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Python Pandas -- DataFrame

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pandas.DataFrame

class pandas.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 column labels. Can be thought of as a dict-like container for Series objects. The primary pandas data structure

Parameters:

data : numpy ndarray (structured or homogeneous), dict, or DataFrame

Dict can contain Series, arrays, constants, or list-like objects

index : Index or array-like

Index to use for resulting frame. Will default to np.arange(n) if no indexing information part of input data and no index provided

columns : Index or array-like

Column labels to use for resulting frame. Will default to np.arange(n) if no column labels are provided

dtype : dtype, default None

Data type to force. Only a single dtype is allowed. If None, infer

copy : boolean, default False

Copy data from inputs. Only affects DataFrame / 2d ndarray input

See also

DataFrame.from_records
constructor from tuples, also record arrays
DataFrame.from_dict
from dicts of Series, arrays, or dicts
DataFrame.from_items
from sequence of (key, value) pairs

pandas.read_csv, pandas.read_table, pandas.read_clipboard

1. 先來個小菜

基於dictionary創建

from pandas import Series, DataFrame
import pandas as pd  
import numpy as np
d = {col1:[1,2],col2:[3,4]}
df = pd.DataFrame(data=d)
print(df)
print(df.dtypes)
#   col1  col2
#0     1     3
#1     2     4
#col1    int64
#col2    int64
#dtype: object

基於Numy的ndarrary

df2 = pd.DataFrame(np.random.randint(low=0, high=10, size=(5, 5)),columns=[a, b, c, d, e])
print (df2)
#   a  b  c  d  e
#0  0  2  4  7  0
#1  6  7  3  4  1
#2  5  3  3  8  7
#3  0  9  4  3  4
#4  7  4  7  0  0

Python Pandas -- DataFrame