We’ll be introducing the python isdecimal() method in this tutorial. What if a user wants to check whether a given string contains a number or more specifically a decimal number or not? That can be a case when the user needs to convert the string to any other number types like integer or float or etc..<\/p>\n\n\n\n
As a solution to this problem, Python<\/strong> comes with a built-in checking method, isdecimal()<\/code>. Let us dig into the method and consequently understand how the method works and can be used accordingly.<\/p>\n\n\n\n
Python isdecimal() Method Basics<\/h2>\n\n\n\n
In general, the Python isdecimal()<\/code> method directly checks whether all characters in the specified string are decimal<\/strong> characters or not. If yes, then the method returns true<\/code> or else, returns false<\/code>.<\/p>\n\n\n\n
Syntax for Python isdecimal() method<\/h3>\n\n\n\n
Let us look at the syntax for the Python isdecimal()<\/code> method, following which we can use the method.<\/p>\n\n\n
\nstatus = str.isdecimal( )\n<\/pre><\/div>\n\n\n
Here:<\/p>\n\n\n\n
str<\/code> is the string for which we are checking if it comprises of only decimal characters or not<\/li>
status<\/code> stores the value returned by the isdecimal()<\/code> method. That is true<\/strong> for all decimal characters or else, false<\/strong>.<\/li><\/ul>\n\n\n\n
Note<\/strong>: Here, status just holds either true or false, hence the type of status is bool<\/code>.<\/p>\n\n\n\n
Basic example for the isdecimal() method<\/h2>\n\n\n\n
So here is a small example, which explains how to use the isdecimal()<\/code> method for strings in Python<\/strong>.<\/p>\n\n\n
\nstring1="1010"\nprint("String is: ",string1)\nprint("Result: ",string1.isdecimal())\n\nstring2="a10101"\nprint("String is: ",string2)\nprint("Result: ",string2.isdecimal())\n<\/pre><\/div>\n\n\n
Output<\/strong>:<\/p>\n\n\n
\nString is: 1010\nResult: True\nString is: a10101\nResult: False\n<\/pre><\/div>\n\n\n
Here:<\/p>\n\n\n\n
String1<\/strong> consists of all decimal characters. Hence the string1.isdecimal()<\/code> statement returns a True<\/code> result<\/li>
Whereas, string2<\/strong> has a character ‘a’<\/strong> in it. Due to the fact that string2<\/strong> doesn’t comprise of all decimal characters, the result, in this case, is False<\/code>.<\/li><\/ul>\n\n\n\n
Note<\/strong>: The isdecimal()<\/code> method in Python does not consider fractions, subscripts, superscripts, or any other Unicode<\/strong> implemented characters as a decimal or digit characters. Hence, for the presence of any of the numeric characters in a string, the method returns False<\/code>.<\/p>\n\n\n\n
How Python isdecimal() Works<\/h2>\n\n\n\n
The code snippet below illustrates how the isdecimal()<\/code> method in Python for strings works and what it returns.<\/p>\n\n\n
\n# . is not considered as decimal character\nstring1="55.55"\nprint("String is: ",string1)\nprint("Result: ",string1.isdecimal())\n\n#Pure character string\nstring2="AskPython"\nprint("String is: ",string2)\nprint("Result: ",string2.isdecimal())\n\n#U+2082 unicode for subscript 2\nstring3="222\\u2082"\nprint("String is: ",string3)\nprint("Result: ",string3.isdecimal())\n\n#U+2074 unicode for superscript 4\nstring4="34\\u2074"\nprint("String is: ",string4)\nprint("Result: ",string4.isdecimal())\n\n#U+2152unicode for 1\/10 fraction\nstring5="10\\u2152"\nprint("String is: ",string5)\nprint("Result: ",string5.isdecimal())\n\n#@ not considered as decimal character\nstring6="@1234"\nprint("String is: ",string6)\nprint("Result: ",string6.isdecimal())\n<\/pre><\/div>\n\n\n
Output<\/strong>:<\/p>\n\n\n\n
isdecimal() Example Output<\/figcaption><\/figure><\/div>\n\n\n\n
In the code above:<\/p>\n\n\n\n
For string1<\/strong>, the isdecimal()<\/code> method returns a false<\/code> value because of the dot(.<\/strong>) character present in between the digits. The method considers it not to be a decimal character<\/li>
Again for string2<\/strong>, the string completely or purely consists of characters and hence the method returns a false<\/code> result<\/li>
For all the strings<\/strong>, string3<\/strong>, string4<\/strong> and string5<\/strong>. The isdecimal()<\/code> method returns false<\/code> because all of them contain Unicode values corresponding to non-digit numerical characters<\/li>
At last for string6<\/strong> too, the method returns a false<\/code> because of the fact that the string contains the ‘@<\/strong>‘ character, which again is a non-decimal character.<\/li><\/ul>\n\n\n\n
Conclusion<\/h2>\n\n\n\n
So, in this tutorial, we learned about the built-in string isdecimal()<\/code> method in Python<\/strong>, how it is used as well as how it works. For any questions feel free to comment below.<\/p>\n\n\n\n
![\"Isdecimal](\"https:\/\/www.askpython.com\/wp-content\/uploads\/2020\/02\/isdecimal-example.png\")