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Exercises/Intro2Python/Module2-Conditionals.ipynb

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+    "## Conditionals and code indendation\n",
+    "In Python, code blocks are separated by use of indentation. See the defintion of an `if`-statement below:\n",
+    "\n",
+    "### Syntax of conditional blocks\n",
+    "    \n",
+    "```python\n",
+    "if condition:\n",
+    "    # Code goes here (must be indented!)\n",
+    "    # Otherwise, IndentationError will be thrown\n",
+    "\n",
+    "# Code placed here is outside of the if-statement    \n",
+    "```\n",
+    "\n",
+    "Where evaluation of `condition` must return a boolean (`True` or `False`).\n",
+    "\n",
+    "\n",
+    "> **Remember:**\n",
+    "> 1. The `:` ***must*** be present after `condition`.\n",
+    "> 2. The line immediately after `:` ***must*** be indented. \n",
+    "> 3. The `if`-statement is ***exited by reverting the indentation*** as shown above.\n",
+    "\n",
+    "This is how Python interprets the code as a block.    \n",
+    "\n",
+    "The same indentation rules are required for all types of code blocks, the `if`-block above is just an example. Examples of other types of code blocks are `for` and `while` loops, functions etc.\n",
+    "\n",
+    "All editors will automatically make the indentation upon hitting enter after the `:`, so it doesn't take long to get used to this. "
+   ]
+  },
+  {
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+    "## Conditional statements - examples\n",
+    "\n",
+    "### `if`-statements\n",
+    "An `if`-statement has the following syntax:"
+   ]
+  },
+  {
+   "cell_type": "code",
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+     "text": [
+      "x is larger than 1\n"
+     ]
+    }
+   ],
+   "source": [
+    "x = 2 # Example variable assignment\n",
+    "if x > 1: # Check if x is greater than 1\n",
+    "    print('x is larger than 1') # Print message if condition is true"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### `if` / `else`-statements"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
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+     "text": [
+      "y is less than or equal to 1\n"
+     ]
+    }
+   ],
+   "source": [
+    "#an if-else statement example. This will execute one block of code if the condition is true, and another block if it is false.\n",
+    "\n",
+    "y = 1 # Another example variable assignment, make example where we set the if value to a variable...\n",
+    "if y > 1: # Check if y is greater than 1\n",
+    "    print('y is larger than 1') # Print message if condition is true\n",
+    "else:\n",
+    "    print('y is less than or equal to 1') # Print message if condition is false"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### `if` / `elif` / `else`"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "z is less than 1\n"
+     ]
+    }
+   ],
+   "source": [
+    "#an if-elif-else statement example. This will check multiple conditions in sequence.\n",
+    "\n",
+    "z = 0 # Another example variable assignment\n",
+    "if z > 1: # Check if z is greater than 1\n",
+    "    print('z is larger than 1') # Print message if condition is true\n",
+    "elif z < 1: # Check if z is less than 1 using the elif statement\n",
+    "    print('z is less than 1') # Print message if the elif condition is true\n",
+    "else: # This block executes if none of the above conditions are true\n",
+    "    print('z is equal to 1') # Print message if z is equal to 1"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "An unlimited number of `elif` blocks can be used in between `if` and `else`."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Exercise 1\n",
+    "If the string below has more than 100 characters, print *\"String has more than 100 characters\"*, otherwise print *\"String has less than or exactly 100 characters\"*.\n",
+    "~~~python\n",
+    "string = 'There are approximately 114 SNOTEL sites in Utah, as a part of the Natural Resouces Conservation Service (NRCS) and ~150 USGS NWIS streamflow monitoring gages.'\n",
+    "~~~"
+   ]
+  },
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+   "cell_type": "code",
+   "execution_count": null,
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+  },
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+   "metadata": {},
+   "source": [
+    "# Exercise 2\n",
+    "Print the number of space characters in `string` from above. "
+   ]
+  },
+  {
+   "cell_type": "code",
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+    "# Exercise 3\n",
+    "Create the variables\n",
+    "\n",
+    "```python\n",
+    "letter1 = 'USGS sites'\n",
+    "letter2 = 'SNOTEL sites'\n",
+    "```\n",
+    "\n",
+    "Convert this pseudo code to a Python program:\n",
+    "\n",
+    "```python\n",
+    "if there are more occurrences of letter1 than letter2 in string:\n",
+    "    print(\"There are more {insert_letter1} than {insert_letter2} \")\n",
+    "    \n",
+    "elif there are more occurrences of letter2 than letter1 in string:\n",
+    "    print(\"There are more {insert_letter2} than {insert_letter1} \")\n",
+    "\n",
+    "else:\n",
+    "    print(\"There are exactly the same number {insert_letter1} and {insert_letter2}\")\n",
+    "```"
+   ]
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+   "metadata": {},
+   "source": [
+    "# Exercise 4\n",
+    "Test the program you wrote above with different combinations of letters for the variables `letter1` and `letter2`. \n",
+    "Implement a print message of the actual number of occurrences."
+   ]
+  },
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+   "metadata": {},
+   "source": [
+    "Next [Module](./Module3-DataStructures.ipynb)"
+   ]
+  },
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