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   "source": [
    "# Sending data to Python \n",
    "\n",
    "```{admonition} Interactive page\n",
    ":class: warning, dropdown\n",
    "This is an interactive book page. Press the launch button at the top right side.\n",
    "```\n",
    "\n",
    "So far we have seen examples of **output**, i.e., Python telling us things like in the \"Hello world\" example. \n",
    "We have also seen examples of **code**, i.e., us giving instructions to Python in order for it to do things. \n",
    "\n",
    "In addition, we can also **send data to Python**. Often in science, we do this by having Python read data files (more on this in a [later chapter](../chapter9/data-files.ipynb)), but we can also send information to Python using `input()`:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "tags": [
     "remove-output"
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   "outputs": [],
   "source": [
    "a = input()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "You can specify text for the label of the input box to clarify what kind of input you expect from the user:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "tags": [
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   "source": [
    "a = input(\"Enter a number:\")"
   ]
  },
  {
   "cell_type": "markdown",
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   "source": [
    "Even if we type a number into the input box, it will **always return a variable of type string** `str`. If we want to subsequently use our input as a number, we have to **explicitly convert** it to a number (remember: which property of Python causes this?). For example, we can use the `float()` function:\n",
    "\n",
    "```\n",
    "a = input()\n",
    "a = float(a)\n",
    "print(\"The value of a is:\", a)\n",
    "print(\"a has the type:\", type(a))\n",
    "```\n",
    "\n",
    "Because `input` is buggy in the current version of the Jupyter book, try out this code in your local installation of VS Code.\n",
    "\n",
    "```{exercise}\n",
    ":class: dropdown\n",
    "Use the `input` function to get parameters of integer, float, and string types into the program. Do this in VS Code.\n",
    "```"
   ]
  }
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