catalight.equipment.experiment_control.Experiment

class catalight.equipment.experiment_control.Experiment(eqpt_list=False)

Bases: object

Object containing all information necessary to run a particular experiment.

The experiment class is the center piece of catalight. This class contains several type checked properties that should be updated with relevant experimental parameters by the user. The user sets a desired experimental procedure from the list provided in expt_list

Most importantly, equipment object can be passed to each instance of Experiment and used to run the run_experiment() method to control the hardware components.

Parameters:: eqpt_list (list of objects, optional) – List of equipment objects. Calls update_eqpt_list(), if provided. Order of list should be: (GC_Connector, Diode_Laser, Gas_System, Heater)

__init__(eqpt_list=False): Init experiment object.

Methods

`__init__`([eqpt_list])	Init experiment object.
`create_dirs`(sample_path)	Create directory for storing experiment data and analysis.
`plot_sweep`([fig])	Plot the sweep parameter vs time.
`read_expt_log`(log_path)	Read data from an existing log file and update object parameters.
`run_experiment`()	Directs connected equipment to run experiment based on attributes.
`set_initial_conditions`()	Set initial conditions for experiment.
`update_date`()	Set `date` based on current date.
`update_eqpt_list`(eqpt_list)	Assign equipment objects as attributes of Experiment object.
`update_expt_log`(expt_path)	Update the experiment log based on current object parameters.
`update_save_paths`(expt_path[, should_exist])	Update data/results paths for the object.

Attributes

`data_path`	Save location for raw data, defined relative to expt_log.
`date`	Update w/ `update_date()` method.
`expt_list`	This class attr defines the possible experiments.
`expt_name`	Creates name using the fixed variables for expt
`expt_type`	Define the desired experimental procedure selected from _expt_list.
`gas_comp`	List of gas composition lists to sweep through.
`gas_type`	List of gas types for the MFCs to use to measure flow rates.
`ind_var`	Describes the variable being modified.
`power`	List of power (mW) values to step through during experiment.
`results_path`	Save location for analysis, defined relative to expt_log.
`sample_name`	Name of sample for building save paths
`sample_rate`	Sample rate in minutes (time it takes to collect a sample).
`start_time`	Updates when `set_initial_conditions()` method is called.
`temp`	List of temperature values to step through during experiment.
`tot_flow`	List of flow rates (sccm) to step through during experiment.
`sample_set_size`	Number of GC samples to collect
`t_buffer`	(min) Time between last GC sample of a step and going to next condition
`t_steady_state`	(min) Time between going to next condition and collecting first sample of a step
`heat_rate`	(deg C/min) Ramp rate to use when heating reactor.

create_dirs(sample_path)

Create directory for storing experiment data and analysis.

This function creates a set of directories to store experimental data for a given experiment and the results of the analysis. Updates the experiment name based on current expt settings and creates/updates the experiment log file in the sample path

Parameters:: sample_path (str) – Input the path where the data should be stored (sample folder)
Raises:: AttributeError – Throws error if expt_type is undefined:
Return type:: None.

property data_path

Save location for raw data, defined relative to expt_log. Update using update_save_paths()

Type:: str, read-only

property date

Update w/ update_date() method. For logging

Type:: str, read-only

property expt_list

This class attr defines the possible experiments. This is an important part of the class and should be altered with caution. Changing the units within this DF should allow different unit inputs for the rest of the codebase, but this feature is untested!!!

Type:: pandas.DataFrame, read-only

property expt_name

Creates name using the fixed variables for expt

Type:: str, read-only

property expt_type

Define the desired experimental procedure selected from _expt_list.

A key property directing much of the behavior of the class.For example, the run_experiment() method is guided by the expt_type provided. New values must be entered into the _expt_list attribute and the appropriate class methods must be edited to account for new experimental capabilities. Updates ind_var when called. Converts ‘Active Status’ in expt_list to True.

property gas_comp

List of gas composition lists to sweep through. (ex. [[gas1, gas2, gas3],[…]]) Can be len=1 if not comp sweep. Each inner list must sum to 1 or 100. Initial value of [[0.0, 50.0, 0.0, 0.0]].

