Impl: support for Square Wave Voltammetry experiments

.coveragerc

@@ -5,7 +5,7 @@ source =
 
 omit = 
     gamry_parser/__init__.py
-    gamry_praser/version.py
+    gamry_parser/version.py
 
 [report]
 exclude_lines =

CHANGELOG.md

@@ -13,13 +13,24 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 ### Added
 - 
 
+## [0.4.6] - 2021-05-07
+
+### Fixed
+- [ed0c932](https://github.com/bcliang/gamry-parser/commit/ed0c93208f5a5ce3b62d5c619e3fd6aa34158b35) Fix: Static typing for class methods, resolve pandas futurewarning
+
+### Changed
+- 
+
+### Added
+- [#45](https://github.com/bcliang/gamry-parser/pull/45) Impl: support for Square Wave Voltammetry experiments
+
 ## [0.4.5] - 2021-05-07
 
 ### Fixed
 - 
 
 ### Changed
-- [#40](https://github.com/bcliang/gamry-parser/pull/40) Change: GamryParser to_timestamp param #40
+- [#40](https://github.com/bcliang/gamry-parser/pull/40) Change: GamryParser to_timestamp param
 - [#41](https://github.com/bcliang/gamry-parser/pull/41) Use tox as test runner
 
 ### Added

README.md

@@ -77,10 +77,16 @@ print(ca.get_curve_data())
 
 #### Demos
 
+A simple demonstration is provided in `usage.py`. 
+
+`python usage.py` 
+
 ipython notebook demonstration scripts are included in the `demo` folder.
 
 - `notebook_gamry_parser.ipynb`: Simple example loading data from ChronoA experiment output. Instead of `gamry_parser.GamryParser()`, the parser could be instantiated with `gamry_parser.ChronoAmperometry()`
 - `notebook_cyclicvoltammetry.ipynb`: Example loading data from a CV (cyclic voltammetry) experiment output. Uses the `gamry_parser.CyclicVoltammetry()` subclass.
+- `notebook_cyclicvoltammetry_peakdetect.ipynb`: Another example that demonstrates loading CV data and detecting peaks in the data using `scipy.signal.find_peaks()`
+- `notebook_potentiostatic_eis.ipynb`: Example loading data from an EIS (electrochemical impedance spectroscopy) experiment. Uses the `gamry_parser.Impedance()` subclass.
 
 #### Additional Examples
 

gamry_parser/__init__.py

@@ -4,4 +4,5 @@
 from .cv import CyclicVoltammetry
 from .eispot import Impedance
 from .ocp import OpenCircuitPotential
+from .squarewave import SquareWaveVoltammetry
 from .vfp600 import VFP600

gamry_parser/gamryparser.py

@@ -9,10 +9,23 @@
 class GamryParser:
     """Load experiment data generated in Gamry EXPLAIN format."""
 
-    fname = None
-    to_timestamp = False
+    fname: str = None
+    to_timestamp: bool = False
+    loaded: bool = False
 
-    def __init__(self, filename=None, to_timestamp=None):
+    header_length: int = 0
+    header: dict = None
+
+    curve_count: int = 0
+    curves: list = []
+    curve_units: dict = dict()
+
+    ocv_exists: bool = False
+    ocv: pd.DataFrame = None
+
+    REQUIRED_UNITS: dict = dict(CV=dict(Vf="V vs. Ref.", Im="A"))
+
+    def __init__(self, filename: str = None, to_timestamp: bool = None):
         """GamryParser.__init__
 
         Args:
@@ -27,17 +40,22 @@ def __init__(self, filename=None, to_timestamp=None):
         self.to_timestamp = (
             to_timestamp if to_timestamp is not None else self.to_timestamp
         )
+        self._reset_props()
+
+    def _reset_props(self):
+        "re-initialize parser properties"
+
+        self.loaded = False
+
         self.header = dict()
         self.header_length = 0
-        self.loaded = False
+
         self.curves = []
         self.curve_count = 0
         self.curve_units = dict()
-        self.ocv = None
+
         self.ocv_exists = False
-        self.REQUIRED_UNITS = {
-            "CV": {"Vf": "V vs. Ref.", "Im": "A"},
-        }
+        self.ocv = None
 
     def load(self, filename: str = None, to_timestamp: bool = None):
         """save experiment information to \"header\", then save curve data to \"curves\"
@@ -81,22 +99,22 @@ def _convert_T_to_Timestamp(self):
         for curve in self.curves:
             curve["T"] = start_time + pd.to_timedelta(curve["T"], "s")
 
