def __init__(self): super().__init__({ "coherence": Range(50, 100), "presample": Natural0, "highreward": Set([0, 1]), "blocktype": Set([1, 2]) })
class Solution(object): """Describes the result of an analytic or numerical DDM run. This is a glorified container for a joint pdf, between the response options (correct, error, and undecided) and the response time distribution associated with each. It stores a copy of the response time distribution for both the correct case and the incorrect case, and the rest of the properties can be calculated from there. It also stores a full deep copy of the model used to simulate it. This is most important for storing, e.g. the dt and the name associated with the simulation, but it is also good to keep the whole object as a full record describing the simulation, so that the full parametrization of every run is recorded. Note that this may increase memory requirements when many simulations are run. """ @staticmethod def _test(v): # TODO should these be Positive0 instead of Number? assert v.corr in NDArray(d=1, t=Number), "Invalid corr histogram" assert v.err in NDArray(d=1, t=Number), "Invalid err histogram" if v.undec is not None: assert v.undec in NDArray(d=1, t=Number), "Invalid err histogram" assert len(v.undec) == len( v.model.x_domain(conditions=v.conditions)) #assert v.model is Generic(Model), "Invalid model" # TODO could cause inf recursion issue assert len(v.corr) == len(v.err) == len( v.model.t_domain()), "Histogram lengths must match" assert 0 <= fsum(v.corr.tolist() + v.err.tolist()) <= 1, "Histogram does not integrate " \ " to 1, not to " + str(fsum(v.corr.tolist() + v.err.tolist())) assert v.conditions in Conditions() @staticmethod def _generate(): from .model import Model # Importing here avoids a recursion issue m = Model() T = m.t_domain() lT = len(T) X = m.x_domain(conditions={}) lX = len(X) # All undecided yield Solution(np.zeros(lT), np.zeros(lT), m, next(Conditions().generate())) # Uniform yield Solution( np.ones(lT) / (2 * lT), np.ones(lT) / (2 * lT), m, next(Conditions().generate())) # With uniform undecided probability yield Solution(np.ones(lT) / (3 * lT), np.ones(lT) / (3 * lT), m, next(Conditions().generate()), pdf_undec=np.ones(lX) / (3 * lX)) # With uniform undecided probability with collapsing bounds from .models.bound import BoundCollapsingExponential m2 = Model(bound=BoundCollapsingExponential(B=1, tau=1)) T2 = m2.t_domain() lT2 = len(T2) X2 = m2.x_domain(conditions={}) lX2 = len(X2) yield Solution(np.ones(lT2) / (3 * lT2), np.ones(lT2) / (3 * lT2), m2, next(Conditions().generate()), pdf_undec=np.ones(lX2) / (3 * lX2)) def __init__(self, pdf_corr, pdf_err, model, conditions, pdf_undec=None): """Create a Solution object from the results of a model simulation. Constructor takes four arguments. - `pdf_corr` - a size N numpy ndarray describing the correct portion of the joint pdf - `pdf_err` - a size N numpy ndarray describing the error portion of the joint pdf - `model` - the Model object used to generate `pdf_corr` and `pdf_err` - `conditions` - a dictionary of condition names/values used to generate the solution - `pdf_undec` - a size M numpy ndarray describing the final state of the simulation. None if unavailable. """ self.model = copy.deepcopy( model ) # TODO this could cause a memory leak if I forget it is there... self.corr = pdf_corr self.err = pdf_err self.undec = pdf_undec # Correct floating point errors to always get prob <= 1 if fsum(self.corr.tolist() + self.err.tolist()) > 1: self.corr /= 1.00000000001 self.err /= 1.00000000001 self.conditions = conditions def __eq__(self, other): if not np.allclose(self.corr, other.corr) or \ not np.allclose(self.err, other.err): return False for k in self.conditions: if k not in other.conditions: return False if np.issubdtype(self.conditions[k][0].dtype, np.floating) and \ np.issubdtype(self.conditions[k][0].dtype, np.floating): compare_func = np.allclose else: compare_func = lambda x, y: np.all(np.equal(x, y)) if not compare_func(self.conditions[k][0], other.conditions[k][0]) or \ not compare_func(self.conditions[k][1], other.conditions[k][1]): return False if len(self.conditions[k]) == 3 and \ len(other.conditions[k]) == 3 and \ not compare_func(self.conditions[k][2], other.conditions[k][2]): return False if self.undec is not None: if not np.allclose(self.undec, other.undec): return False return True @accepts(Self) @returns(NDArray(d=1, t=Positive0)) def