adding NB demo for roman ramps in cubeviz

notebooks/concepts/cubeviz-roman-ramp.ipynb

@@ -0,0 +1,80 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "b3e22694-d8ee-4c14-8931-8f8db1d7485d",
+   "metadata": {
+    "tags": []
+   },
+   "source": [
+    "## PoC: Visualize a Roman L1 ramp file in Cubeviz\n",
+    "\n",
+    "First download a synthetic Roman L1 file:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "e80524dd-bcc5-4312-879a-33780e297006",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [],
+   "source": [
+    "import os\n",
+    "from urllib.request import urlretrieve\n",
+    "\n",
+    "url_L1 = \"https://stsci.box.com/shared/static/24gpvqb9676acdy6hjvymc2llgcny8ul.asdf\"\n",
+    "local_path = \"L1.asdf\"\n",
+    "\n",
+    "if not os.path.exists(local_path):\n",
+    "    urlretrieve(url_L1, local_path)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "0f94fbf1-6f4c-4118-917d-de824af57fe6",
+   "metadata": {},
+   "source": [
+    "Open the ramp in Cubeviz:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "863ce611-bf38-4a97-bd1d-c0ff79d36073",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [],
+   "source": [
+    "from jdaviz import Cubeviz\n",
+    "\n",
+    "cubeviz = Cubeviz()\n",
+    "cubeviz.load_data(local_path, data_label='Roman L1')\n",
+    "cubeviz.show(height=1000)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "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": "3.11.4"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}