Python supports three different types of numbers:
- Integer (INT)-usually referred to as an integer or integral, is a positive or negative integer, with no decimal points. The Python3 integral type is not limited in size and can be used as a long type, so Python3 does not have a long type of Python2.
- Float (float)-floating-point type consists of integral and fractional parts, and floating-point types can also be represented by scientific notation (2.5e2 = 2.5 x 102 = 250). This is called a floating-point number because, when represented by scientific notation, the decimal position of a floating point number is variable, for example, 1.23x109 and 12.3x108 are exactly equal. Floating-point numbers can be written in mathematical notation, such as 1.23,3.14,-9.01, and so on. But for very large or very small floating-point numbers, it must be expressed in scientific notation, the 10 is replaced with E, 1.23x109 is 1.23e9, or 12.3e8,0.000012 can be written 1.2e-5, and so on. Integers and floating-point numbers are stored inside the computer in different ways, and integer operations are always accurate (is division accurate?). Yes! ), and the floating-point operation may have rounding errors.
- Complex numbers ((complex))-complex numbers are composed of real and imaginary parts, and can be represented by a + BJ, or complex (a, b), where both the real and imaginary part of a complex number are floating-point types. Click here for the plural concept
We use the ID () function to output the address referenced by the variable:
var1 = Print=print(ID (var1))
The above code, output:
20129695362012972736
You will find that Orz, two times the memory address does not want the same. As you can see, the Python numeric data type is used to store numeric values, and the data type is not allowed to change, which means that if you change the value of the numeric data type, the memory space will be redistributed.
The following instance is created when the variable is assigned a value:
var1 = 1= 10
You can also use the DEL statement to delete references to some numeric objects. The syntax for the DEL statement is:
del Var1[,var2[,var3[....,varn] []]
Multiple objects to be deleted are separated by commas ",", for example:
var1 = 1= tendel var1, VAR2
Computer because of the use of binary, so, sometimes hexadecimal notation is convenient, hexadecimal with 0x prefix (lowercase x or uppercase x can) and 0~9,a~f, for example:0xf0,0xabc123 , octal is prefixed with 0o (lowercase o or uppercase o are available) and 0~7, for example:0o37
Number = 0xa0f # hexadecimal number2 = 0o37 # octal print(number) Print(number2)
The above code, output:
257531
Thinking, how to use the program to achieve 10 binary to 2, 8, 16, any of the binary?
Examples of numeric types
int |
float |
Complex |
10 |
0.0 |
3.14j |
100 |
15.20 |
45.j |
-786 |
-21.9 |
9.322e-36j |
080 |
32.3+e18 |
.876j |
-0490 |
-90. |
-.6545+0j |
-0x260 |
-32.54e100 |
3e+26j |
0x69 |
70.2-e12 |
4.53e-7j |
Sometimes, we need to convert the data-built type into the data type, you just need to use the data type as the function name:
- int (x) converts x to an integer.
- Float (x) converts the x to a floating-point number.
- Complex (x) converts x to a complex number, the real part is x, and the imaginary part is divided into 0.
- Complex (x, Y) converts X and Y to a complex number, the real part is x, and the imaginary part is Y. X and y are numeric expressions.
A = 1.0print(int (a))
The above code, output
1
Note: The results of the floating point operations on different machines may vary.
In integer division, Division (/) always returns a floating-point number, and if you want only the result of an integer, discard the possible fractional portion, you can use the operator//:
Print (17/3) # integer division returns floating-point type Print (+//3) # integer division Returns the result of rounding down Print (3%) # The% operator returns the remainder of the Division
The above code, output:
5.66666666666666752
You can use the * * operation to perform a power operation:
Print ('5 squared:', 5 * * 2) Print ('5 of 3 times:', 5 * * 3)
The above code, output:
5 squared:125
Different types of number blending operations convert integers to floating-point numbers:
Print ('3 * value of 3.75/1.5:', 3 * 3.75/1.5)
The above code, output:
3 * Value of 3.75/1.5:7.5
Python3 eighth-Number of data types (numbers)