Minor copy edits

Author: jeffcarlin

DP1/300_Science_Demos/306_Extragalactic_transients/306_3_Cross_match_queries.ipynb

@@ -56,14 +56,14 @@
    "source": [
     "## 1. Introduction\n",
     "\n",
-    "This tutorial demonstrates how to make a efficient queries for the common question of \"does LSST have light curves at these sky coordinates?\" \n",
+    "This tutorial demonstrates how to make efficient queries for the common question of \"does LSST have light curves at these sky coordinates?\" \n",
     "\n",
     "**Avoid: querying the forced photometry tables by coordinate.**\n",
     "\n",
     "It is recommended that the fluxes in the forced photometry table, `ForcedSourceOnDiaObject`, be used to generate light curves.\n",
     "However, queries *by coordinate* on the `ForcedSourceOnDiaObject` table are very inefficient and should be avoided.\n",
     "This is because the `ForcedSourceOnDiaObject` table contains forced flux measurements made on every difference and direct image, at the location of every `DiaObject`.\n",
-    "It is much more efficient to do the spatial cross-match with `DiaObject` once and then retrieve forced fluxes for successful matches, rather than spatially cross-matching to the tens or hundreds (and in the future, thousands) of visits.\n",
+    "It is much more efficient to do the spatial cross-match with `DiaObject` once and then retrieve forced fluxes for successful matches based on their IDs, rather than spatially cross-matching to the tens or hundreds (and in the future, thousands) of visits.\n",
     "The same advice applies to the `ForcedSource` and `Object` tables.\n",
     "\n",
     "**Avoid: putting asynchronous queries into `for` loops.**\n",
@@ -74,7 +74,7 @@
     "**Correct: upload a table of coordinates and cross-match using a TAP table join.**\n",
     "\n",
     "This notebook demonstrates how to upload a table of coordinates and use the TAP service to cross-match\n",
-    "to the `DiaObject` table and then retrieve light curves for successfull cross-matches.\n",
+    "to the `DiaObject` table and then retrieve light curves for successful cross-matches.\n",
     "\n",
     "**Related tutorials**: The 200-level tutorials on the `DiaObject` and `ForcedSourceOnDiaObject` catalogs. The 100-level tutorials on catalog access with TAP and ADQL query statements."
    ]
@@ -218,7 +218,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "user_table"
+    "# user_table"
    ]
   },
   {
@@ -253,6 +253,7 @@
     "plt.plot(user_table['ra'][tx3], user_table['dec'][tx3], '^', ms=6, mew=0, alpha=0.7,\n",
     "         color='darkorange', label='random')\n",
     "plt.legend(loc='best', handletextpad=0)\n",
+    "plt.gca().invert_xaxis()\n",
     "plt.xlabel('RA')\n",
     "plt.ylabel('Dec')\n",
     "plt.show()"