pdf_corr(self): """The correct component of the joint PDF.""" return self.corr / self.model.dt @accepts(Self) @returns(NDArray(d=1, t=Positive0)) def pdf_err(self): """The error (incorrect) component of the joint PDF.""" return self.err / self.model.dt @accepts(Self) @returns(NDArray(d=1, t=Positive0)) @requires("self.undec is not None") def pdf_undec(self): """The final state of the simulation, same size as `x_domain()`. If the model contains overlays, this represents the final state of the simulation *before* the overlays are applied. This is because overlays do not specify what to do with the diffusion locations corresponding to undercided probabilities. Additionally, all of the necessary information may not be stored, such as the case with a non-decision time overlay. This means that in the case of models with a non-decision time t_nd, this gives the undecided probability at time T_dur + t_nd. If no overlays are in the model, then pdf_corr() + pdf_err() + pdf_undec() should always equal 1 (plus or minus floating point errors). """ # Do this here to avoid import recursion from .models.overlay import OverlayNone # Common mistake so we want to warn the user of any possible # misunderstanding. if not isinstance(self.model.get_dependence("overlay"), OverlayNone): print( "WARNING: Undecided probability accessed for model with overlays. " "Undecided probability applies *before* overlays. Please see the " "pdf_undec docs for more information and to prevent misunderstanding." ) if self.undec is not None: return self.undec / self.model.dx else: raise ValueError("Final state unavailable") @accepts(Self) @returns(NDArray(d=1, t=Positive0)) def cdf_corr(self): """The correct component of the joint CDF.""" return np.cumsum(self.corr) @accepts(Self) @returns(NDArray(d=1, t=Positive0)) def cdf_err(self): """The error (incorrect) component of the joint CDF.""" return np.cumsum(self.err) @accepts(Self) @returns(Range(0, 1)) def prob_correct(self): """Probability of correct response within the time limit.""" return fsum(self.corr) @accepts(Self) @returns(Range(0, 1)) def prob_error(self): """Probability of incorrect (error) response within the time limit.""" return fsum(self.err) @accepts(Self) @returns(Range(0, 1)) def prob_undecided(self): """The probability of not responding during the time limit.""" udprob = 1 - fsum(self.corr.tolist() + self.err.tolist()) if udprob < 0: print("Warning, setting undecided probability from %f to 0" % udprob) udprob = 0 return udprob @accepts(Self) @returns(Range(0, 1)) def prob_correct_forced(self): """Probability of correct response if a response is forced. Forced responses are selected randomly.""" return self.prob_correct() + self.prob_undecided() / 2. @accepts(Self) @returns(Range(0, 1)) def prob_error_forced(self): """Probability of incorrect response if a response is forced. Forced responses are selected randomly.""" return self.prob_error() + self.prob_undecided() / 2. @accepts(Self) @returns(Range(0, 1)) @requires("self.undec is not None") def prob_correct_sign(self): """Probability of correct response if a response is forced. Forced responses are selected by the position of the decision variable at the end of the time limit T_dur. This is only available for the implicit method. """ return self.prob_correct() + np.sum( self.undec[len(self.undec) // 2 + 1:]) @accepts(Self) @returns(Range(0, 1)) @requires("self.undec is not None") def prob_error_sign(self): """Probability of incorrect response if a response is forced. Forced responses are selected by the position of the decision variable at the end of the time limit T_dur. This is only available for the implicit method. """ return self.prob_error() + np.sum(self.undec[:len(self.undec) // 2]) @accepts(Self) @requires('self.prob_correct() > 0') @returns(Positive0) def mean_decision_time(self): """The mean decision time in the correct trials (excluding undecided trials).""" return fsum((self.corr) * self.model.t_domain()) / self.prob_correct() @accepts(Self, Natural1, seed=Natural0) @returns(Sample) @ensures("len(return) == k") def resample(self, k=1, seed=0): """Generate a list of reaction times sampled from the PDF. `k` is the number of TRIALS, not the number of samples. Since we are only showing the distribution from the correct trials, we guarantee that, for an identical seed, the sum of the two return values will be less than `k`. If no undecided trials exist, the