Note_Tech

All technological notes.

---

Project maintained by simonangel-fong Hosted on GitHub Pages — Theme by mattgraham

Python - Number

Back

• Python - Number
  • Int
  • Float
  • Complex
  • Type Conversion
  • Random Number

---

• There are three numeric types in Python:
  • int
  • float
  • complex

Int

• Int, or integer, is a whole number, positive or negative, without decimals, of unlimited length.

x = 1
y = 35656222554887711
z = -3255522

print(type(x))
print(type(y))
print(type(z))

---

Float

• Float, or “floating point number” is a number, positive or negative, containing one or more decimals.

• Float can also be scientific numbers with an “e” to indicate the power of 10.

x = 1.10
y = 1.0
z = -35.59

x = 35e3
y = 12E4
z = -87.7e100

print(x)  #35000.0
print(y)  #120000.0
print(z)  #-8.77e+101

---

Complex

Complex numbers are written with a “j” as the imaginary part.

x = 3+5j
y = 5j
z = -5j

print(x)    #(3+5j)
print(y)    #5j
print(z)    #(-0-5j)
print(x+y)    #(3+10j)
print(x+z)    #(3+0j)
print(y+z)    #0j
print(x*y)    #(-25+15j)
print(x*z)    #(25-15j)
print(y*z)    #(25-0j)

---

Type Conversion

• convert from one type to another with the int(), float(), and complex() methods

• Note: You cannot convert complex numbers into another number type.

x = 1    # int
y = 2.8  # float

#convert from int to float:
a = float(x)
print(a)    #1.0
print(type(a))  #<class 'float'>

#convert from float to int:
b = int(y)
print(b)    #2
print(type(b))  #<class 'int'>

#convert from int to complex:
c = complex(y)
print(c)    #(2.8+0j)
print(type(c))  #<class 'complex'>

---

Random Number

Python does not have a random() function to make a random number, but Python has a built-in module called random that can be used to make random numbers.

import random

for i in range(3):
    x= random.randrange(1, 10)
    print("x:",x)
'''
x: 6
x: 1
x: 3
'''

---

TOP