用python和numpy處理數據次數比較多,寫了幾個小函數,可以方便地讀寫數據:
# -*- coding: utf-8 -*-#----------------------------------------------------------------------# FileName:gettxtdata.py#功能:讀取字符串和文件中的數值數據(浮點數)#主要提供類似matlab中的dlmread和dlmwrite函數#同時提供loadtxtdata和savetxtdata函數#Data: 2013-1-10#Author:吳徐平#----------------------------------------------------------------------import numpy#----------------------------------------------------------------------def StringToDoubleArray(String): """ #將字符串中的所有非Double類型的字符全部替換成空格 #以'#'開頭注釋直至行尾,都被清空 #返回一維numpy.array數組 """ from StringIO import StringIO import re DataArray=numpy.empty([0],numpy.float64) if len(String.strip())>0: #清空注釋行,都是以'#'開頭子字符 doublestring=re.sub('#.*$', " ", String, count=0, flags=re.IGNORECASE) #刪除非數字字符 doublestring=re.sub('[^0-9.e+-]', " ", doublestring, count=0, flags=re.IGNORECASE) #去掉不正確的數字格式(代碼重復是有必要的) doublestring=re.sub('[.e+-](?=/s)', " ", doublestring, count=0, flags=re.IGNORECASE) doublestring=re.sub('[.e+-](?=/s)', " ", doublestring, count=0, flags=re.IGNORECASE) doublestring=re.sub('[e+-]$', " ", doublestring, count=0, flags=re.IGNORECASE) doublestring=re.sub('[e+-]$', " ", doublestring, count=0, flags=re.IGNORECASE) #去掉首尾空格 doublestring=doublestring.strip() if len(doublestring)>0: StrIOds=StringIO(doublestring) DataArray= numpy.genfromtxt(StrIOds) return DataArray#----------------------------------------------------------------------def GetDoubleListFromString(String): """ #使用換行符分割字符串 #將字符串中的所有非Double類型的字符全部替換成空格 #以'#'開頭注釋直至行尾,都被清空 #將每一行轉換成numpy.array數組 #返回numpy.array數組的列表 """ from StringIO import StringIO import re DoubleList=[] StringList=String.split('/n')#使用換行符分割字符串 for Line in StringList: if len(Line.strip())>0: #清空注釋行,都是以'#'開頭子字符 doublestring=re.sub('#.*$', " ", Line, count=0, flags=re.IGNORECASE) #刪除非數字字符 doublestring=re.sub('[^0-9.e+-]', " ", doublestring, count=0, flags=re.IGNORECASE) #去掉不正確的數字格式(代碼重復是有必要的) doublestring=re.sub('[.e+-](?=/s)', " ", doublestring, count=0, flags=re.IGNORECASE) doublestring=re.sub('[.e+-](?=/s)', " ", doublestring, count=0, flags=re.IGNORECASE) doublestring=re.sub('[e+-]$', " ", doublestring, count=0, flags=re.IGNORECASE) doublestring=re.sub('[e+-]$', " ", doublestring, count=0, flags=re.IGNORECASE) #去掉首尾空格 doublestring=doublestring.strip() if len(doublestring)>0: StrIOds=StringIO(doublestring) DoubleList.append(numpy.genfromtxt(StrIOds)) return DoubleList #----------------------------------------------------------------------def GetDoubleListFromFile(FileName): """ #將文本文件中的所有Double類型的字符全部替換成numpy.array數組 #每一行都是numpy.array數組 ##返回numpy.array數組的列表 #注意:返回列表的每個元素又都是一個numpy.array數組 #注意:返回列表的每個元素(或文件每行)可以包含不同多個數的數字 """ file=open(FileName, 'r') read_file = file.read() file.close() DoubleList=GetDoubleListFromString(read_file) return DoubleListdef dlmread(FileName,dtype=numpy.float64): """ #Load Data From Txt-File. #分隔符默認是:";",",",空格類 (包括/t)等等 #以#開頭的被認為是注釋,不會被讀取 #Return Value:二維數值數組(numpy.ndarray) #對文本中數據的排列格式要求最低,且容許出現注釋字符,智能化程度最高,但速度較慢 """ DoubleList=GetDoubleListFromFile(FileName) dlsize=[]#每一行數組的大小 for dL in DoubleList: dlsize.append(dL.size) MinColumnSize=min(dlsize)#數組的最大列數 MaxColumnSize=max(dlsize)#數組的最小列數 #數組創建和賦值 DoubleArray=numpy.empty([len(DoubleList),MinColumnSize],dtype=dtype) row=range(0,len(DoubleList)) colum=range(0,MinColumnSize) for i in row: for j in colum: DoubleArray[i][j]=DoubleList[i][j] return DoubleArray#----------------------------------------------------------------------def loadtxtdata(filename,delimiter=""): """ #Load Data From Txt-File with delimiter. #分隔符默認是:";",",",空格類 (包括/t)和自定義的delimiter等 #Return Value: 二維數值數組(numpy.ndarray) #對文本中數據的排列格式要求較高,且不容許出現注釋字符,智能化程度較低,但速度較快 """ from StringIO import StringIO import re file_handle=open(filename,'r') LinesALL=file_handle.read()#讀入字符串 file_handle.close() DelimiterALL=delimiter+",;"#分隔符 SpaceString=" "#空格 for RChar in DelimiterALL: LinesALL=LinesALL.replace(RChar,SpaceString) return numpy.genfromtxt(StringIO(LinesALL)) #---------------------------------------------------------------------- def savetxtdata(filename, X, fmt='%.8e', delimiter=' ', newline='/n'): """ Save Data To Txt-File. """ numpy.savetxt(filename, X, fmt=fmt, delimiter=delimiter, newline=newline) return True #----------------------------------------------------------------------def dlmwrite(filename, X, fmt='%.8e', delimiter=' ', newline='/n'): """ Save Data To Txt-File. """ numpy.savetxt(filename, X, fmt=fmt, delimiter=delimiter, newline=newline) return True #----------------------------------------------------------------------#測試程序 #----------------------------------------------------------------------if __name__ == '__main__': #生成隨機數 data=numpy.random.randn(3,4) filename='D:/x.txt' #寫入文件 dlmwrite(filename,data) x=GetDoubleListFromFile(filename) print(x) print(dlmread(filename)) y=StringToDoubleArray('79l890joj') print(y) z=loadtxtdata(filename) print(z)
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