numbers

I have a Python script which converts a decimal number into a binary one and this obviously uses their input. I would like to have the script validate that the input is a number and not anything else which will stop the script. I have tried an if/else statement but I don't really know how to go about it. I have tried if decimal.isint(): and if decimal.isalpha(): but they just throw up errors when I enter a string. print("Welcome to the Decimal to Binary converter!") while True: print("Type a decimal number you wish to convert:") decimal = int(input()) if decimal.isint(): binary = bin(decimal)

Can someone tell me how to match a number between 1-17 with a regex: I tried [1-9]|1[0-7] but it matches 8 in the 18 for example because of the first part. Any ideas? I don't want to have leading zeros. edited: The problem is I'm trying to validate a UK postcode like to start with: KW1-17 (it could be KW1, KW2 up to KW17) ... and this is just the outward part. The postcode may be KW15 1BM or KW151BM so I can't just use anchors to match the whole string ... it becomes more complicated. You need to put anchors around the regex or it will match substrings: ^(?:[2-9]|1[0-7]?)$ I've also taken the

Through my javascript library, I end up with a string that represents a number. Now I want to preform an addition on that number without it doing a string concatenation instead. The solution is easy ( How do I add an integer value with javascript (jquery) to a value that's returning a string? , How to make an addition instead of a concatenation ) if your number is always in integer. However my string could be a float or an integer, and at the time of the addition, and I don't know which it will be. Is there a way to make sure the addition happens regardless of whether it's a float or integer?

I have a number of 20 digit, which datatype will support to store this number? I have tried long, double but I 'm getting out of range. Number = 48565664968483514466 Then I have to convert this number to Base36 to generate the barcode. BigInteger: The BigInteger class allocates as much memory as it needs to hold all the bits of data it is asked to hold and also provides operations analogues to all of Java's primitive integer operators and for all relevant methods from java.lang.Math. Declare it as BigInteger bi1 = new BigInteger("12345678900123"); To convert your number in base 36: BigInteger

Possible Duplicate: Why not use Double or Float to represent currency? I'm writing a basic command-line program in Java for my high school course. We're only working with variables right now. It's used to calculate the amount of bills and coins of whatever type in your change after a purchase. This is my program: class Assign2c { public static void main(String[] args) { double cost = 10.990; int paid = 20; double change = paid - cost; int five, toonie, loonies, quarter, dime, nickel, penny; five = (int)(change / 5.0); change -= five * 5.0; toonie = (int)(change / 2.0); change -= toonie * 2.0;

I try to check if a variable is an instance of a number of any type ( int , float , Fraction , Decimal , etc.). I cam accross this question and its answer: How to properly use python's isinstance() to check if a variable is a number? However, I would like to exclude complex numbers such as 1j . The class numbers.Real looked perfect but it returns False for Decimal numbers... from numbers Real from decimal import Decimal print(isinstance(Decimal(1), Real)) # False In contradiction, it works fine with Fraction(1) for example. The documentation describes some operations which should work with the