notebooks/chapter15_symbolic/03_function.ipynb

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    "> This is one of the 100 recipes of the [IPython Cookbook](http://ipython-books.github.io/), the definitive guide to high-performance scientific computing and data science in Python.\n"
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   "source": [
    "# 15.3. Analyzing real-valued functions"
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    "from sympy import *\n",
    "init_printing()"
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    "var('x z')"
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    "We define a new function depending on x."
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   "source": [
    "f = 1/(1+x**2)"
   ]
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   "source": [
    "Let's evaluate this function in 1."
   ]
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    "f.subs(x, 1)"
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    "We can compute the derivative of this function..."
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    "diff(f, x)"
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    "limits..."
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    "limit(f, x, oo)"
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    "Taylor series..."
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   "source": [
    "series(f, x0=0, n=9)"
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    "Definite integrals..."
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   "source": [
    "integrate(f, (x, -oo, oo))"
   ]
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   "source": [
    "indefinite integrals..."
   ]
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   "source": [
    "integrate(f, x)"
   ]
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   "source": [
    "and even Fourier transforms!"
   ]
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   "source": [
    "fourier_transform(f, x, z)"
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    "> You'll find all the explanations, figures, references, and much more in the book (to be released later this summer).\n",
    "\n",
    "> [IPython Cookbook](http://ipython-books.github.io/), by [Cyrille Rossant](http://cyrille.rossant.net), Packt Publishing, 2014 (500 pages)."
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