{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# [`for` loops](https://docs.python.org/3/tutorial/controlflow.html#for-statements)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Looping lists" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "my_list = [1, 2, 3, 4, 'Python', 'is', 'neat']\n", "for item in my_list:\n", " print(item)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### `break`\n", "Stop the execution of the loop." ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "for item in my_list:\n", " if item == 'Python':\n", " break\n", " print(item)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### `continue`\n", "Continue to the next item without executing the lines occuring after `continue` inside the loop." ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "for item in my_list:\n", " if item == 1:\n", " continue\n", " print(item)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### `enumerate()`\n", "In case you need to also know the index:" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "for idx, val in enumerate(my_list):\n", " print('idx: {}, value: {}'.format(idx, val))" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Looping dictionaries" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "my_dict = {'hacker': True, 'age': 72, 'name': 'John Doe'}\n", "for val in my_dict:\n", " print(val)" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "for key, val in my_dict.items():\n", " print('{}={}'.format(key, val))" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## `range()`" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "for number in range(5):\n", " print(number)" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "for number in range(2, 5):\n", " print(number)" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "for number in range(0, 10, 2): # last one is step\n", " print(number)" ] } ], "metadata": { "kernelspec": { "display_name": "Python 3", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.5.4" } }, "nbformat": 4, "nbformat_minor": 2 }