将合并和对30天窗口的过滤移到一个groupby()中。 对于每个组都要进行一次合并,所以速度会慢一些,但应该使用更少的内存。 选项#1 假设您的数据如下所示(我扩展了您的示例数据): print df company date measure 0 0 2010-01-01 10 1 0 2010-01-15 10 2 0 2010-02-01 10 3 0 2010-02-15 10 4 0...
Thegroupby()methodis a simple but very useful concept in pandas. By usinggroupby(), we can create a grouping of certain values and perform some operations on those values. It splits the object, apply some operations, and then combines them to create a group. Hence a large amount of data...
Python program to vectorize conditional assignment in pandas dataframe # Importing pandas packageimportpandasaspd# Importing numpy packageimportnumpyasnp# Creating a dictionaryd={'x':[0,-4,5,-2,2]}# Creating a DataFramedf=pd.DataFrame(d)# Display original DataFrameprint("Original Dataframe:\n",...