def thermocycle_ramp(start_temp, end_temp, total_duration, step_duration):
"""Create a ramp instruction for the thermocyler.
Create a multi-temperature thermocycling program commonly used in
annealing protocols. Based on total time and the step duration this
function computes the temperature increment required for each step within
the start and the end temperature.
Parameters
----------
start_temp: string, int, float, Unit
Start of the thermocycle protocol, in the format "37:celsius"
end_temp: string, int, float, Unit
End of the thermocycle protocol, in the format "37:celsius"
total_duration: string, Unit
Total duration of the thermocycle protocol, in the format "1:hour"
step_duration: string, Unit
Time that each temperature should be held, in the format "1:minute"
Example
-------
.. code-block:: python
therm = thermocycle_ramp(65, 95, "30:minute", "1:minute")
protocol.thermocycle(dest_plate,
therm,
volume="15:microliter")
Returns
-------
dict
containing thermocycling steps that can be used in the
thermocycle instruction
Raises
------
ValueError
If either temperature is not of type `int`, `float`, `string` or
`Unit` and if either duration is not of type `string` or `Unit`
"""
assert isinstance(start_temp, (int, float, string_type, Unit))
assert isinstance(end_temp, (int, float, string_type, Unit))
assert isinstance(total_duration, (string_type, Unit))
assert isinstance(step_duration, (string_type, Unit))
if isinstance(start_temp, string_type):
start_temp = Unit.fromstring(start_temp)
elif isinstance(start_temp, (int, float)):
start_temp = Unit(start_temp, 'degC')
if isinstance(end_temp, string_type):
end_temp = Unit.fromstring(end_temp)
elif isinstance(end_temp, (int, float)):
end_temp = Unit(end_temp, 'degC')
if isinstance(total_duration, string_type):
total_duration = Unit.fromstring(total_duration)
if isinstance(step_duration, string_type):
step_duration = Unit.fromstring(step_duration)
start_temp.ito('degC')
end_temp.ito('degC')
total_duration.ito_base_units()
step_duration.ito_base_units()
num_steps = int(total_duration // step_duration)
step_size = (end_temp - start_temp).magnitude // num_steps
thermocycle_steps = []
for i in range(num_steps + 1):
thermocycle_steps.append({
"temperature": "%s:celsius" % (
start_temp.magnitude + i * step_size),
"duration": str(step_duration)
})
return thermocycle_steps
