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bollwyvl/2019-01-03-Loop-de-loop.ipynb

Created January 3, 2019 22:22
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  1. bollwyvl created this gist Jan 3, 2019.
    138 changes: 138 additions & 0 deletions 2019-01-03-Loop-de-loop.ipynb
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    {
    "cells": [
    {
    "cell_type": "code",
    "execution_count": 1,
    "metadata": {},
    "outputs": [],
    "source": [
    "from tornado.ioloop import IOLoop, PeriodicCallback\n",
    "from tornado.httpclient import AsyncHTTPClient\n",
    "from tornado import gen\n",
    "from tornado.platform.asyncio import to_tornado_future\n",
    "from asyncio import sleep\n",
    "import time\n",
    "from ipywidgets import FloatSlider, Checkbox, HBox"
    ]
    },
    {
    "cell_type": "markdown",
    "metadata": {},
    "source": [
    "IOLoop has all the goodies."
    ]
    },
    {
    "cell_type": "code",
    "execution_count": 2,
    "metadata": {},
    "outputs": [],
    "source": [
    "loop = IOLoop.instance()"
    ]
    },
    {
    "cell_type": "markdown",
    "metadata": {},
    "source": [
    "If you name your functions, and then call them indirectly, you can hack on them while it's running."
    ]
    },
    {
    "cell_type": "code",
    "execution_count": 6,
    "metadata": {},
    "outputs": [],
    "source": [
    "def increment(*args, **kwargs):\n",
    " if running.value:\n",
    " x.value += 3\n",
    " loop.call_later(0.5, increment)"
    ]
    },
    {
    "cell_type": "markdown",
    "metadata": {},
    "source": [
    "`stdout` doesn't work so great, but widgets are fine."
    ]
    },
    {
    "cell_type": "code",
    "execution_count": 4,
    "metadata": {},
    "outputs": [
    {
    "data": {
    "application/vnd.jupyter.widget-view+json": {
    "model_id": "0f8537501199496895791ac4f02f7db6",
    "version_major": 2,
    "version_minor": 0
    },
    "text/plain": [
    "HBox(children=(Checkbox(value=False, description='running'), FloatSlider(value=0.0)))"
    ]
    },
    "metadata": {},
    "output_type": "display_data"
    }
    ],
    "source": [
    "running = Checkbox(description=\"running\")\n",
    "x = FloatSlider()\n",
    "running.observe(lambda _: running.value and loop.add_callback(lambda: increment()), \"value\")\n",
    "\n",
    "HBox([running, x])"
    ]
    },
    {
    "cell_type": "markdown",
    "metadata": {},
    "source": [
    "You can also set up a more regular clock with `PeriodicCallbac`"
    ]
    },
    {
    "cell_type": "code",
    "execution_count": 7,
    "metadata": {},
    "outputs": [],
    "source": [
    "def tick():\n",
    " if running.value:\n",
    " x.value -= 0.5"
    ]
    },
    {
    "cell_type": "code",
    "execution_count": 8,
    "metadata": {},
    "outputs": [],
    "source": [
    "cb = PeriodicCallback(lambda: tick(), 1000)\n",
    "cb.start()"
    ]
    }
    ],
    "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": "3.6.7"
    }
    },
    "nbformat": 4,
    "nbformat_minor": 2
    }