Rev. | 6b453e7e4e80512f197f1785b6a7433f06dae809 |
---|---|
大小 | 10,818 字节 |
时间 | 2013-01-23 07:25:28 |
作者 | Lorenzo Isella |
Log Message | Now the code can also read an aggregate structure. |
#!/usr/bin/env python
import scipy as s
# import pylab as p
import numpy as n
import sys
import string
import scipy.linalg as sl
def generate_chain(k,radius):
my_mat=s.zeros(3*k).reshape((k,3))
mon_pos=s.arange(k)*radius*2.
my_mat[:,0]=mon_pos
return my_mat
def montecarlo_calc(N,cluster, radius, Rc):
counter=0
for i in xrange(N):
pt=random_in_circle(Rc)
counter=counter+accept_reject_point(pt, cluster, radius)
area=s.pi*Rc*Rc
projected_area=area*counter/N
return projected_area
def montecarlo_calc_square(N,cluster, radius, Rc):
counter=0
for i in xrange(N):
pt=random_in_square(Rc)
counter=counter+accept_reject_point(pt, cluster, radius)
area=4.*Rc*Rc
projected_area=area*counter/N
return projected_area
def iterate_MC_rect(N_iter,N,ini_cluster, radius):
area_list=s.zeros(0)
for i in xrange(N_iter):
print "i is, ", i
cluster2=rotate_cluster(ini_cluster)
cluster_pro=project_cluster_xy(cluster2)
calc_area=montecarlo_calc_rect(N,cluster_pro, radius)
area_list=s.hstack((area_list,calc_area))
return area_list
def montecarlo_calc_rect(N,cluster, radius):
rect=build_rect(cluster, radius)
# print "rect is, ", rect
counter=0
for i in xrange(N):
pt=random_in_rect(rect)
counter=counter+accept_reject_point(pt, cluster, radius)
area=rect[2,0]*rect[2,1]
projected_area=area*counter/N
print "the projected area is, ", projected_area
return projected_area
def build_rect(cluster, rmon):
extreme_left_x=min(cluster[:,0])-rmon
extreme_right_x=max(cluster[:,0])+rmon
extreme_lower_y=min(cluster[:,1])-rmon
extreme_upper_y=max(cluster[:,1])+rmon
Lx=abs(extreme_right_x-extreme_left_x)
Ly=abs(extreme_upper_y-extreme_lower_y)
res=s.array([[extreme_left_x, extreme_right_x],\
[extreme_lower_y, extreme_upper_y],\
[Lx,Ly]])
return res
def random_in_rect(rect):
x=s.random.uniform(rect[0,0],rect[0,1],1)[0]
y=s.random.uniform(rect[1,0],rect[1,1],1)[0]
res=s.array([[x, y]])
# res=s.vstack((x,y))
return(res)
def accept_reject_point(pt, cluster, radius):
distmin=min(s.ravel(euclidean_distances(pt,cluster)))
res=distmin<=radius
return (res)
def random_in_square(Rc):
x=s.random.uniform(-Rc,Rc,1)[0]
y=s.random.uniform(-Rc,Rc,1)[0]
res=s.array([[x, y]])
# res=s.vstack((x,y))
return(res)
def random_in_circle(Rc):
#generate random number inside a circle of
#radius Rc and centered in (0,0)
r=s.random.uniform(0.,Rc,1)[0]
theta=s.random.uniform(0.,2*s.pi,1)[0]
L=s.sqrt(r)
x=L*s.cos(theta)
y=L*s.sin(theta)
res=s.array([[x, y]])
# res=s.vstack((x,y))
return(res)
def calculate_Rc(cluster,r_mon):
distmax=max(s.ravel(euclidean_distances(cluster,cluster)))
res=distmax/2.+r_mon
return (res)
def rotate_cluster(cluster):
random_rot_mat= random_rot()
n_row_col=s.shape(cluster)
cluster_rot=s.zeros(s.prod(n_row_col)).reshape((n_row_col[0],\
n_row_col[1]))
for i in s.arange(n_row_col[0]):
cluster_rot[i,:]=s.dot(random_rot_mat, cluster[i,:])
return cluster_rot
def random_rot():
theta=s.arccos(1.-2.*s.random.uniform(0.,1.,1)[0])-s.pi/2.
