pdq2: continue work on coefficients

This commit is contained in:
Robert Jördens 2015-04-14 18:14:51 -06:00
parent 9e726d7dd1
commit 9795e83bfc

View File

@ -1,5 +1,16 @@
import numpy as np
from scipy.interpolate import splrep, splev
from scipy.interpolate import splrep, splev, spalde
class CoefficientSource:
def get_times(self, t, speed, clock):
pass
def get_coefficients(self, t, speed):
pass
def get_program(self, dt, u):
pass
def _round_times(times, sample_times=None):
@ -23,16 +34,6 @@ def _interpolate(time, data, sample_times, order=3):
return coeffs
def discrete_compensate(c):
l = len(c)
if l > 2:
c[1] += c[2]/2.
if l > 3:
c[1] += c[3]/6.
c[2] += c[3]
if l > 4:
raise ValueError("only third-order splines supported")
def _zip_program(times, channels, target):
for tc in zip(times, *channels):
@ -54,3 +55,23 @@ def interpolate_channels(times, data, sample_times=None, **kwargs):
channel_coeff = [_interpolate(sample_times, i, **kwargs) for i in data.T]
return _zip_program(duration, np.array(channel_coeff))
# v = np.clip(v/self.max_out, -1, 1)
#
#
def discrete_compensate(c):
"""Compensate spline coefficients for discrete accumulators
Given continuous time b-spline coefficients, this function
compensates for the effect of discrete time steps in the
target devices.
The compensation is performed in-place.
"""
l = len(c)
if l > 2:
c[1] += c[2]/2.
if l > 3:
c[1] += c[3]/6.
c[2] += c[3]
if l > 4:
raise ValueError("only third-order splines supported")