From 6f418a5a837939b132967bcdb3ff0ede6d899bd2 Mon Sep 17 00:00:00 2001 From: Mario Mulansky Date: Tue, 12 May 2015 18:45:03 +0200 Subject: +functions to obtain values of the pwc/pwl profile Added __call__ operators to PieceWiseConst and PieceWiseLin class for obtaining function values at certain points in time. --- pyspike/PieceWiseLinFunc.py | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'pyspike/PieceWiseLinFunc.py') diff --git a/pyspike/PieceWiseLinFunc.py b/pyspike/PieceWiseLinFunc.py index f2442be..b9787eb 100644 --- a/pyspike/PieceWiseLinFunc.py +++ b/pyspike/PieceWiseLinFunc.py @@ -29,6 +29,36 @@ class PieceWiseLinFunc: self.y1 = np.array(y1) self.y2 = np.array(y2) + def __call__(self, t): + """ Returns the function value for the given time t. If t is a list of + times, the corresponding list of values is returned. + + :param: time t, or list of times + :returns: function value(s) at that time(s). + """ + def intermediate_value(x0, x1, y0, y1, x): + """ computes the intermediate value of a linear function """ + return y0 + (y1-y0)*(x-x0)/(x1-x0) + + assert np.all(t >= self.x[0]) and np.all(t <= self.x[-1]), \ + "Invalid time: " + str(t) + + ind = np.searchsorted(self.x, t, side='right') + # correct the cases t == x[0], t == x[-1] + try: + ind[ind == 0] = 1 + ind[ind == len(self.x)] = len(self.x)-1 + except TypeError: + if ind == 0: + ind = 1 + if ind == len(self.x): + ind = len(self.x)-1 + return intermediate_value(self.x[ind-1], + self.x[ind], + self.y1[ind-1], + self.y2[ind-1], + t) + def copy(self): """ Returns a copy of itself -- cgit v1.2.3