phi=s.random.uniform(-s.pi,s.pi,1)[0]
psi=s.random.uniform(-s.pi,s.pi,1)[0]
oneone=s.cos(theta)*s.cos(psi)
onetwo=-s.cos(phi)*s.sin(psi)+s.sin(phi)*s.sin(theta)*s.cos(psi)
onethree=s.sin(phi)*s.sin(psi)+s.cos(phi)*s.sin(theta)*s.cos(psi)
twoone= s.cos(theta)*s.sin(psi)
twotwo=s.cos(phi)*s.cos(psi)+s.sin(phi)*s.sin(theta)*s.sin(psi)
twothree=-s.sin(phi)*s.cos(psi)+s.cos(phi)*s.sin(theta)*s.sin(psi)
threeone=-s.sin(theta)
threetwo=s.sin(phi)*s.cos(theta)
threethree=s.cos(phi)*s.cos(theta)
my_mat=s.zeros(9).reshape((3,3))
my_mat[0,0]=oneone
my_mat[0,1]=onetwo
my_mat[0,2]=onethree
my_mat[1,0]=twoone
my_mat[1,1]=twotwo
my_mat[1,2]=twothree
my_mat[2,0]=threeone
my_mat[2,1]=threetwo
my_mat[2,2]=threethree
return my_mat
def euclidean_distances(X, Y, Y_norm_squared=None, squared=False):
"""
Considering the rows of X (and Y=X) as vectors, compute the
distance matrix between each pair of vectors.
Parameters
----------
X: array of shape (n_samples_1, n_features)
Y: array of shape (n_samples_2, n_features)
Y_norm_squared: array [n_samples_2], optional
pre-computed (Y**2).sum(axis=1)
squared: boolean, optional
This routine will return squared Euclidean distances instead.
Returns
-------
distances: array of shape (n_samples_1, n_samples_2)
Examples
--------
>>> from scikits.learn.metrics.pairwise import euclidean_distances
>>> X = [[0, 1], [1, 1]]
>>> # distrance between rows of X
>>> euclidean_distances(X, X)
array([[ 0., 1.],
[ 1., 0.]])
>>> # get distance to origin
>>> euclidean_distances(X, [[0, 0]])
array([[ 1. ],
[ 1.41421356]])
"""
# should not need X_norm_squared because if you could precompute that as
# well as Y, then you should just pre-compute the output and not even
# call this function.
if X is Y:
X = Y = n.asanyarray(X)
else:
X = n.asanyarray(X)
Y = n.asanyarray(Y)
if X.shape[1] != Y.shape[1]:
raise ValueError("Incompatible dimension for X and Y matrices")
XX = n.sum(X * X, axis=1)[:, n.newaxis]
if X is Y: # shortcut in the common case euclidean_distances(X, X)
YY = XX.T
elif Y_norm_squared is None:
YY = Y.copy()
YY **= 2
YY = n.sum(YY, axis=1)[n.newaxis, :]
else:
YY = n.asanyarray(Y_norm_squared)
if YY.shape != (Y.shape[0],):
raise ValueError("Incompatible dimension for Y and Y_norm_squared")
YY = YY[n.newaxis, :]
# TODO:
# a faster cython implementation would do the dot product first,
# and then add XX, add YY, and do the clipping of negative values in
# a single pass over the output matrix.
distances = XX + YY # Using broadcasting
distances -= 2 * n.dot(X, Y.T)
distances = n.maximum(distances, 0)
if squared:
return distances
else:
return n.sqrt(distances)
euclidian_distances = euclidean_distances # both spelling for backward compat
def find_CM(cluster):
CM=s.mean(cluster, axis=0)
return CM
def relocate_cluster(cluster):
cluster_shift=find_CM(cluster)
cluster[:,0]=cluster[:,0]-cluster_shift[0]
cluster[:,1]=cluster[:,1]-cluster_shift[1]
cluster[:,2]=cluster[:,2]-cluster_shift[2]
return cluster
def project_cluster_xy(cluster):
new_clust=cluster[:,0:2]
return new_clust
###################################
R=0.5 #monomer radius
# diameter=2.*R
N=10000
N_iter=1000
k=8 #number of monomers in my chain
chain=0
if (chain==1):
ini_cluster=generate_chain(k,R)
else:
ini_cluster=n.loadtxt("8mer.csv", delimiter=",")