sum of return values will be equal to `k`. This relies on the assumption that reaction time cannot be less than 0. Returns a Sample object representing the distribution. """ # Exclude the last point in the t domain because we will add # uniform noise to the sample and this would put us over the # model's T_dur. shorter_t_domain = self.model.t_domain()[:-1] shorter_pdf_corr = self.pdf_corr()[:-1] shorter_pdf_corr[-1] += self.pdf_corr()[-1] shorter_pdf_err = self.pdf_err()[:-1] shorter_pdf_err[-1] += self.pdf_err()[-1] # Concatenate the correct and error distributions as well as # their probabilities, and add an undecided component on the # end. Shift the error t domain by the maximum plus one. shift = np.max(shorter_t_domain) + 1 combined_domain = list(shorter_t_domain) + list(shorter_t_domain + shift) + [-1] combined_probs = list(shorter_pdf_corr * self.model.dt) + list( shorter_pdf_err * self.model.dt) + [self.prob_undecided()] if fsum(combined_probs) != 1: print("Warning, distribution sums to %f rather than 1" % fsum(combined_probs)) # Each point x on the pdf represents the space from x to x+dt. # So sample and then add uniform noise to each element. samp = np.random.choice(combined_domain, p=combined_probs, replace=True, size=k) samp += np.random.uniform(0, self.model.dt, k) aa = np.asarray undecided = np.sum(samp == -1) samp = samp[samp != -1] # Remove undecided trials # Find correct and error trials corr_sample = samp[samp < shift] err_sample = samp[samp >= shift] - shift # Build Sample object conditions = { k: (aa([v] * len(corr_sample)), aa([v] * len(err_sample)), aa([v] * int(undecided))) for k, v in self.conditions.items() } return Sample(corr_sample, err_sample, undecided, **conditions)
class Sample(object): """Describes a sample from some (empirical or simulated) distribution. Similarly to Solution, this is a glorified container for three items: a list of correct reaction times, a list of error reaction times, and the number of undecided trials. Each can have different properties associated with it, known as "conditions" elsewhere in this codebase. This is to specifiy the experimental parameters of the trial, to allow fitting of stimuli by (for example) color or intensity. To specify conditions, pass a keyword argument to the constructor. The name should be the name of the property, and the value should be a tuple of length two or three. The first element of the tuple should be a list of length equal to the number of correct trials, and the second should be equal to the number of error trials. If there are any undecided trials, the third argument should contain a list of length equal to `undecided`. Optionally, additional data can be associated with each independent data point. These should be passed as keyword arguments, where the keyword name is the property and the value is a tuple. The tuple should have either two or three elements: the first two should be lists of properties for the correct and error reaction times, where the properties correspond to reaction times in the correct or error lists. Optionally, a third list of length equal to the number of undecided trials gives a list of conditions for these trials. If multiple properties are passed as keyword arguments, the ordering of the undecided properties (in addition to those of the correct and error distributions) will correspond to one another. """ @classmethod def _test(cls, v): # Most testing is done in the constructor and the data is read # only, so this isn't strictly necessary assert type(v) is cls @staticmethod def _generate(): aa = lambda x : np.asarray(x) yield Sample(aa([.1, .2, .3]), aa([.2, .3, .4]), undecided=0) yield Sample(aa([.1, .2, .3]), aa([]), undecided=0) yield Sample(aa([]), aa([.2, .3, .4]), undecided=0) yield Sample(aa([.1, .2, .3]), aa([.2, .3, .4]), undecided=5) def __init__(self, sample_corr, sample_err, undecided=0, **kwargs): assert sample_corr in NDArray(d=1, t=Number), "sample_corr not a numpy array, it is " + str(type(sample_corr)) assert sample_err in NDArray(d=1, t=Number), "sample_err not a numpy array, it is " + str(type(sample_err)) assert undecided in Natural0(), "undecided not a natural number" self.corr = sample_corr self.err = sample_err self.undecided = undecided # Values should not change self.corr.flags.writeable = False self.err.flags.writeable = False # Make sure the kwarg parameters/conditions are in the correct # format for _,v in