pandas create dataframe from list

background Items Pandas Spark Working style Stand-alone, unable to process large amounts of data Distributed, capable of processing large amounts of data Storage mode Stand-alone cache Can call Persist/cache distributed cache is variable Is Whether Index indexes Automatically created No index Row structure Pandas.series Pyspar

Pandas dataframe the additions and deletions of the summary series of articles: How to create Pandas Daframe Query method of Pandas Dataframe Pandas

Pandas Spark Working style Single machine tool, no parallel mechanism parallelismdoes not support Hadoop and handles large volumes of data with bottlenecks Distributed parallel computing framework, built-in parallel mechanism parallelism, all data and operations are automatically distributed on each cluster node. Process distributed data in a way that handles in-memory data.Supports Hadoop and can handle large amounts of data

Pandas Spark Working style Single machine tool, no parallel mechanism parallelismdoes not support Hadoop and handles large volumes of data with bottlenecks Distributed parallel computing framework, built-in parallel mechanism parallelism, all data and operations are automatically distributed on each cluster node. Process distributed data in a way that handles in-memory data.Supports Hadoop and can handle large amounts of data

': 12, ' C2 ': 120}]DF = PD. DataFrame (INP) for index, row in df.iterrows (): print row[ ' C1 '], Row[ ' C2 ' #10 100 #11 110 #12 + Each iteration of Df.iterrows () is a tuple type that contains the index and the data for each row. Using the Iterrows method, the resulting row is a series,dataframe dtypes will not be retained. The returned series is only a copy of the original

in the sense this they ' re an immutable data structure. Therefore things like: # to create a new column "three" df[' three ') = Df[' One '] * df[' one '] Can ' t exist, just because this kind of affectation goes against the principles of Spark. Another example would is trying to access by index a single element within a DataFrame. Don ' t forget that your ' re using a distributed data structure, not a i

']], columns=['p1', 'p2 ...: ', 'p3'])In [4]: dfOut[4]: p1 p2 p30 GD GX FJ1 SD SX BJ2 HN HB AH3 HEN HEN HLJ4 SH TJ CQ If you only want two rows whose p1 is GD and HN, you can do this: In [8]: df[df.p1.isin(['GD', 'HN'])]Out[8]: p1 p2 p30 GD GX FJ2 HN HB AH However, if we want data except the two rows, we need to bypass the point. The principle is to first extract p1 and convert it to a list, then remove unnecessary rows (values) from the

), columns=['A', 'B', 'C', 'D', 'E']) DataFrame data preview: A B C D E0 0.673092 0.230338 -0.171681 0.312303 -0.1848131 -0.504482 -0.344286 -0.050845 -0.811277 -0.2981812 0.542788 0.207708 0.651379 -0.656214 0.5075953 -0.249410 0.131549 -2.198480 -0.437407 1.628228 Calculate the total data of each column and add it to the end as a new column df['Col_sum'] = df.apply(lambda x: x.sum(), axis=1) Calculates the total data of each row and adds it to

Pandas. DataFrame pandas. class DataFrame (data=none, index=none, columns=none, dtype=none, copy=false) [Source] Two-dimensional size-mutable, potentially heterogeneous tabular data structure with labeled axes (rows and columns). Arithmetic operations align on both row and

[' col_sum ' = df.apply (lambda x:x.sum (), Axis=1) Calculates the sum of each row's data and adds it to the end as a new row df.loc[' row_sum ' = df.apply (lambda x:x.sum ()) Final data results: A B C D E col_sum0 0.673092 0.230338-0.171681 0.312303-0.184813 0.8592381-0.504482-0.344286- 0.050845-0.811277-0.298181-2.0090712 0.542788 0.207708 0.651379-0.656214 0.507595 1.2532563-0.249410 0.131549-2.1984 80-0.437407 1.628228-1.125520row_sum 0.461987 0.225310-1.769627-1.592595 1.652828-1.0220

lines for GD and HN, you can do this: In [8]: Df[df.p1.isin ([' GD ', ' HN '])]out[8]: p1 p2 p30 GD GX FJ2 HN HB AH But if we want data beyond these two lines, we need to get around the point. The principle is to first remove the P1 and convert it to a list, then remove the unwanted rows (values) from the list and then use them in the Dataframeisin() In [9]: Ex_list =