intensive/blob/master/Day_3/15_Errors.ipynb).\n",
     "\n",
-    "## Python is case-sensitive.\n",
+    "## Python is case-sensitive\n",
     "\n",
     "*   Python thinks that upper- and lower-case letters are different,\n",
     "    so `Name` and `name` are different variables.\n",
     "*   Again,\n",
     "    there are conventions around using upper-case letters at the start of variable names\n",
     "    so we will use lower-case letters for now.\n",
     "\n",
-    "## Use meaningful variable names.\n",
+    "## Use meaningful variable names\n",
     "\n",
     "*   Python doesn't care what you call variables as long as they obey the rules\n",
     "    (alphanumeric characters and the underscore).\n"
@@ -145,7 +141,7 @@
     "## Variables can be used in calculations.\n",
     "\n",
     "*   We can use variables in calculations just as if they were values.\n",
-    "    *   Remember, we assigned 42 to `age` a few lines ago."
+    "*   Remember, we assigned 42 to `age` a few lines ago."
    ]
   },
   {
@@ -158,56 +154,14 @@
     "print('Age in three years:', age)"
    ]
   },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "## Namespace\n",
-    "\n",
-    "To display the scope namespace of variables we can use the `dir` function:\n"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "dir()"
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "To get a dictionary of local variables, we can call `locals`:"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "locals()"
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "With both functions, we see a lot of predefined variables in the Python and Jupyter environment, but also `age`, `first_name`, `flabadab`, and `ewr_422_yY`, which we created above."
-   ]
-  },
   {
    "cell_type": "markdown",
    "metadata": {},
    "source": [
     "# `%who` and `%whos`\n",
     "\n",
-    "If `dir()` and `locals()` are too confusing, try these [magic](https://towardsdatascience.com/top-10-magic-commands-in-python-to-boost-your-productivity-1acac061c7a9) [commands](https://ipython.readthedocs.io/en/stable/interactive/magics.html) instead. \n",
-    "\n",
-    "`%who` will return the variables you have saved:"
+    "* There are a couple \"magic\" commands you can run to help you keep track of your variables.\n",
+    "* `%who` will return the variables you have saved:"
    ]
   },
   {
@@ -223,7 +177,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "`%whos` will display the variables, their type, and information about the data they contain:"
+    "* `%whos` will display the variables, their type, and information about the data they contain:"
    ]
   },
   {
@@ -239,10 +193,10 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "## Challenge 1: Making and Printing Variables\n",
+    "## Challenge 1: Creating and Printing Variables\n",
     "\n",
-    "1. Make 3 variables: `name` (with your full name), `city` (where you were born) and `year` (when you were born).\n",
-    "2. Print these three variables so that it prints `[your name] was born in [city] in [year]`"
+    "1. Create 3 variables: `name` (with your full name), `city` (where you were born) and `year` (when you were born).\n",
+    "2. Print these three variables with the `print` function so that it prints `[your name] was born in [city] in [year]`"
    ]
   },
   {
@@ -258,7 +212,7 @@
    "source": [
     "## Challenge 2: Swapping Values\n",
     "\n",
-    "Draw a table showing the values of the variables in this program after each statement is executed.\n",
+    "Create a table showing the values of the variables in this program after each statement is executed.\n",
     "\n",
     "In simple terms, what do the last three lines of this program do?"
    ]
@@ -350,29 +304,22 @@
    "source": [
     "*****\n",
     "\n",
-    "## Keypoints\n",
+    "## Key Points\n",
     "\n",
-    "1. \"Use variables to store values.\"\n",
-    "2. \"Use `print` to display values.\"\n",
-    "3. \"Variables persist between cells.\"\n",
-    "4. \"Variables must be created before they are used.\"\n",
-    "5. \"Python is case-sensitive.\"\n",
-    "6. \"Variables can be used in calculations.\"\n",
-    "7. \"Use meaningful variable names.\""
+    "1. Use variables to store meaningful values.\n",
+    "2. Use `print` to display values.\n",
+    "3. Variables persist between cells.\n",
+    "4. Variables must be created before they are used.\n",
+    "5. Python is case-sensitive.\n",
+    "6. Variables can be used in calculations.\n",
+    "7. Use meaningful variable names."
    ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": []
   }
  ],
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python 3",
+   "display_name": "Python 3 (ipykernel)",
    "language": "python",
    "name": "python3"
   },
@@ -386,7 +333,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.8.3"
+   "version": "3.9.7"
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   "toc": {
    "base_numbering": 1,
@@ -432,5 +379,5 @@
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+ "nbformat_minor": 4
 }