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Niolon merged 3 commits into from
Mar 2, 2026
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Improve advanced string manipulation section #66

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45b3b5d
Improve advanced string manipulation section
parnumeric Feb 26, 2026
8d4fef6
Drop exceptions in advanced string manipulation and restore notes sli…
parnumeric Mar 2, 2026
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Resolve merge conflicts
parnumeric Mar 2, 2026
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180 changes: 119 additions & 61 deletions Intermediate.ipynb
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Original file line number Diff line number Diff line change
Expand Up @@ -217,7 +217,7 @@
"editable": false
},
"source": [
"# <ins>**1.**</ins> Recap"
"# <ins>1.</ins> Recap"
]
},
{
Expand Down Expand Up @@ -4246,6 +4246,62 @@
"# <ins>7.</ins> Advanced string manipulation"
]
},
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"source": [
"## String Methods - Working with String Objects"
]
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"In Python, strings are objects, and objects have **methods** - functions that belong to and operate on that object.\n",
"\n",
"**Syntax**: `string_object.method_name(arguments)`\n",
"\n",
"Key characteristics:\n",
"- Methods are called using _dot notation_: `variable.method()`\n",
"- String methods return a **new string** (strings are immutable)\n",
"- The original string is never modified\n",
"- You must assign the result if you want to keep it\n",
"\n",
"**Example:**"
]
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"source": [
"text = \"hello world\"\n",
"result = text.upper() # Creates new string\n",
"print(text) # Still \"hello world\" \n",
"print(result) # \"HELLO WORLD\""
]
},
{
"cell_type": "markdown",
"id": "c9016a2e-dee1-4030-a1a0-8e519a84be6f",
Expand All @@ -4257,10 +4313,11 @@
"editable": false
},
"source": [
"* Adjusting case\n",
"* Formatting strings\n",
" - _Note_: Modification requires assignment, because these functions return a copy, not modifying the original string\n",
"* Quering the existence, replacing, splitting"
"Common categories of string methods we'll explore:\n",
"- **Finding/searching**: `find()`, `index()`\n",
"- **Checking**: `startswith()`, `endswith()`\n",
"- **Transforming**: `replace()`, `upper()`, `lower()`, `capitalize()`, `strip()`\n",
"- **Splitting/joining**: `split()`, `join()`"
]
},
{
Expand All @@ -4274,33 +4331,28 @@
"editable": false
},
"source": [
"## Finding values \n",
"* `find()` and `index()` both return index of a substring,\n",
" - `index()` raises a `ValueError` exception when not found (_exception handling_)\n",
" - `find()` returns `-1` when a values was not found\n"
"## Finding/searching string methods"
]
},
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"source": [
"line = \"the quick brown fox jumped over a lazy dog\"\n",
"print(line.find('fox'))\n",
"print(line.index('fox'))"
"These methods help you locate substrings within a string, returning their position or checking for their presence:\n",
"* `index()`\n",
"* `find()`"
]
},
{
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"id": "134c6eba-8897-4ee8-a6e5-f3740a0a4d21",
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"slide_type": ""
Expand All @@ -4309,13 +4361,15 @@
},
"outputs": [],
"source": [
"print(line.find('wombat'))"
"line = \"the quick brown fox jumped over a lazy dog\"\n",
"print(line.find('fox'))\n",
"print(line.index('fox'))"
]
},
{
"cell_type": "code",
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Expand All @@ -4324,10 +4378,7 @@
},
"outputs": [],
"source": [
"try:\n",
" print(line.index('wombat'))\n",
"except ValueError:\n",
" print(\"A wombat isn't mentioned in the text\")"
"print(line.find('wombat'))"
]
},
{
Expand All @@ -4341,7 +4392,7 @@
"editable": false
},
"source": [
"## Checking conditions on strings"
"## Checking string methods"
]
},
{
Expand All @@ -4355,7 +4406,9 @@
"editable": false
},
"source": [
"* Checking whether a string starts or ends a certain way is really common and easy"
"These methods return boolean values (`True` or `False`) to verify if a string matches certain patterns or criteria:\n",
"* `startswith(substring)`\n",
"* `endswith(substring)`"
]
},
{
Expand Down Expand Up @@ -4399,13 +4452,13 @@
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"source": [
"* The canonical way to search a string (if not interested in the index):"
"The canonical way to search a string (if not interested in the index):"
]
},
{
Expand Down Expand Up @@ -4435,7 +4488,25 @@
"editable": false
},
"source": [
"## Replacing a value:"
"## Transforming string methods"
]
},
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"source": [
"These methods create modified versions of strings by replacing content, changing case, or removing unwanted characters. _**Remember**: strings are immutable, so these methods always return a new string._\n",
"* `replace(old, new)`\n",
"* `upper()`\n",
"* `lower()`\n",
"* `capitalize()`\n",
"* `strip()`"
]
},
{
Expand All @@ -4455,20 +4526,6 @@
"print(line.replace('brown', 'red'))"
]
},
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"source": [
"## Bring all words to a common case"
]
},
{
"cell_type": "code",
"execution_count": null,
Expand All @@ -4488,20 +4545,6 @@
"print(arc_update.capitalize())"
]
},
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"source": [
"## Removing white space"
]
},
{
"cell_type": "code",
"execution_count": null,
Expand Down Expand Up @@ -4531,7 +4574,22 @@
"editable": false
},
"source": [
"## Extracting/concatenating the individual words or parts"
"## Splitting/joining string methods"
]
},
{
"cell_type": "markdown",
"id": "71a4546c",
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"source": [
"These methods allow you to break strings apart into lists of substrings, or combine lists of strings into a single string. They're particularly useful for parsing text data or formatting output:\n",
"* `split(separator)` - splits string into a list at each occurrence of separator (defaults to whitespace)\n",
"* `join(iterable)` - joins elements of an iterable into a single string with the string as separator"
]
},
{
Expand Down Expand Up @@ -4566,7 +4624,7 @@
"editable": false
},
"source": [
"The operation in the other direction is `a_string.join()` where `a_string` is placed between every string of a list"
"The `join` operation is `a_string.join()` where `a_string` is placed between every string of a list"
]
},
{
Expand Down Expand Up @@ -5848,7 +5906,7 @@
"name": "python",
"nbconvert_exporter": "python",
"pygments_lexer": "ipython3",
"version": "3.12.3"
"version": "3.13.0"
}
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"nbformat": 4,
Expand Down
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