Type:: list[list[float]]

property gas_type

List of gas types for the MFCs to use to measure flow rates. (ex. [gasA, gasB, gasC, …]) All values must be found in the gas library of the MFC system used. Initial value of [‘C2H2’, ‘Ar’, ‘H2’, ‘Ar’].

Type:: list[str]

heat_rate

(deg C/min) Ramp rate to use when heating reactor.

Type:: int or float

property ind_var

Describes the variable being modified. This gets updated when expt_type is updated based on what defined by expt_list.

Type:: str, read-only

plot_sweep(fig=None)

Plot the sweep parameter vs time.

Parameters:

fig (matplotlib.pyplot.figure, optional) – Can supply figure object to write plot to it. The default is None.

Returns:

matplotlib.pyplot.figure – figure object for experimental sweep. Two subplots for full and zoomed in versions. There is a hidden single subplot in background used for making shared axis titles
matplotlib.pyplot.axis – ax1 - top plot showing full experimental sweep
matplotlib.pyplot.axis – ax2 - bottom plot showing zoomed in version of experimental sweep
float – run_time - Calculate total time to run experiment

property power

List of power (mW) values to step through during experiment. One element if constant or multiple for sweep. Initial value of [0.0].

Type:: list[float]

read_expt_log(log_path)

Read data from an existing log file and update object parameters.

Grows gas_type list if more gasses are found in the expt_log than contained in current gas_type list.

Parameters:: log_path (str) – string to the full file path of the log file (‘./expt_log.txt’).
Return type:: None.

property results_path

Save location for analysis, defined relative to expt_log. Update using update_save_paths()

Type:: str, read-only

run_experiment()

Directs connected equipment to run experiment based on attributes.

Most critical method of the class/package. This method directs the equipment to actually carry out the experiment based on the assigned attribute values for the object instance. This method currently works by using a series of if-statements to determine the experiment type and take the corresponding actions.

property sample_name

Name of sample for building save paths

Type:: str

property sample_rate

Sample rate in minutes (time it takes to collect a sample).

Set sample rate based on whether GC is connected. If GC is connected, try to set sample rate to that defined by expt. If that failed, _gc_control.sample_rate will be set to min defined by ctrl file.

sample_set_size

Number of GC samples to collect

Type:: int

set_initial_conditions()

Set initial conditions for experiment.

Uses the first element of each attributes list to define initial conditions. Will also check that the temperature is not more than 10 degrees C above the first setpoint. The order is: 1. Set temperature 2. Give 1 minute time warning for laser 3. Set initial laser power 4. Set gas type 5. Set gas flows 6. Wait 2 minutes 7. Print gas flows 8. Update gc sample set size 9. Update date, time, and update log

property start_time

Updates when set_initial_conditions() method is called. For logging. Used to calculate time_passed during analysis. Given by time.time() at the end of initial conditions steps.

Type:: str, read-only

t_buffer

(min) Time between last GC sample of a step and going to next condition

Type:: int or float

t_steady_state

(min) Time between going to next condition and collecting first sample of a step

Type:: int or float

property temp

List of temperature values to step through during experiment. One element if constant or multiple for sweep. Initial value of [273.0].

Type:: list[float]

property tot_flow

List of flow rates (sccm) to step through during experiment. One element if constant or multiple for sweep. Initial value of [0.0].

Type:: list[float]

update_date(): Set date based on current date.

update_eqpt_list(eqpt_list)

Assign equipment objects as attributes of Experiment object.

Takes eqpt_list as tuple in format (gc controller, laser controller, gas controller, heater) and assigns each component to experiment object updates sample rate by given value in gc_control and updates heater ramp rate by the rate specified in experiment object

Parameters:: eqpt_list (list[object]) – (GC_Connector, Diode_Laser, Gas_System, Heater)

update_expt_log(expt_path)

Update the experiment log based on current object parameters.

Parameters:: expt_path (str) – path to the experiment folder

update_save_paths(expt_path, should_exist=True)

Update data/results paths for the object.

Used when reading expt from log file or creating new expt data set

Parameters:

expt_path (str) – string to the full file path of the experiments dir.
should_exist (bool, optional) – If updating based on existing log file, set to true. The default is True.

Raises:

ValueError – Gives error if should_exist=True and no results/data directories exists,

Return type:

None.