Pandas library (3): Conditional filtering usage of DataFrame

1. Filtering mechanism

You can use the following methods to filter the DataFrame according to the column value to process certain eligible rows

dataframe[ 条件 ]
dataframe[ dataframe["colname"] > value ]
dataframe[ dataframe["colname"] < value ]
dataframe[ dataframe["colname"] != value ]

Second, the derivation process

boolean_array =   dataframe["colname"] > value   ————>   Series type with bool values

dataframe[boolean_array]    —————>  DataFrame filtered
||
dataframe[ dataframe["colname"] > value ]    —————>  DataFrame filtered

Three, multi-condition filtering

dataframe[ dataframe["col1"] > val1 & dataframe["col2"] != val2] 

Reference article:

pandas usage skills [7] how to filter certain rows of DataFrame according to column values