Python String isnumeric() 方法

Python String isnumeric()方法是用于字符串处理的内置方法。如果字符串中的所有字符都是数字字符，则 issnumeric() 方法返回“True”，否则返回“False”。该函数用于检查参数是否包含所有数字字符，如整数、分数、下标、上标、罗马数字等（全部用Unicode编写）

Syntax:

string.isnumeric()

Parameters:

isnumeric() does not take any parameters

Returns :

True – If all characters in the string are numeric characters.
False – If the string contains 1 or more non-numeric characters.

Errors and Exceptions:

It does not contain any arguments, therefore, it returns an error if a parameter is passed.
Whitespaces are not considered to be numeric, therefore, it returns “False”
Subscript, Superscript, Fractions, Roman numerals (all written in Unicode)are all considered to be numeric, Therefore, it returns “True”

编程需要懂一点英语

示例 1：

Input : string = '1889345'
Output : True

Input : string = '\u00BD'
Output : True

Input : string = '123ayu456'
Output : False

Python3

# Python code for implementation of isnumeric()
    
# checking for numeric characters
string = '123ayu456'
print(string.isnumeric())
   
string = '123456'
print( string.isnumeric())

Python3

# Python implementation to count numeric characters
# in a string and print non numeric characters
# Given string
# Initialising the counter to 0
string ='123geeks456for789geeks'
count = 0
  
newstring1 =""
newstring2 =""
    
# Iterating the string and checking for numeric characters
# Incrementing the counter if a numeric character is found
# And adding the character to new string if not numeric
# Finally printing the count and the newstring
for a in string:
    if (a.isnumeric()) == True:
        count+= 1
    else:
        newstring1+= a
print(count)
print(newstring1)
   
string ='123ayu456'
count = 0
for a in string:
    if (a.isnumeric()) == True:
        count+= 1
    else:
        newstring2+= a
print(count)
print(newstring2)

输出：

False
True

示例 2：

应用：在Python中给定一个字符串，计算字符串中数字字符的个数，并将它们从字符串中删除，然后打印字符串。

Input : string = '123geeks456for789geeks'
Output : 9
         geeksforgeeks

Input : string = '123ayu456'
Output : 6
         ayu

算法：

将一个空的 NewString 和变量 count 初始化为 0。
逐个字符遍历给定的字符串，直到字符长度，检查字符是否为数字字符。
如果是数字字符，则将计数器加 1 并且不将其添加到新字符串中，否则遍历到下一个字符并继续将字符添加到新字符串中（如果不是数字）。
打印计数器的值和 NewString。

Python3

# Python implementation to count numeric characters
# in a string and print non numeric characters
# Given string
# Initialising the counter to 0
string ='123geeks456for789geeks'
count = 0
  
newstring1 =""
newstring2 =""
    
# Iterating the string and checking for numeric characters
# Incrementing the counter if a numeric character is found
# And adding the character to new string if not numeric
# Finally printing the count and the newstring
for a in string:
    if (a.isnumeric()) == True:
        count+= 1
    else:
        newstring1+= a
print(count)
print(newstring1)
   
string ='123ayu456'
count = 0
for a in string:
    if (a.isnumeric()) == True:
        count+= 1
    else:
        newstring2+= a
print(count)
print(newstring2)

输出：

9
geeksforgeeks
6
ayu