You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
CMSIS-DSP/PythonWrapper/examples/example_1_5.py

159 lines
4.2 KiB
Python

# New functions for version 1.5 of the Python wrapper
import cmsisdsp as dsp
import cmsisdsp.fixedpoint as f
import numpy as np
import math
import colorama
from colorama import init,Fore, Back, Style
from numpy.testing import assert_allclose
from numpy.linalg import qr
def householder(x,eps=1e-16):
#print(x)
v=np.hstack([[1],x[1:]])
alpha = x[0]
xnorm2=x[1:].dot(x[1:])
epsilon=eps
#print(sigma)
if xnorm2<=epsilon:
tau = 0.0
v = np.zeros(len(x))
else:
if np.sign(alpha) <= 0:
beta = math.sqrt(alpha*alpha + xnorm2)
else:
beta = -math.sqrt(alpha*alpha + xnorm2)
r = (alpha - beta)
v = x / r
tau = (beta - alpha) / beta
v[0] = 1
return(v,tau)
init()
def printTitle(s):
print("\n" + Fore.GREEN + Style.BRIGHT + s + Style.RESET_ALL)
def printSubTitle(s):
print("\n" + Style.BRIGHT + s + Style.RESET_ALL)
printTitle("Householder")
VECDIM = 10
a=np.random.randn(VECDIM)
a = a / np.max(np.abs(a))
# Reference
vRef,betaRef = householder(a)
printSubTitle("Householder F32")
betaF32,vF32 = dsp.arm_householder_f32(a,dsp.DEFAULT_HOUSEHOLDER_THRESHOLD_F32)
print(np.isclose(betaRef,betaF32,1e-6,1e-6))
print(np.isclose(vRef,vF32,1e-6,1e-6))
printSubTitle("Householder F64")
betaF64,vF64 = dsp.arm_householder_f64(a,dsp.DEFAULT_HOUSEHOLDER_THRESHOLD_F64)
print(np.isclose(betaRef,betaF64,1e-6,1e-6))
print(np.isclose(vRef,vF64,1e-6,1e-6))
printSubTitle("Householder Proportional F32")
a=np.random.randn(5)
# With the threshold defined with DEFAULT_HOUSEHOLDER_THRESHOLD_F32
# this vector is considered as proportional to (1,0,...)
# and thus the function will return (0,[0,...,0])
a = a / np.max(np.abs(a)) * 1.0e-7
resF32 = dsp.arm_householder_f32(a,dsp.DEFAULT_HOUSEHOLDER_THRESHOLD_F32)
print(resF32)
# With a smaller threshold, a computation is taking place
resF32 = dsp.arm_householder_f32(a,0.001*dsp.DEFAULT_HOUSEHOLDER_THRESHOLD_F32)
print(resF32)
printTitle("QR decomposition")
def checkOrtho(A,err=1e-10):
product = A.T.dot(A)
#print(A)
np.fill_diagonal(product,0)
#print(product)
print(np.max(np.abs(product)))
return (np.all(np.abs(product)<=err))
m=np.array([[-0.35564874, -0.07809871, -0.10350569, -0.50633135, -0.65073484],
[-0.71887395, 0.45257918, 0.29606363, 0.1497621 , 0.07002738],
[-0.50586141, -0.50613839, -0.01650463, -0.29693649, 0.47667742],
[ 0.06802137, 0.07689169, -0.02726221, -0.09996672, 0.15521956],
[ 0.21220523, -0.22273009, 0.78247386, -0.2760002 , -0.24438688],
[ 0.09683658, 0.62026597, 0.26771763, -0.26935342, 0.18443573],
[-0.01014268, 0.27578087, -0.44635721, -0.21827312, -0.26463186],
[-0.20420646, -0.12880459, 0.13207738, 0.65319578, -0.3956695 ]])
rows,columns = m.shape
# The CMSIS-DSP C functions is requiring two temporary arrays
# To follow the C function as closely as possible, we create
# two arrays. Their size will be used internally by the Python
# wrapper to allocate two temporary buffers.
# Like that you can check you have dimensionned the arrays in the
# right way.
# The content of the temporary buffers is not accesible from the
# Python API. tmpa and tmpb are not modified.
tmpa=np.zeros(rows)
tmpb=np.zeros(rows)
printSubTitle("QR F32")
status,r,q,tau = dsp.arm_mat_qr_f32(m,dsp.DEFAULT_HOUSEHOLDER_THRESHOLD_F32,tmpa,tmpb)
# Status different from 0 if matrix dimensions are not right
# (rows must be >= columns)
#print(status)
#print(q)
#print(r)
#print(tau)
# Check that the matrix Q is orthogonal
assert(checkOrtho(q,err=1.0e-6))
# Remove householder vectors from R matrix
i=1
for c in r.T:
c[i:] = 0
i = i+1
# Check that M = Q R
newm = np.dot(q,r)
assert_allclose(newm,m,2e-6,1e-7)
printSubTitle("QR F64")
status,r,q,tau = dsp.arm_mat_qr_f64(m,dsp.DEFAULT_HOUSEHOLDER_THRESHOLD_F64,tmpa,tmpb)
# Status different from 0 if matrix dimensions are not right
# (rows must be >= columns)
#print(status)
#print(q)
#print(r)
#print(tau)
# Check that the matrix Q is orthogonal
assert(checkOrtho(q,err=1e-14))
# Remove householder vectors from R matrix
i=1
for c in r.T:
c[i:] = 0
i = i+1
# Check that M = Q R
newm = np.dot(q,r)
assert_allclose(newm,m)