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[TOC] # 準備數據 ![](https://box.kancloud.cn/1f34e043c5eb52e02b1d560dc1f2f15a_1034x338.png) 我們把這個csv這個放到代碼下面 # 讀取數據 ~~~ import pandas as pd df = pd.read_csv('./tips.csv') print(df) ~~~ 輸出 ![](https://box.kancloud.cn/a072388a95b2ca1dc4c266097f141f89_1570x712.png) # 指定讀取多少行 head里面參數不寫,默認讀取5行 ~~~ import pandas as pd df = pd.read_csv('./tips.csv') # 指定讀取3行 print(df.head(3)) ~~~ 輸出 ![](https://box.kancloud.cn/f3f37c51c58cce59e2c88605367b8341_1026x268.png) # 返回當前信息 ~~~ import pandas as pd df = pd.read_csv('./tips.csv') print(df.info()) ~~~ 輸出 ~~~ <class 'pandas.core.frame.DataFrame'> RangeIndex: 244 entries, 0 to 243 Data columns (total 7 columns): total_bill 244 non-null float64 tip 244 non-null float64 sex 244 non-null object smoker 244 non-null object day 244 non-null object time 244 non-null object size 244 non-null int64 dtypes: float64(2), int64(1), object(4) memory usage: 13.4+ KB None ~~~ 結構是pandas.core.frame.DataFrame,DataFrame結構,矩陣 RangeIndex索引有244個,0到243 Data columns數據有7列下面就是列的名字了 float64表示類型,object是string串 memory usage占用內存多大 # 打印索引值 ~~~ import pandas as pd df = pd.read_csv('./tips.csv') print(df.index) ~~~ 輸出 ~~~ RangeIndex(start=0, stop=244, step=1) ~~~ # 打印value值 ~~~ import pandas as pd df = pd.read_csv('./tips.csv') print(df.values) ~~~ 輸出 ~~~ [[16.99 1.01 'Female' ..., 'Sun' 'Dinner' 2] [10.34 1.66 'Male' ..., 'Sun' 'Dinner' 3] [21.01 3.5 'Male' ..., 'Sun' 'Dinner' 3] ..., [22.67 2.0 'Male' ..., 'Sat' 'Dinner' 2] [17.82 1.75 'Male' ..., 'Sat' 'Dinner' 2] [18.78 3.0 'Female' ..., 'Thur' 'Dinner' 2]] ~~~ # 打印每個列的dtype值 ~~~ import pandas as pd df = pd.read_csv('./tips.csv') print(df.dtypes) ~~~ 輸出 ~~~ total_bill float64 tip float64 sex object smoker object day object time object size int64 dtype: object ~~~