# ini_cluster=s.arange(6).reshape((2,3))*1.
# ini_cluster[0,0]=4.
# ini_cluster[0,1]=0.
# ini_cluster[0,2]=0.
# ini_cluster[1,0]=2.
# ini_cluster[1,1]=0.
# ini_cluster[1,2]=0.
# ini_cluster=s.arange(9).reshape((3,3))*1.
# ini_cluster[0,0]=0.
# ini_cluster[0,1]=0.
# ini_cluster[0,2]=0.
# ini_cluster[1,0]=2.
# ini_cluster[1,1]=0.
# ini_cluster[1,2]=0.
# ini_cluster[2,0]=4.
# ini_cluster[2,1]=0.
# ini_cluster[2,2]=0.
# print "ini_cluster is, ", ini_cluster
ini_cluster=relocate_cluster(ini_cluster)
print "ini_cluster is, ", ini_cluster
# random_rot_mat= random_rot()
# mat_calc=s.dot( random_rot_mat,s.transpose(random_rot_mat))
# my_det=sl.det(random_rot_mat)
# print "mat_calc is, ", mat_calc
# print "my_det is, ", my_det
# rotated_clust=rotate_cluster(ini_cluster)
# print "rotated_clust is, ", rotated_clust
##############################
# now a test
# rotated_clust=ini_cluster
##################################
# mydist=euclidean_distances(rotated_clust,rotated_clust )
# print "mydist is, ", mydist
# projected_clust=project_cluster_xy(rotated_clust)
# print "projected_clust is, ", projected_clust
# mydistpro=euclidean_distances(projected_clust,projected_clust )
# print "mydistpro is, ", mydistpro
# Rc3D=calculate_Rc(rotated_clust,R)
# print "Rc3D is, ", Rc3D
# Rc=calculate_Rc(projected_clust,R)
# print "Rc is, ", Rc
# pt=random_in_circle(Rc)
# print "pt is, ", pt
# print "s.shape(pt) is, ", s.shape(pt)
# print "s.shape(projected_clust) is, ", s.shape(projected_clust)
# inout=accept_reject_point(pt, projected_clust, R)
# print "inout is, ", inout
# N=100
# print "N is, ", N
# area=montecarlo_calc(N,projected_clust, R, Rc)
# print "area is, ", area
# N=200
# print "N is, ", N
# area=montecarlo_calc(N,projected_clust, R, Rc)
# print "area is, ", area
# N=500
# print "N is, ", N
# area=montecarlo_calc(N,projected_clust, R, Rc)
# print "area is, ", area
# N=1000
# print "N is, ", N
# area=montecarlo_calc(N,projected_clust, R, Rc)
# print "area is, ", area
# N=10000
# print "N is, ", N
# area=montecarlo_calc(N,projected_clust, R, Rc)
# print "area is, ", area
# N=50000
# print "N is, ", N
# area=montecarlo_calc(N,projected_clust, R, Rc)
# print "area is, ", area
############################
# print "and with the square"
# N=500
# print "N is, ", N
# area=montecarlo_calc_square(N,projected_clust, R, Rc)
# print "area is, ", area
# N=1000
# print "N is, ", N
# area=montecarlo_calc_square(N,projected_clust, R, Rc)
# print "area is, ", area
# N=10000
# print "N is, ", N
# area=montecarlo_calc_square(N,projected_clust, R, Rc)
# print "area is, ", area
# N=50000
# print "N is, ", N
# area=montecarlo_calc_square(N,projected_clust, R, Rc)
# print "area is, ", area
# N=200000
# print "N is, ", N
# area=montecarlo_calc_square(N,projected_clust, R, Rc)
# print "area is, ", area
# N=10000
# print "N is, ", N
# area=montecarlo_calc_rect(N,projected_clust, R)
# print "area (with a rect) is, ", area
# N=20000
# print "N is, ", N
# area=montecarlo_calc_rect(N,projected_clust, R)
# print "area (with a rect) is, ", area
# N=50000
# print "N is, ", N
# area=montecarlo_calc_rect(N,projected_clust, R)
# print "area (with a rect) is, ", area
# N=100000
# print "N is, ", N
# area=montecarlo_calc_rect(N,projected_clust, R)
# print "area (with a rect) is, ", area
# N=200000
# print "N is, ", N
# area=montecarlo_calc_rect(N,projected_clust, R)
# print "area (with a rect) is, ", area
area_list=iterate_MC_rect(N_iter,N,ini_cluster, R)
n.savetxt("area_list.dat", area_list)
print("the estimated projected area is, ", s.mean(area_list))
print "So far so good"