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@peko
Created October 17, 2018 22:06
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{
"cells": [
{
"cell_type": "code",
"execution_count": 2,
"metadata": {},
"outputs": [],
"source": [
"from numpy import *\n",
"from cvxpy import *"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"**Дано**\n",
"\n",
"* $n$ - ко-во складов\n",
"* $R_i$ - ко-во ресурсов на складе $i$\n",
"* $m$ - ко-во заводов\n",
"* $S_j$ - ко-во потребляемых зводом ресурсов\n",
"* $c_{i,j}$ - стоимость доставки единицы ресурса со склада $i$ на завод $j$\n",
"* $x_{i,j}$ - ко-во доставленного на завод $j$ ресурса со склада $i$\n",
"\n",
"**Нобходимо**\n",
"* Найти такие $x_{i,j}$ при которых $\\sum\\limits_{i=1}^m \\sum\\limits_{j=1}^n c_{ij} x_{ij} \\rightarrow min$"
]
},
{
"cell_type": "code",
"execution_count": 93,
"metadata": {},
"outputs": [],
"source": [
"n = 3\n",
"m = 9\n",
"R = around(random.uniform(size=n)*1000)\n",
"S = around(random.uniform(size=m)*100)+100\n",
"c = around(random.uniform(size=(n,m))*10)+1"
]
},
{
"cell_type": "code",
"execution_count": 94,
"metadata": {},
"outputs": [],
"source": [
"x = Variable((n,m), integer=True)\n",
"cond = [\n",
" x>=0,\n",
" x*ones(m)<=R,\n",
" x.T*ones(n)==S\n",
"]\n",
"obj = sum(multiply(x,c))\n",
"prob = Problem(Minimize(obj), cond)\n",
"result = prob.solve()"
]
},
{
"cell_type": "code",
"execution_count": 95,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"Минимальный расход на доставку: 5646.0\n",
"План доставки:\n",
" [[ 10. 109. -0. 0. 57. 0. -0. 0. -0.]\n",
" [ 0. -0. 149. 74. 134. 110. -0. 0. -0.]\n",
" [109. -0. -0. 92. 0. 0. 117. 101. 103.]]\n"
]
}
],
"source": [
"print(\"Минимальный расход на доставку:\",round(result))\n",
"print(\"План доставки:\\n\", around(x.value))"
]
},
{
"cell_type": "code",
"execution_count": 98,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"Потребности производства в ресурсах:\n",
" [119. 109. 149. 166. 191. 110. 117. 101. 103.]\n",
"Доставлено ресурсов на производства:\n",
" [119. 109. 149. 166. 191. 110. 117. 101. 103.]\n",
"\n",
"Начальные ресурсы на складах:\n",
" [176. 467. 722.]\n",
"Отправлено со складов:\n",
" [176. 467. 522.]\n",
"Остаток на складах:\n",
" [ 0. -0. 200.]\n"
]
}
],
"source": [
"print(\"Потребности производства в ресурсах:\\n\",S)\n",
"print(\"Доставлено ресурсов на производства:\\n\", dot(x.value.T, ones(n)))\n",
"print()\n",
"print(\"Начальные ресурсы на складах:\\n\", R)\n",
"print(\"Отправлено со складов:\\n\", around(dot(x.value, ones(m))))\n",
"print(\"Остаток на складах:\\n\", around(R-dot(x.value,ones(m))));"
]
}
],
"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": "3.6.6"
}
},
"nbformat": 4,
"nbformat_minor": 2
}
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