-    def get_curve_count(self):
+    def get_curve_count(self) -> int:
         """return the number of loaded curves"""
         assert self.loaded, "DTA file not loaded. Run GamryParser.load()"
         return self.curve_count
 
-    def get_curve_indices(self):
+    def get_curve_indices(self) -> tuple:
         """return indices of curves (zero-based indexing)"""
         assert self.loaded, "DTA file not loaded. Run GamryParser.load()"
         return tuple(range(self.curve_count))
 
-    def get_curve_numbers(self):
+    def get_curve_numbers(self) -> tuple:
         """return Gamry curve numbers (one-based indexing, as in Gamry software)"""
         assert self.loaded, "DTA file not loaded. Run GamryParser.load()"
         return tuple(range(1, self.curve_count + 1))
 
-    def get_curve_data(self, curve: int = 0):
+    def get_curve_data(self, curve: int = 0) -> pd.DataFrame:
         """retrieve relevant experimental data
 
         Args:
@@ -114,17 +132,17 @@ def get_curve_data(self, curve: int = 0):
         )
         return self.curves[curve]
 
-    def get_curves(self):
+    def get_curves(self) -> list:
         """return all loaded curves as a list of pandas DataFrames"""
         assert self.loaded, "DTA file not loaded. Run GamryParser.load()"
         return self.curves
 
-    def get_header(self):
+    def get_header(self) -> list:
         """return the experiment configuration dictionary"""
         assert self.loaded, "DTA file not loaded. Run GamryParser.load()"
         return self.header
 
-    def get_experiment_type(self):
+    def get_experiment_type(self) -> str:
         """retrieve the type of experiment that was loaded (TAG)
 
         Args:
@@ -136,7 +154,7 @@ def get_experiment_type(self):
         assert self.loaded, "DTA file not loaded. Run GamryParser.load()"
         return self.header["TAG"]
 
-    def get_ocv_curve(self):
+    def get_ocv_curve(self) -> pd.DataFrame:
         """return the contents of OCVCURVE (if it exists). Deprecated in Framework version 7"""
         if self.ocv_exists:
             return self.ocv
@@ -150,7 +168,7 @@ def get_ocv_value(self):
         else:
             return None
 
-    def read_header(self):
+    def read_header(self) -> list:
         """helper function to grab data from the EXPLAIN file header, which contains the loaded experiment's configuration
 
         Args:
@@ -216,7 +234,7 @@ def read_header(self):
 
         return self.header, self.header_length
 
-    def read_curve_data(self, fid: int):
+    def read_curve_data(self, fid: int) -> tuple:
         """helper function to process an EXPLAIN Table
 
         Args:
@@ -247,7 +265,7 @@ def read_curve_data(self, fid: int):
 
         return keys, units, curve
 
-    def read_curves(self):
+    def read_curves(self) -> list:
         """helper function to iterate through curves in a dta file and save as individual dataframes
 
         Args:

