Source code for triqs.gf.plot.select_indices

# Copyright (c) 2016 Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
# Copyright (c) 2016 Centre national de la recherche scientifique (CNRS)
# Copyright (c) 2020 Simons Foundation
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You may obtain a copy of the License at
#     https:#www.gnu.org/licenses/gpl-3.0.txt
#
# Authors: Michel Ferrero, Nils Wentzell, tayral

import numpy as np
import math
[docs] def dist(x,y): '''return the 2D distance between x and y''' return math.sqrt((x[0]-y[0])**2+(x[1]-y[1])**2)
[docs] def pick_selection_vec(data, stride): Nmomentum = len(data) data_selected=[] for k in range(0,Nmomentum,stride): data_selected.append(data[k]) return data_selected
[docs] def closest_point_in_line( x, L): '''return the index of the closest point to x in the list of points L''' mins=[] dists=[] if len(L)>0 : min_dist = float('inf'); min_index = 0; ik=0 for k in L: d=dist(x,k); dists.append(d) if d<=min_dist: min_dist = d; min_index = ik; ik+=1 for i in range(len(L)): if dists[i] == min_dist: mins.append(i) return mins; raise Exception("Empty mesh")
[docs] def closest_to(A,B, L, verbose=False): '''returns list of indices of the points in list L (or mesh!) that are closest to the oriented line A->B''' A = np.array(A) B = np.array(B) closest_indices=[] closest_indices_final=[] #discretization of the line Nmesh =2;#at least two points, A and B size_before = -1; while len(closest_indices)!=size_before: size_before = len(closest_indices) closest_indices=[] closest_indices_final=[] for i in range(Nmesh): current_point = A +(B-A)*(i*1.0/(Nmesh-1)); if verbose: print(" current_point is ",current_point) closest = closest_point_in_line(current_point,L)[0]; #print " closest point is ",closest if closest_indices.count(closest)==0: closest_indices_final.append(closest); closest_indices.append(closest); #print "** closest_index size = ",len(closest_indices) Nmesh*=2; return closest_indices_final;
[docs] def select_path_indices(path,mesh,verbose=False): path_indices=[] closest_indices=[] high_sym_pts_indices=[] for i in range(len(path)-1): start = path[i];end = path[i+1]; closest_indices = closest_to(start,end,mesh); if i==0: high_sym_pts_indices.append((0,closest_indices[0])) ratio = dist(start,end)/ len(closest_indices) stride = int(round(len(closest_indices)/dist(start,end)*ratio )) #if verbose: print "stride = ",stride closest_indices = pick_selection_vec(closest_indices,stride ) path_indices.extend( closest_indices) high_sym_pts_indices.append((len(path_indices),closest_indices[-1])) if verbose==False: return path_indices else: return path_indices,high_sym_pts_indices