写给Matlab用户的Python急速入门手册

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%此为octave代码，貌似CSDN不支持matlab高亮。。。这里用的还是python的高亮
x = rand(10,1);
for i = 1:10
    if x(i)<0.3
        fprintf("%f<0.3n",x(i));
    else if x(i)>0.6
        fprintf("%f>0.6n",x(i));
    else
        printf("%fn",x(i));
    end %匹配else if中的if
    end 
end
% 下面为其输出
0.077700<0.3
0.203065<0.3
0.578026
0.752277>0.6
0.380363
0.541303
0.520777
0.031512<0.3
0.042714<0.3
0.986611>0.6
>>

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#此为python代码
import numpy as np
x = np.random.rand(10)
for i in range(10):
    if x[i]< 0.3: print(x[i],"<0.3")
    elif x[i]>0.6: print(x[i],">0.6")
    else: print(x[i])
# 下面为python的输出
0.13810550482646344 <0.3
0.05145857194203651 <0.3
0.40510564390649306
0.01924290850447119 <0.3
0.3126615170549344
0.9716907139903828 >0.6
0.3306312812282888
0.08156490331007271 <0.3
0.24120991717365392 <0.3
0.7177679530429059 >0.6
>>>

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x = [1,2,3,3,2,1];
for i = 1:6
    switch x(i)
        case 1
            disp('one')
        case 2
            disp('two')
        otherwise
            disp('three')
    end
end
% 下面位计算结果
one
two
three
three
two
one

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dic = {1:"one",2:"two",3:"three"}   #定义一个字典
for i in x:
    print(dic[i])

# 下面为其输出结果
one
two
three
three
two
one

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% 此为octave代码
function y = fac(x)
    if x>1
        y = x*fac(x-1);
    else
        y = 1;
    end
end
% 下面位调用结果
>> fac(5)
ans = 120

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# 此为python代码
def fac(x):
    return x*fac(x-1) if x > 1 else 1
#下面为调用
>>> fac(5)
120

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% matlab
>> sqr = @(x) x^2;
>> sqr(3)
ans = 9
>> (@(x) x^2)(5)
ans = 25

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>>> sqr = lambda x:x**2
>>> sqr(3)
9
>>> (lambda x:x**2)(5)
25
>>> fac = lambda x : x*fac(x-1) if x > 1 else 1
>>> fac(5)
120

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# 此为python代码
>>> x = [1,'2',3,[4,5]]
>>> x
[1, '2', 3, [4, 5]]

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% 此为Person.m文件中定义的类
classdef Person
  properties
    Age = 18;
    Gender = "girl";
    Name = "Lily";
  endproperties
  
  methods   %类方法，静态方法需要加Static
    function setName(obj,string)
      obj.Name = string;
    endfunction
    
    function Intro(obj)
      fprintf("I'm %sn",obj.Name);      
    endfunction
  endmethods
endclassdef

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>>> class Person:
...   Age = 18
...   Gender = "girl"
...   Name = "Lily"
...   def setName(self, str):
...     self.Name = str
...   def Intro(self):
...     print("I'm",self.Name)
...
>>> p = Person()
>>> p.setName("wang")
>>> p.Intro()
I'm wang