#!/usr/bin/env python
# coding: utf-8

# # ScaledParameter
# 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.

# In[1]:


from qcodes import ManualParameter, ScaledParameter


# In[2]:


dac0 = ManualParameter('dac0', unit = 'V')
dac1 = ManualParameter('dac1', unit = 'V')
amplitude = ManualParameter('amplitude', initial_value=3.14, unit = 'V')


# ## Resistive voltage divider
# The simplest case is a resistive divider, where the set voltage is divided by a fixed amount.

# In[6]:


vd = ScaledParameter(dac0, division = 10)


# In[7]:


vd(10)


# In[8]:


print('Vd =',vd(), vd.unit,', real setted value =', dac0(), dac0.unit)


# ## Voltage multiplier
# If the voltage is amplified, we can specify a `gain` value instead of `division`.

# In[6]:


vb = ScaledParameter(dac1, gain = 30, name = 'Vb')


# In[7]:


vb(5)


# In[8]:


print('Vb =',vd(), vb.unit,', Original_value =', dac1(), dac1.unit)


# ## Transimpedance amplifier
# The ScaledParameter can be used also for quantities that are read, like a current read by a transimpedance amplifier, digitized by a multimeter.
# 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.

# In[9]:


Id = ScaledParameter(amplitude, division = 1e6, name = 'Id', unit = 'A')


# In[10]:


print('Id =',Id(), Id.unit,', Read_value =', amplitude(), amplitude.unit)


# The gain can be manually changed at any time

# In[11]:


Id.division = 1e8
print('Id =',Id(), Id.unit,', Read_value =', amplitude(), amplitude.unit)


# The gain/division can be itself a Qcodes paramter, for example if is a gain set by a remote instrument

# In[12]:


remote_gain = ManualParameter('remote_gain', initial_value=1e6, unit = 'V/A')


# In[13]:


Id.division = remote_gain
print('Id =',Id(), Id.unit,', Read_value =', amplitude(), amplitude.unit)


# In[14]:


remote_gain(1e8)
print('Id =',Id(), Id.unit,', Read_value =', amplitude(), amplitude.unit)