python常用命令有哪些

import pandas as pd 
df=pd.read_csv(r’data/data.csv’)

data=df.sort_index(axis=0,ascending=False)

data=df.sort([‘date’],ascending=True升序，False降序)

data=data.reset_index(drop=True)

import matplotlib.pyplot as plt 
x=data[‘date’]#日期是字符串形式 
y=data[‘close price’] 
plt.plot_date(x,y)

import numpy as np 
np.std

import math 
math.floor

from scipy import fftpack 
hx= fftpack.hilbert(price)

data.order()

data.diff(1)#一阶差分
dataframe 删除元素 
data.drop(元素位置)

import itertools 
a = [[1,2,3],[4,5,6], [7], [8,9]] 
out = list(itertools.chain.from_iterable(a))

data.columns=[‘num’,’price’]

import numpy as np 
data= data.drop(data.loc[np.isnan(data.name.values)].index)

t=data.time.tolist() 
date_time = datetime.datetime.strptime(str(t),’%Y-%m-%d %H:%M:%S’) 
date_time=datetime.date(date_time.year,date_time.month,date_time.day) 
past= date_time - datetime.timedelta(days=n*365)

np.sign

label={‘11’:’TP’,’1-1’:’FN’,’-11’:’FP’,’-1-1’:’TN’} 
for i in range(len(data1)): 
state=str(int(data1[i]))+str(int(data2[i])) 
result.append(label[state])

from matplotlib.font_manager import FontProperties 
font_set = FontProperties(fname=r”c:\windows\fonts\simsun.ttc”, size=15) 
plt.title(u’中文’, fontproperties=font_set）

from time import time 
time1=time() 
time2=time() 
print(time2-time1)