{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# 🧪 WFGY λ_diverse Demo (v0.1)\n",
    "Estimate how diverse multiple answers are for the same prompt."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Formula\n",
    "Let **A = {a₁ … aₙ}** be *n* answers.  \n",
    "λ_diverse = 1 − mean_pairwise_cosine(aᵢ, aⱼ)  \n",
    "Lower average similarity ⇒ higher diversity."
   ]
  },
  {
   "cell_type": "code",
   "metadata": { "id": "install" },
   "source": [
    "!pip -q install sentence-transformers --upgrade"
   ],
   "execution_count": null,
   "outputs": []
  },
  {
   "cell_type": "code",
   "metadata": { "id": "imports" },
   "source": [
    "from sentence_transformers import SentenceTransformer, util\n",
    "import itertools, numpy as np"
   ],
   "execution_count": null,
   "outputs": []
  },
  {
   "cell_type": "code",
   "metadata": { "id": "model" },
   "source": [
    "model = SentenceTransformer('all-MiniLM-L6-v2')"
   ],
   "execution_count": null,
   "outputs": []
  },
  {
   "cell_type": "code",
   "metadata": { "id": "helper" },
   "source": [
    "def lambda_diverse(sent_list):\n",
    "    vecs = model.encode(sent_list, convert_to_tensor=True)\n",
    "    sims = []\n",
    "    for i, j in itertools.combinations(range(len(vecs)), 2):\n",
    "        sims.append(util.cos_sim(vecs[i], vecs[j]).item())\n",
    "    return 1 - np.mean(sims)"
   ],
   "execution_count": null,
   "outputs": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## ✏️ Edit & run\n",
    "Replace the prompt + answers list, press ▶️."
   ]
  },
  {
   "cell_type": "code",
   "metadata": { "id": "user" },
   "source": [
    "prompt = \"Give me a one-sentence summary of photosynthesis.\"\n",
    "answers = [\n",
    "    \"Plants convert sunlight into chemical energy stored as sugar.\",\n",
    "    \"Using light, plants turn water and CO₂ into glucose and oxygen.\",\n",
    "    \"Through photosynthesis, green leaves make food from sunlight.\",\n",
    "    \"Plants harness solar energy to synthesize sugars from carbon dioxide.\",\n",
    "    \"Light drives the production of glucose in plants, releasing oxygen.\"\n",
    "]\n",
    "\n",
    "ld = lambda_diverse(answers)\n",
    "\n",
    "print(f\"λ_diverse : {ld:.3f}\\n\")\n",
    "if ld > 0.70:\n",
    "    label = \"High diversity ✅\"\n",
    "elif ld > 0.40:\n",
    "    label = \"Medium diversity ⚠️\"\n",
    "else:\n",
    "    label = \"Low diversity 🚨\"\n",
    "print(label)"
   ],
   "execution_count": null,
   "outputs": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "---\n",
    "### Next Steps\n",
    "* Compare diversity of *top-k* sampling vs nucleus sampling.\n",
    "* Combine with **e_resonance** to pick “diverse *and* on-topic” answers.\n"
   ]
  }
 ],
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