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   "source": [
    "# ScaledParameter\n",
    "Sometimes the values that we set/get on the computer are not the physical value that reach/originate from the sample. The ScaledParameter can be used to convert quantities with a simple linear relationship without offset."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "from qcodes.parameters import ManualParameter, ScaledParameter"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "dac0 = ManualParameter('dac0', unit = 'V')\n",
    "dac1 = ManualParameter('dac1', unit = 'V')\n",
    "amplitude = ManualParameter('amplitude', initial_value=3.14, unit = 'V')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Resistive voltage divider\n",
    "The simplest case is a resistive divider, where the set voltage is divided by a fixed amount."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [],
   "source": [
    "vd = ScaledParameter(dac0, division = 10)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [],
   "source": [
    "vd(10)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Vd = 10.0 V , real setted value = 100 V\n"
     ]
    }
   ],
   "source": [
    "print('Vd =',vd(), vd.unit,', real setted value =', dac0(), dac0.unit)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Voltage multiplier\n",
    "If the voltage is amplified, we can specify a `gain` value instead of `division`."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [],
   "source": [
    "vb = ScaledParameter(dac1, gain = 30, name = 'Vb')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [],
   "source": [
    "vb(5)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Vb = 10.0 V , Original_value = 0.16666666666666666 V\n"
     ]
    }
   ],
   "source": [
    "print('Vb =',vd(), vb.unit,', Original_value =', dac1(), dac1.unit)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Transimpedance amplifier\n",
    "The ScaledParameter can be used also for quantities that are read, like a current read by a transimpedance amplifier, digitized by a multimeter.\n",
    "We can also specify a different unit from the wrapped parameter. The semantic of gain/division is inverted compared to the previous cases, since it is a value that we read."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [],
   "source": [
    "Id = ScaledParameter(amplitude, division = 1e6, name = 'Id', unit = 'A')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Id = 3.14e-06 A , Read_value = 3.14 V\n"
     ]
    }
   ],
   "source": [
    "print('Id =',Id(), Id.unit,', Read_value =', amplitude(), amplitude.unit)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "The gain can be manually changed at any time"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Id = 3.14e-08 A , Read_value = 3.14 V\n"
     ]
    }
   ],
   "source": [
    "Id.division = 1e8\n",
    "print('Id =',Id(), Id.unit,', Read_value =', amplitude(), amplitude.unit)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "The gain/division can be itself a Qcodes paramter, for example if is a gain set by a remote instrument"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [],
   "source": [
    "remote_gain = ManualParameter('remote_gain', initial_value=1e6, unit = 'V/A')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Id = 3.14e-06 A , Read_value = 3.14 V\n"
     ]
    }
   ],
   "source": [
    "Id.division = remote_gain\n",
    "print('Id =',Id(), Id.unit,', Read_value =', amplitude(), amplitude.unit)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Id = 3.14e-08 A , Read_value = 3.14 V\n"
     ]
    }
   ],
   "source": [
    "remote_gain(1e8)\n",
    "print('Id =',Id(), Id.unit,', Read_value =', amplitude(), amplitude.unit)"
   ]
  }
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