{
"cells": [
{
"cell_type": "code",
"execution_count": 1,
"metadata": {},
"outputs": [],
"source": [
"import os\n",
"import sys\n",
"sys.path.append(os.path.abspath(os.path.join('..')))\n",
"from ch07_autograd.utils import Scalar, draw_graph"
]
},
{
"cell_type": "code",
"execution_count": 2,
"metadata": {},
"outputs": [],
"source": [
"def scalar_sum(nums):\n",
" \"\"\"\n",
" 为了作图美观,定义基于Scalar的求和运算\n",
" \"\"\"\n",
" value = 0.0\n",
" requires_grad = False\n",
" wrt = {}\n",
" for item in nums:\n",
" value += item.value\n",
" wrt[item] = 1.0\n",
" requires_grad = requires_grad or item.requires_grad\n",
" output = Scalar(value, nums, 'sum')\n",
" output.requires_grad=requires_grad\n",
" output.grad_wrt = wrt\n",
" return output"
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {},
"outputs": [
{
"data": {
"image/svg+xml": [
"\n",
"\n",
"\n",
"\n",
"\n"
],
"text/plain": [
""
]
},
"execution_count": 3,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"w1 = Scalar(1.0, label='w1')\n",
"w2 = Scalar(2.0, label='w2')\n",
"w3 = Scalar(3.0, label='w3')\n",
"b = Scalar(4.0, label='b')\n",
"x1 = Scalar(1.1, label='x1', requires_grad=False)\n",
"x2 = Scalar(2.1, label='x2', requires_grad=False)\n",
"x3 = Scalar(3.1, label='x3', requires_grad=False)\n",
"h = scalar_sum([w1 * x1, w2 * x2, w3 * x3, b])\n",
"y = h.sigmoid()\n",
"draw_graph(y)"
]
}
],
"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": "3.8.5"
}
},
"nbformat": 4,
"nbformat_minor": 4
}