Replace toy_notebook_fr.ipynb

parent a489f51b
...@@ -4,15 +4,15 @@ ...@@ -4,15 +4,15 @@
"cell_type": "markdown", "cell_type": "markdown",
"metadata": {}, "metadata": {},
"source": [ "source": [
"# 1. À propos du calcul de \\( \\pi \\)\n", "# 1. À propos du calcul de $\\pi$\n",
"\n", "\n",
"## 1.1 En demandant à la lib maths\n", "## 1.1 En demandant à la lib maths\n",
"Mon ordinateur m’indique que \\( \\pi \\) vaut approximativement :" "Mon ordinateur m’indique que $\\pi$ vaut *approximativement* :"
] ]
}, },
{ {
"cell_type": "code", "cell_type": "code",
"execution_count": 15, "execution_count": 1,
"metadata": {}, "metadata": {},
"outputs": [ "outputs": [
{ {
...@@ -33,46 +33,45 @@ ...@@ -33,46 +33,45 @@
"metadata": {}, "metadata": {},
"source": [ "source": [
"## 1.2 En utilisant la méthode des aiguilles de Buffon\n", "## 1.2 En utilisant la méthode des aiguilles de Buffon\n",
"Mais calculé avec la méthode des aiguilles de Buffon, on obtiendrait comme approximation :" "Mais calculé avec la __méthode__ des [aiguilles de Buffon](https://fr.wikipedia.org/wiki/Aiguille_de_Buffon), on obtiendrait comme __approximation__ :"
] ]
}, },
{ {
"cell_type": "code", "cell_type": "code",
"execution_count": 16, "execution_count": 2,
"metadata": {}, "metadata": {},
"outputs": [ "outputs": [
{ {
"name": "stdout", "data": {
"output_type": "stream", "text/plain": [
"text": [ "3.128911138923655"
"3.128911138923655\n" ]
] },
"execution_count": 2,
"metadata": {},
"output_type": "execute_result"
} }
], ],
"source": [ "source": [
"import numpy as np\n", "import numpy as np\n",
"np.random.seed(seed=42)\n", "np.random.seed(seed=42)\n",
"\n",
"N = 10000\n", "N = 10000\n",
"x = np.random.uniform(size=N, low=0, high=1)\n", "x = np.random.uniform(size=N, low=0, high=1)\n",
"theta = np.random.uniform(size=N, low=0, high=pi/2)\n", "theta = np.random.uniform(size=N, low=0, high=pi/2)\n",
"\n", "2/(sum((x+np.sin(theta))>1)/N)"
"approx_pi = 2 / (sum((x + np.sin(theta)) > 1) / N)\n",
"print(approx_pi)"
] ]
}, },
{ {
"cell_type": "markdown", "cell_type": "markdown",
"metadata": {}, "metadata": {},
"source": [ "source": [
"## 1.3 Avec un argument fréquentiel de surface\n", "## 1.3 Avec un argument \"fréquentiel\" de surface\n",
"Une méthode plus simple à comprendre et ne faisant pas intervenir la fonction sinus se base sur le fait que si \\( X \\sim U(0,1) \\) et \\( Y \\sim U(0,1) \\), alors \\( P[X^2 + Y^2 \\leq 1] = \\pi / 4 \\).\n", "Sinon, une méthode plus simple à comprendre et ne faisant pas intervenir d'appel à la fonction sinus se base sur le fait que si $X\\sim U(0,1)$ et $Y\\sim U(0,1)$ alors $P[X^2+Y^2\\leq 1] = \\pi/4$ (voir [méthode de Monte Carlo sur Wikipedia](https://fr.wikipedia.org/wiki/M%C3%A9thode_de_Monte-Carlo#D%C3%A9termination_de_la_valeur_de_%CF%80)). Le code suivant illustre ce fait :"
"Le code suivant illustre ce fait :"
] ]
}, },
{ {
"cell_type": "code", "cell_type": "code",
"execution_count": 17, "execution_count": 3,
"metadata": {}, "metadata": {},
"outputs": [ "outputs": [
{ {
...@@ -89,49 +88,48 @@ ...@@ -89,49 +88,48 @@
} }
], ],
"source": [ "source": [
"%matplotlib inline\n", "%matplotlib inline \n",
"import matplotlib.pyplot as plt\n", "import matplotlib.pyplot as plt\n",
"\n", "\n",
"np.random.seed(seed=42)\n", "np.random.seed(seed=42)\n",
"\n",
"N = 1000\n", "N = 1000\n",
"x = np.random.uniform(size=N, low=0, high=1)\n", "x = np.random.uniform(size=N, low=0, high=1)\n",
"y = np.random.uniform(size=N, low=0, high=1)\n", "y = np.random.uniform(size=N, low=0, high=1)\n",
"\n", "\n",
"accept = (x*x + y*y) <= 1\n", "accept = (x*x+y*y) <= 1\n",
"reject = np.logical_not(accept)\n", "reject = np.logical_not(accept)\n",
"\n", "\n",
"fig, ax = plt.subplots(1)\n", "fig, ax = plt.subplots(1)\n",
"ax.scatter(x[accept], y[accept], c='b', alpha=0.2, edgecolor=None)\n", "ax.scatter(x[accept], y[accept], c='b', alpha=0.2, edgecolor=None)\n",
"ax.scatter(x[reject], y[reject], c='r', alpha=0.2, edgecolor=None)\n", "ax.scatter(x[reject], y[reject], c='r', alpha=0.2, edgecolor=None)\n",
"ax.set_aspect('equal')\n", "ax.set_aspect('equal')"
"\n",
"plt.show()"
] ]
}, },
{ {
"cell_type": "markdown", "cell_type": "markdown",
"metadata": {}, "metadata": {},
"source": [ "source": [
"Il est alors aisé d’obtenir une approximation de \\( \\pi \\) en comptant combien de fois \\( X^2 + Y^2 \\) est inférieur à 1 :" "Il est alors aisé d'obtenir une approximation (pas terrible) de $\\pi$ en comptant combien de fois, en moyenne, $X^2 + Y^2$ est inférieur à 1 :"
] ]
}, },
{ {
"cell_type": "code", "cell_type": "code",
"execution_count": 18, "execution_count": 4,
"metadata": {}, "metadata": {},
"outputs": [ "outputs": [
{ {
"name": "stdout", "data": {
"output_type": "stream", "text/plain": [
"text": [ "3.112"
"3.112\n" ]
] },
"execution_count": 4,
"metadata": {},
"output_type": "execute_result"
} }
], ],
"source": [ "source": [
"approx_pi = 4 * np.mean(accept)\n", "4*np.mean(accept)"
"print(approx_pi)"
] ]
} }
], ],
......
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