![\"Open](\"https://colab.research.google.com/assets/colab-badge.svg\" "\\"Open"){kind=icon}
![\"Download\"](\"https://img.shields.io/badge/Github-Download-blue.svg\" "\\"Download"){kind=icon}
"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# Zero-Order Hold and Interpolation\n",
"\n",
"Implementation of control systems generally requires an interface between the sampled data computations of process control and the continuous time dynamics of the real world. A zero-order hold is the most common model for the reconstruction of a continuous time signal from sampled data. "
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Interpolation Function"
]
},
{
"cell_type": "code",
"execution_count": 1,
"metadata": {
"collapsed": false
},
"outputs": [],
"source": [
"import numpy as np\n",
"\n",
"def interp0(x, xp, yp):\n",
" \"\"\"Zeroth order hold interpolation w/ same\n",
" (base) signature as numpy.interp.\"\"\"\n",
"\n",
" def func(x0):\n",
" if x0 <= xp[0]:\n",
" return yp[0]\n",
" if x0 >= xp[-1]:\n",
" return yp[-1]\n",
" k = 0\n",
" while x0 > xp[k]:\n",
" k += 1\n",
" return yp[k-1]\n",
" \n",
" if isinstance(x,float):\n",
" return func(x)\n",
" elif isinstance(x, list):\n",
" return [func(x) for x in x]\n",
" elif isinstance(x, np.ndarray):\n",
" return np.asarray([func(x) for x in x])\n",
" else:\n",
" raise TypeError('argument must be float, list, or ndarray')"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Demonstration"
]
},
{
"cell_type": "code",
"execution_count": 2,
"metadata": {
"collapsed": false
},
"outputs": [
{
"data": {
"text/plain": [
""
]
}
],
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