import pandas as pd
import xlrd
import numpy as np

xlsfile = r'D:\workfile\uv\wind.xls'
book = xlrd.open_workbook(xlsfile) 
#xlrd用於獲取每個sheet的sheetname  
#count = len(book.sheets())
with pd.ExcelWriter('newxls.xls') as writer:
    for sheet in book.sheets():
        print sheet.name
        df = pd.read_excel(xlsfile,sheet.name,index_col = None
 
)
        df1=df.replace(9999,np.nan).dropna(axis=0)
        df2=df1.iloc[:,:2]
        df3=df1.iloc[:,2]
        #np.sin和np.cos按元素計算，好啊
        df4=(-1)*np.sin(df3)*df1.iloc[:,3]
        df5=(-1)*np.cos(df3)*df1.iloc[:,3]
        #重新拼接
        pieces=[df2,df4,df5]
        df6=pd.concat(pieces,axis=1
 
)
        #對columns重新命名
        column_index={'jingdu':'jingdu','weidu':'weidu',0:'u',1:'v'}
        df7=df6.rename(columns=column_index)
        #結果寫入excel中的sheet
        df7.to_excel(writer,sheet_name = sheet.name)