gamry_parser/squarewave.py

@@ -0,0 +1,74 @@
+import gamry_parser as parser
+
+
+class SquareWaveVoltammetry(parser.GamryParser):
+    """Load a Square Wave Voltammetry (SWV) experiment generated in Gamry EXPLAIN format."""
+
+    def load(self, filename: str = None, to_timestamp: bool = None):
+        """save experiment information to \"header\", then save curve data to \"curves\"
+
+        Args:
+            filename (str, optional): file containing VFP600 data. defaults to None.
+        Returns:
+            None
+
+        """
+        super(SquareWaveVoltammetry, self).load(
+            filename=filename, to_timestamp=to_timestamp
+        )
+        typecheck = self.header.get("TAG", None)
+        assert (
+            typecheck == "SQUARE_WAVE"
+        ), f"The input file does not contain data from a square wave voltammetry experiment (expected type SQUARE_WAVE, found {typecheck})."
+
+    @property
+    def step_size(self):
+        return self.header.get("STEPSIZE", None)
+
+    @property
+    def pulse_size(self):
+        return self.header.get("PULSESIZE", None)
+
+    @property
+    def pulse_width(self):
+        return self.header.get("PULSEON", None)
+
+    @property
+    def frequency(self):
+        return self.header.get("FREQUENCY", None)
+
+    @property
+    def v_range(self):
+        return (self.header.get("VINIT", 0), self.header.get("VFINAL", 0))
+
+    @property
+    def cycles(self):
+        return self.header.get("CYCLES", 0)
+
+    def get_curve_data(self, curve: int = 0):
+        """retrieve relevant SWV experimental data
+
+        Args:
+            curve (int, optional): curve number to return. Defaults to 0.
+
+        Returns:
+            pandas.DataFrame:
+                - T: time, in seconds or Timestamp
+                - Vfwd: forward potential, in V
+                - Vrev: reverse potential, in V
+                - Vstep: step potential, in V
+                - Ifwd: peak forward current measurement, in A
+                - Irev: peak reverse current measurement, in A
+                - Idif: differential current measurement (pulse), in A
+
+        """
+        assert self.loaded, "DTA file not loaded. Run CyclicVoltammetry.load()"
+        assert curve >= 0, "Invalid curve ({}). Indexing starts at 0".format(curve)
+        assert (
+            curve < self.curve_count
+        ), "Invalid curve ({}). File contains {} total curves.".format(
+            curve, self.curve_count
+        )
+        df = self.curves[curve]
+
+        return df[["T", "Vfwd", "Vrev", "Vstep", "Ifwd", "Irev", "Idif"]]

gamry_parser/version.py

@@ -1 +1 @@
-__version__ = "0.4.5"
+__version__ = "0.4.6"

