Python-科学计算-pandas-16-df与Series数据类型判断

zishendianxia

发布于 2020-11-09 14:17:39

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发布于 2020-11-09 14:17:39

文章被收录于专栏：Python工程师Python工程师

系统：Windows 7 语言版本：Anaconda3-4.3.0.1-Windows-x86_64 编辑器：pycharm-community-2016.3.2 pandas：0.19.2

这个系列讲讲Python的科学计算及可视化
今天讲讲pandas模块
判断数据是否为DataFrame，或为Series

Part 1：背景

当我们使用Df的一些方法时，首先得明确该变量的数据类型是DataFrame，否则有可能会报错
常见错误是，实际数据是一个Series。本文就是说如何识别一个数据是否为DataFrame或Series

Part 2：代码

import pandas as pd

dict_1 = {"time": ["2019-11-02", "2019-11-03", "2019-11-04", "2019-11-05",
                   "2019-12-02", "2019-12-03", "2019-12-04", "2019-12-05"],
          "pos": ["A", "A", "B", "B", "C", "C", "C", "D"],
          "value1": [10, 20, 30, 40, 50, 60, 70, 80]}

df_1 = pd.DataFrame(dict_1, columns=["time", "pos", "value1"])
print("\n", "df_1", "\n", df_1, "\n")

print(type(df_1))

if isinstance(df_1, pd.DataFrame):
    print("df_1 is DataFrame")
else:
    print("df_1 is not DataFrame")


if isinstance(df_1, pd.Series):
    print("df_1 is series")
else:
    print("df_1 is not series")


se_1 = df_1["time"]
print("\n", "se_1", "\n", se_1, "\n")
print(type(se_1))

if isinstance(se_1, pd.DataFrame):
    print("se_1 is DataFrame")
else:
    print("se_1 is not DataFrame")

if isinstance(se_1, pd.Series):
    print("se_1 is series")
else:
    print("se_1 is not series")

代码截图

代码运行命令窗口输出

Part 3：部分代码解读

DataFrame判断：isinstance(df_1, pd.DataFrame)
Series判断：isinstance(se_1, pd.Series)
isinstance可以用来判别其它数据类型，例如以下代码判断是否为列表。对于该方法，难点是某个数据类型如何表述

list_1 = [1, 2, 3]
tuple_1 = (1, 2, 3)if isinstance(list_1, list):
print("is list")if isinstance(tuple_1, list):
print("is list")else:
print("is not list")