读取EIGEVNVAL画能带

# -*- coding: UTF-8 -*-





import numpy as np

from pythtb import *

import pylab as pl



def readEIGENVAL():



    enFermi = -4.9487             #转化为浮点数





    eigfile = 'EIGENVAL'

    fIn = open(eigfile, 'r')

    lines = fIn.readlines()



    tmp = lines[5].rstrip().split()



    nKpts = int(tmp[1])

    nBnds = int(tmp[2])



    # print tmp

    # print 'No. of k-points', nKpts

    # print 'No. of bands', nBnds

    # print '------------------------'



    kpts = np.zeros((nKpts, 3), dtype=np.float)      #nkpts行，3列

    ens = np.zeros((nBnds, nKpts), dtype=np.float)



    for iKpt in range(nKpts):

        tmp = lines[7 + iKpt * (2 + nBnds)].rstrip().split()

        kpts[iKpt, 0] = float(tmp[0])

        kpts[iKpt, 1] = float(tmp[1])

        kpts[iKpt, 2] = float(tmp[2])

        print iKpt, kpts[iKpt,:]                    #得到的是k点坐标



        for iBnd in range(nBnds):

            tmp = lines[8 + iKpt * (2 + nBnds) + iBnd].rstrip().split()

            ens[iBnd, iKpt] = float(tmp[1]) - enFermi         #1为自旋向上，2为向下

            # print iKpt,iBnd,ens[iBnd, iKpt]



    kpts = np.array(kpts)           #把所有的k点放到一个列表里面

    # print kpts

    return nKpts, nBnds, kpts, ens, enFermi



nKpts, nBnds, kpts, ens, enFermi = readEIGENVAL()



print nKpts, nBnds



pl.figure(figsize=(16.0, 12.4))

pl.subplots_adjust(wspace=0.35)

pl.ylim(-10,10)

pl.xlim(0,nKpts)     #x轴坐标，即k点范围

pl.grid(True)



for i in range(nBnds):

    print i

    pl.plot(ens[i], 'g-', ms=5, mew=1)

# pl.plot(ens[8], 'g-', ms=5, mew=1)

# pl.plot(ens[9], 'g-', ms=5, mew=1)





pl.title(r'$\Gamma$')

pl.ylabel("Energy")

pl.show()