tests/squarewave_data.dta

@@ -0,0 +1,76 @@
+EXPLAIN
+TAG	SQUARE_WAVE
+TITLE	LABEL	test-square-wave-experiment	Test &Identifier
+DATE	LABEL	12/31/2021	Date
+TIME	LABEL	12:00:00	Time
+PSTAT	PSTAT	REF600-10000	Potentiostat
+NOTES	NOTES	1	&Notes...
+
+VINIT	QUANT	0.00000E+000	Initial &E (V)
+VFINAL	QUANT	-5.00000E-001	Final &E (V)
+STEPSIZE	QUANT	2.00000E+000	St&ep Size (mV)
+TIMERRES	QUANT	3.33340E-005	&Timer Resolution
+FREQUENCY	QUANT	1.00000E+002	&Frequency (Hz)
+PULSESIZE	QUANT	2.50000E+001	Pulse Size &Epeak (mV)
+PULSEON	QUANT	1.00000E-002	Pulse &Time (s)
+AREA	QUANT	1.00000E+000	Electrode &Area (cm^2)
+IMODE	SELECTOR	1	I/E Range &Mode
+IRANGE	QUANT	1.00000E-002	&Max Current (mA)
+EQDELAY	IQUANT	0	Equil. &Time (s)
+IRCOMP	SELECTOR	0	IRCom&p
+PFCOR	QUANT	5.00000E+001	PF Corr. (ohm)
+CYCLES	IQUANT	251	C&ycles (#)
+ELECTRODETYPE	SELECTOR	0	Electrode Type
+STRIPPING	TOGGLE	F	Used for Stripping
+POLARITY	TOGGLE	F	Signal Polarity
+LINEFREQ	IQUANT	60	Line Frequency (Hz)
+SAMPLINGMODE	SELECTOR	0	Sampling &Mode
+PSTATMODEL	IQUANT	4	Pstat Model
+PSTATSECTION	LABEL	REF600-19054	Pstat Section
+PSTATSERIALNO	LABEL	19054	Pstat Serial Number
+CTRLMODE	IQUANT	1	Control Mode
+ELECTROMETER	IQUANT	0	RE=0 or CS=1
+IESTAB	IQUANT	2	I/E Stability
+CASPEED	IQUANT	6	Control Amp Speed
+CONVENTION	IQUANT	0	Current Convention
+ICHRANGE	IQUANT	2	Ich Range
+ICHRANGEMODE	TOGGLE	F	Ich Auto Range
+ICHOFFSETENABLE	TOGGLE	F	Ich Offset Enable
+ICHOFFSET	QUANT	0	Ich Offset (V)
+ICHFILTER	IQUANT	2	Ich Filter
+VCHRANGE	IQUANT	2	Vch Range
+VCHRANGEMODE	TOGGLE	F	Vch Auto Range
+VCHOFFSETENABLE	TOGGLE	F	Vch Offset Enable
+VCHOFFSET	QUANT	0	Vch Offset (V)
+VCHFILTER	IQUANT	1	Vch Filter
+ACHRANGE	IQUANT	2	Ach Range
+ACHOFFSETENABLE	TOGGLE	F	Ach Offset Enable
+ACHOFFSET	QUANT	0	Ach Offset (V)
+ACHFILTER	IQUANT	1	Ach Filter
+IERANGELOWERLIMIT	IQUANT	1	I/E Range Lower Limit
+IERANGEMODE	TOGGLE	F	I/E AutoRange
+IERANGE	IQUANT	7	I/E Range
+POSFEEDENABLE	TOGGLE	F	Positive Feedback IR Comp
+POSFEEDRESISTANCE	QUANT	0	Positive Feedback Resistance (ohm)
+ACHSELECT	IQUANT	4	Ach Select
+SENSECABLEID	IQUANT	14	Sense Cable ID
+PWRCABLEID	IQUANT	14	Power Cable ID
+DCCALDATE	LABEL	9/10/2021	DC Calibration Date
+ACCALDATE	LABEL	3/30/2021	AC Calibration Date
+THERMOSELECT	IQUANT	1	Thermo Select
+FRAMEWORKVERSION	LABEL	7.8.4	Framework Version
+INSTRUMENTVERSION	LABEL	4.42	Instrument Version
+CURVE	TABLE	251
+	Pt	T	Vfwd	Vrev	Vstep	Ifwd	Irev	Idif	Sig	Ach	IERange	Over	Temp
+	#	s	V	V	V	A	A	A	V	V	#	bits	deg C
+	0	0.01	-2.55258E-002	3.75742E-002	6.02416E-003	1.95523E-007	-1.73274E-006	1.92826E-006	2.50000E-002	5.08394E-005	7	...........	-0.01
+	1	0.02	-4.32258E-002	3.87742E-002	-2.22584E-003	8.75084E-008	-3.26548E-007	4.14056E-007	2.30000E-002	8.39387E-007	7	...........	-0.01
+	2	0.03	-4.59258E-002	3.68742E-002	-4.52584E-003	-3.20547E-007	-8.85156E-008	-2.32032E-007	2.10000E-002	5.08394E-005	7	...........	-0.01
+	3	0.04	-4.79258E-002	3.48742E-002	-6.52584E-003	-3.20547E-007	-4.65099E-008	-2.74037E-007	1.90000E-002	8.39387E-007	7	...........	-0.01
+	4	0.05	-5.01258E-002	3.28742E-002	-8.62584E-003	-3.28548E-007	-4.50415E-009	-3.24044E-007	1.70000E-002	8.39387E-007	7	...........	-0.01
+	5	0.06	-5.21258E-002	3.07742E-002	-1.06758E-002	-3.16547E-007	-1.45055E-008	-3.02041E-007	1.50000E-002	8.39387E-007	7	...........	-0.01
+	6	0.07	-5.41258E-002	2.90742E-002	-1.25258E-002	-2.96544E-007	2.14994E-008	-3.18043E-007	1.30000E-002	8.39387E-007	7	...........	-0.01
+	7	0.08	-5.59258E-002	2.66742E-002	-1.46258E-002	-3.28548E-007	3.75016E-008	-3.66050E-007	1.10000E-002	-4.91606E-005	7	...........	-0.01
+	8	0.09	-5.79258E-002	2.46742E-002	-1.66258E-002	-3.08546E-007	3.95018E-008	-3.48047E-007	9.00000E-003	-4.91606E-005	7	...........	-0.01
+	9	0.1	-6.00258E-002	2.26742E-002	-1.86758E-002	-3.34549E-007	6.75057E-008	-4.02055E-007	7.00000E-003	8.39387E-007	7	...........	-0.01
+EXPERIMENTABORTED	TOGGLE	T	Experiment Aborted