Merge pull request #156 from kolbylyn/hw9

Hw9

kolbylyn/HW9.ipynb

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+{
+ "metadata": {
+ "name": "",
+ "signature": "sha256:3260a7771f92dd49feefef577b057348707f07966e6b31d57a2e8968bba2968f"
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+ "worksheets": [
+ {
+ "cells": [
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "### Homework 9 - Computing Periods of Stars\n",
+ "#### Kolby Weisenburger"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ " We can import %px magic cell to use use the parallel execute function. Here I am using the same code from lecture to determine the period."
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "from IPython import parallel\n",
+ "clients = parallel.Client()\n",
+ "clients.block = True # use synchronous computations\n",
+ "print(clients.ids)\n",
+ "dview = clients[:]\n",
+ "dview.block = True"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "[0, 1, 2, 3]\n"
+ ]
+ }
+ ],
+ "prompt_number": 13
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "%%px \n",
+ "import numpy as np\n",
+ "\n",
+ "from astroML.time_series import lomb_scargle\n",
+ "periods = np.logspace(-2, 0, 10000)\n",
+ "\n",
+ "def getper(id):\n",
+ " time, flux, dflux = lcs[id].T\n",
+ " periodogram = lomb_scargle(time, flux, dflux, omega=2 * np.pi / periods, generalized=True)\n",
+ " idx = np.argsort(periodogram)\n",
+ " return periods[idx[-1]]\n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [],
+ "prompt_number": 14
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "Now we can use the same .execute function that was shown in lecture. The command we would like to execute goes in the quotation marks."
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "from astroML.datasets import fetch_LINEAR_sample\n",
+ "lcs = fetch_LINEAR_sample()\n",
+ "\n",
+ "dview.scatter('ids', lcs.ids)\n",
+ "dview.execute('allper = [getper(id) for id in lcs.ids]')\n",
+ "allper = dview.gather('allper')\n",
+ "\n",
+ "print allper"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": []
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "g_r = [lcs.get_target_parameter(id, 'gr') for id in lcs.ids]"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": []
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "import matplotlib.pyplot as plt\n",
+ "%matplotlib inline\n",
+ "\n",
+ "plt.scatter(g_r, allper, alpha=0.4)\n",
+ "plt.xlabel('g-r')\n",
+ "plt.ylabel('Period')\n",
+ "plt.show()"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": []
+ }
+ ],
+ "metadata": {}
+ }
+ ]
+}