kwargs.items(): # Make sure shape and type are correct assert isinstance(v, tuple) assert len(v) in [2, 3] assert v[0] in NDArray(d=1) assert v[1] in NDArray(d=1) assert len(v[0]) == len(self.corr) assert len(v[1]) == len(self.err) # Make read-only v[0].flags.writeable = False v[1].flags.writeable = False if len(v) == 3: assert len(v[2]) == undecided else: assert undecided == 0 self.conditions = kwargs def __len__(self): """The number of samples""" return len(self.corr) + len(self.err) + self.undecided def __iter__(self): """Iterate through each reaction time, with no regard to whether it was a correct or error trial.""" return np.concatenate([self.corr, self.err]).__iter__() def __eq__(self, other): if not np.allclose(self.corr, other.corr) or \ not np.allclose(self.err, other.err) or \ self.undecided != other.undecided: return False for k in self.conditions: if k not in other.conditions: return False if np.issubdtype(self.conditions[k][0].dtype, np.floating) and \ np.issubdtype(self.conditions[k][0].dtype, np.floating): compare_func = np.allclose else: compare_func = lambda x,y: np.all(x == y) if not compare_func(self.conditions[k][0], other.conditions[k][0]) or \ not compare_func(self.conditions[k][1], other.conditions[k][1]): return False if len(self.conditions[k]) == 3 and \ len(other.conditions[k]) == 3 and \ not compare_func(self.conditions[k][2], other.conditions[k][2]): return False return True def __add__(self, other): assert sorted(self.conditions.keys()) == sorted(other.conditions.keys()), "Canot add with unlike conditions" corr = np.concatenate([self.corr, other.corr]) err = np.concatenate([self.err, other.err]) undecided = self.undecided + other.undecided conditions = {} for k in self.conditions.keys(): sc = self.conditions oc = other.conditions bothc = np.concatenate([sc[k][0], oc[k][0]]) bothe = np.concatenate([sc[k][1], oc[k][1]]) bothn = np.concatenate([sc[k][2] if len(sc[k]) == 3 else [], oc[k][2] if len(oc[k]) == 3 else []]) conditions[k] = (bothc, bothe, bothn) return Sample(corr, err, undecided, **conditions) @staticmethod @accepts(NDArray(d=2, t=Number), List(String)) @returns(Self) @requires('data.shape[1] >= 2') @requires('set(list(data[:,1])) - {0, 1} == set()') @requires('all(data[:,0].astype("float") == data[:,0])') @requires('data.shape[1] - 2 == len(column_names)') @ensures('len(column_names) == len(return.condition_names())') def from_numpy_array(data, column_names): """Generate a Sample object from a numpy array. `data` should be an n x m array (n rows, m columns) where m>=2. The first column should be the response times, and the second column should be whether the trial was correct or an error (1 == correct, 0 == error). Any remaining columns should be conditions. `column_names` should be a list of length m of strings indicating the names of the conditions. The order of the names should correspond to the order of the columns. This function does not yet work with undecided trials. """ c = data[:,1].astype(bool) nc = (1-data[:,1]).astype(bool) def pt(x): # Pythonic types arr = np.asarray(x) if np.all(arr == np.round(arr)): arr = arr.astype(int) return arr conditions = {k: (pt(data[c,i+2]), pt(data[nc,i+2]), []) for i,k in enumerate(column_names)} return Sample(pt(data[c,0]), pt(data[nc,0]), 0, **conditions) @staticmethod @accepts(Unchecked, String, String) # TODO change unchecked to pandas @returns(Self) @requires('df.shape[1] >= 2') @requires('rt_column_name in df') @requires('correct_column_name in df') @requires('not np.any(np.isnan(df))') @requires('len(np.setdiff1d(df[correct_column_name], [0, 1])) == 0') @requires('all(df[rt_column_name].astype("float") == df[rt_column_name])') @ensures('len(df) == len(return)') def from_pandas_dataframe(df, rt_column_name, correct_column_name): """Generate a Sample object from a pandas dataframe. `df` should be a pandas array. `rt_column_name` and `correct_column_name` should be strings, and `df` should contain columns by these names. The column with the name `rt_column_name` should be the response times, and the column with the name `correct_column_name` should be whether the trial was correct or an error (1 == correct, 0 == error). Any remaining columns should be conditions. This function does not yet work with undecided trials. """ if np.mean(df[rt_column_name]) > 50: print("Warning: RTs should be specified in seconds, not milliseconds") c = df[correct_column_name].astype(bool) nc = (1-df[correct_column_name]).astype(bool) def pt(x): # Pythonic types arr = np.asarray(x) if np.all(arr == np.round(arr)): arr = arr.astype(int) return arr column_names = [e for e in df.columns if not e in [rt_column_name, correct_column_name]] conditions = {k: (pt(df[c][k]), pt(df[nc][k]), []) for k in column_names} return Sample(pt(df[c][rt_column_name]), pt(df[nc][rt_column_name]), 0, **conditions) def items(self, correct): """Iterate through the reaction times. This takes only one argument: a boolean `correct`, true if we want to iterate through the correct trials, and false if we want to iterate through the error trials. For each iteration, a two-tuple is returned. The first element is the reaction time, the second is a dictionary containing the conditions associated with that reaction time. """ return _Sample_Iter_Wraper(self, correct=correct) @accepts(Self) @returns(Self) def subset(self, **kwargs): """Subset the data by filtering based on specified properties. Each keyword argument should be the name of a property. These keyword arguments may have one of three values: - A list: For each element in the returned subset, the specified property is in this list of values. - A function: For each element in the returned subset, the specified property causes the function to evaluate to True. - Anything else: Each element in the returned subset must have this value for the specified property. Return a sample object representing the filtered sample. """ mask_corr = np.ones(len(self.corr)).astype(bool) mask_err = np.ones(len(self.err)).astype(bool) mask_undec = np.ones(self.undecided).astype(bool) for k,v in kwargs.items(): if hasattr(v, '__call__'): mask_corr = np.logical_and(mask_corr, [v(i) for i in self.conditions[k][0]]) mask_err = np.logical_and(mask_err, [v(i) for i in self.conditions[k][1]]) mask_undec = [] if self.undecided == 0 else np.logical_and(mask_undec, [v(i) for i in self.conditions[k][2]]) elif hasattr(v, '__contains__'): mask_corr = np.logical_and(mask_corr, [i in v for i in self.conditions[k][0]]) mask_err = np.logical_and(mask_err, [i in v for i in self.conditions[k][1]]) mask_undec = [] if self.undecided == 0 else np.logical_and(mask_undec, [i in v for i in self.conditions[k][2]]) else: mask_corr = np.logical_and(mask_corr, [i == v for i in self.conditions[k][0]]) mask_err = np.logical_and(mask_err, [i == v for i in self.conditions[k][1]]) mask_undec = [] if self.undecided == 0 else np.logical_and(mask_undec, [i == v for i in self.conditions[k][2]]) filtered_conditions = {k : (np.asarray(list(itertools.compress(v[0], mask_corr))), np.asarray(list(itertools.compress(v[1], mask_err))), (np.asarray(list(itertools.compress(v[2], mask_undec))) if len(v) == 3 else np.asarray([]))) for k,v in self.conditions.items()} return Sample(np.asarray(list(itertools.compress(self.corr, list(mask_corr)))), np.asarray(list(itertools.compress(self.err, list(mask_err)))), sum(mask_undec), **filtered_conditions) @accepts(Self) @returns(List(String)) def condition_names(self): """The names of conditions which hold some non-zero value in this sample.""" return list(self.conditions.keys()) @accepts(Self, String) @requires('cond in self.condition_names()') @returns(List(Unchecked)) def condition_values(self, cond): """The values of a condition that have at least one element in the sample. `cond` is the name of the condition from which to get the observed values. Returns a list of these values. """ cs = self.conditions cvs = set(cs[cond][0]).union(set(cs[cond][1])) if len(cs[cond]) == 3: cvs = cvs.union(set(cs[cond][2])) return sorted(list(cvs)) @accepts(Self, Or(Nothing, List(String))) @returns(List(Conditions)) def condition_combinations(self, required_conditions=None): """Get all values for set conditions and return every combination of them. Since PDFs of solved models in general depend on all of the conditions, this returns a list of dictionaries. The keys of each dictionary are the names of conditions, and the value is a particular value held by at least one element in the sample. Each list contains all possible combinations of condition values. If `required_conditions` is iterable, only the conditions with names found within `required_conditions` will be included. """ cs = self.conditions conditions = [] names = self.condition_names() if required_conditions is not None: names = [n for n in names if n in required_conditions] for c in names: conditions.append(list(set(cs[c][0]).union(set(cs[c][1])))) combs = [] for p in itertools.product(*conditions): if len(self.subset(**dict(zip(names, p)))) != 0: combs.append(dict(zip(names, p))) if len(combs) == 0: # Generally not needed since iterools.product does this return [{}] return combs @staticmethod @accepts(dt=Positive, T_dur=Positive) @returns(NDArray(d=1, t=Positive0)) #@requires('T_dur/dt < 1e5') # Too large of a number def t_domain(dt=.01, T_dur=2): """The times that corresponds with pdf/cdf_corr/err parameters (their support).""" return np.linspace(0, T_dur, int(T_dur/dt)+1) @accepts(Self, dt=Positive, T_dur=Positive) @returns(NDArray(d=1, t=Positive0)) #@requires('T_dur/dt < 1e5') # Too large of a number @ensures('len(return) == len(self.t_domain(dt=dt, T_dur=T_dur))') def pdf_corr(self, dt=.01, T_dur=2): """The correct component of the joint PDF.""" return np.histogram(self.corr, bins=int(T_dur/dt)+1, range=(0-dt/2, T_dur+dt/2))[0]/len(self)/dt # dt/2 terms are for continuity correction @accepts(Self, dt=Positive, T_dur=Positive) @returns(NDArray(d=1, t=Positive0)) #@requires('T_dur/dt < 1e5') # Too large of a number @ensures('len(return) == len(self.t_domain(dt=dt, T_dur=T_dur))') def pdf_err(self, dt=.01, T_dur=2): """The error (incorrect) component of the joint PDF.""" return np.histogram(self.err, bins=int(T_dur/dt)+1, range=(0-dt/2, T_dur+dt/2))[0]/len(self)/dt # dt/2 terms are for continuity correction @accepts(Self, dt=Positive, T_dur=Positive) @returns(NDArray(d=1, t=Positive0)) #@requires('T_dur/dt < 1e5') # Too large of a number @ensures('len(return) == len(self.t_domain(dt=dt, T_dur=T_dur))') def cdf_corr(self, dt=.01, T_dur=2): """The correct component of the joint CDF.""" return np.cumsum(self.pdf_corr(dt=dt, T_dur=T_dur))*dt @accepts(Self, dt=Positive, T_dur=Positive) @returns(NDArray(d=1, t=Positive0)) @ensures('len(return) == len(self.t_domain(dt=dt, T_dur=T_dur))') def cdf_err(self, dt=.01, T_dur=2): """The error (incorrect) component of the joint CDF.""" return np.cumsum(self.pdf_err(dt=dt, T_dur=T_dur))*dt @accepts(Self) @returns(Range(0, 1)) @requires("len(self) > 0") def prob_correct(self): """The probability of selecting the right response.""" return len(self.corr)/len(self) @accepts(Self) @returns(Range(0, 1)) @requires("len(self) > 0") def prob_error(self): """The probability of selecting the incorrect (error) response.""" return len(self.err)/len(self) @accepts(Self) @returns(Range(0, 1)) @requires("len(self) > 0") def prob_undecided(self): """The probability of selecting neither response (undecided).""" return self.undecided/len(self) @accepts(Self) @returns(Range(0, 1)) @requires("len(self) > 0") def prob_correct_forced(self): """The probability of selecting the correct response if a response is forced.""" return self.prob_correct() + self.prob_undecided()/2. @accepts(Self) @returns(Range(0, 1)) @requires("len(self) > 0") def prob_error_forced(self): """The probability of selecting the incorrect response if a response is forced.""" return self.prob_error() + self.prob_undecided()/2.
def _test(v): assert v.pmixturecoef in Range(0, 1), "Invalid pmixture coef" assert v.ratehr in Positive(), "Invalid rate" assert v.ratelr in Positive(), "Invalid rate"
def _test(v): assert v.mappingcoef in Range(0, 1), "Invalid mapping coefficient"
# line for the interactive demo. from paranoid.decorators import accepts, returns, requires, ensures, paranoidclass from paranoid.types import RangeOpenClosed, RangeOpen, Range, Positive0, NDArray, ParametersDict, Natural0, Set, Self, Number, Positive import ddm import numpy as np import scipy # Note that BEGIN and END statements appear throughout this file, and # are markers for keeping the file in sync with the documentation in # the PyDDM Cookbook. # BEGIN utility_functions # Paranoid annotations for correctness @accepts(Range(50, 100), RangeOpen(0, 10), RangeOpenClosed(50, 100)) @requires("coh <= max_coh") @returns(Range(0, 1)) @ensures("return == 0 <--> coh == 50") @ensures("return == 1 <--> coh == max_coh") # Monotonic increasing in coh, decreasing in exponent @ensures( "coh >= coh` and exponent <= exponent` and max_coh == max_coh` --> return >= return`" ) def coh_transform(coh, exponent, max_coh): """Transform coherence to range 0-1. `coh` should be in range 50-`max_coh`, and exponent greater than 0. Returns a number 0-1 via nonlinearity `exponent`. """ coh_coef = (coh - 50) / (max_coh - 50)