Python check if integer is positive

Python Program to Check if A Number is Positive, Negative, or Zero

In this Python example, we will discuss how can we check if any given number is positive, negative, or zero with explanation and implementation. Let’s get started.

1. What is Number and When is it Positive or Negative?

A number is a mathematical object used to count, measure, and label.

– Wikipedia

In simple words, we can say that number can be an arithmetical value, which can be expressed using different ways like word, symbol, or figure, representing a particular quantity and used for counting and can make the computation possible.

When any given number is greater than zero (0) then the number is said to be a positive number and when any given number is lesser than zero(0) then the number is said to be a negative number.

Example: Input : 4 Output : The number is positive Input : -5 Output : The number is negative

Some of the topics which will be helpful for understanding the program implementation better are:

2. Program to Check if A Number is Positive, Negative, or Zero

As discussed above, when the number is greater than zero then it is positive, and negative when it is lesser than zero and when it is equal to zero then the number is zero.

Hence, for the program implementation, we will use the if…else… condition along with the relational operator.

Let’s implement the code and see how it works.

#Python Program to Check is Number is >0 or 0: print("The given number is Positive number") elif num == 0: print("The given number is Zero") else: print("The given number is Negative number")

Output Enter any Number: 56 The given number is Positive number

In the above program, the given input is greater than zero so the output for the positive number was displayed.

3. Check if Any Number is Positive, Negative, or Zero using Exception Handling

Now, in the above program, we have covered the most basic way of implementation.

We can use the exception handling method if the user provides any other input rather than float value. Let’s use the exception handling method for the same problem and find out the working.

# Python Program to Check is Number is >0 or 0: print("The given number is Positive number") elif num == 0: print("The given number is Zero") elif num < 0: print("The given number is Negative number") except ValueError: print("Sorry, Your Input is Invalid")

Output Enter any Number: 67er Sorry, Your Input is Invalid

In the program, we have taken the input inside the try block and if the input cannot be converted to float then ValueError would have been given as output, but we have raised the exception for ValueError and handled the exception successfully.

4. Conclusion

In this article, we have learned how can we check if any provided number is negative, positive, or zero and also implemented the exception handling in case the output is not a number.

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Python Program to Check if A Number is Positive, Negative, or Zero was last modified: September 19th, 2021 by Garvit Parakh

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How to check if a number is positive or negative in Python: Methods and Best Practices

Learn how to check if a number is positive or negative in Python using if-else statements, abs() method, bit operators, and for loops. Discover the best practices and other methods to improve your programming skills.

• Understanding the Basics: What Makes a Number Positive, Negative, or Zero
• Importance of Knowing How to Check if a Number is Positive or Negative in Programming
• Python Program To Check Entered Number is Positive Or Negative
• Overview of Methods to Check if a Number is Positive or Negative in Python
• Using if-else Statements
• Using the Built-in abs() Method
• Using Bit Operators
• Counting Positive and Negative Numbers in a List
• Other Methods and Best Practices
• Other code samples for checking number's positivity or negativity in Python
• Conclusion
• How do you check if a number is positive or negative?
• How do you know if a number is negative in Python?
• How do you find the positive of a number in Python?
• How to check if a number is positive or negative in C?

As a beginner in Python programming, one of the essential skills that you need to learn is how to determine whether a number is positive, negative, or zero. Being able to distinguish between positive, negative, and zero numbers is fundamental in programming, especially when working with mathematical operations. In this article, we will cover the different methods and best practices to check if a number is positive or negative in Python.

Understanding the Basics: What Makes a Number Positive, Negative, or Zero

Before diving into the different methods to check if a number is positive or negative in Python, it is crucial to understand what makes a number positive, negative, or zero. A number is positive if it is greater than zero, negative if it is less than zero, and zero if it is equal to zero. For example, 5 is a positive number, -5 is a negative number, and 0 is neither positive nor negative.

Importance of Knowing How to Check if a Number is Positive or Negative in Programming

In programming, it is common to perform mathematical operations that require determining the sign of a number. For instance, when working with financial data, you might need to calculate the difference between two values, and knowing whether the result is positive or negative is essential. Also, when working with conditional statements, you might need to check whether a value is positive, negative, or zero to decide what action to take. Therefore, understanding how to check if a number is positive or negative in programming is crucial.

Python Program To Check Entered Number is Positive Or Negative

In this python programs video tutorial you will learn to write program to check entered number Duration: 6:23

Overview of Methods to Check if a Number is Positive or Negative in Python

There are several methods to check if a number is positive or negative in Python. The most common ones are:

• Using if-else statements
• Using the built-in abs() method
• Using bit operators
• counting positive and negative numbers in a list

In the following sections, we will discuss each of these methods in detail and provide code examples.

Using if-else Statements

One of the simplest methods to check if a number is positive or negative in Python is by using if-else statements. An if-else statement is a control structure that executes a block of code if a certain condition is true, and another block of code if the condition is false.

Here’s an example of how to use if-else statements to check if a number is positive, negative, or zero:

num = float(input("Enter a number: ")) if num > 0: print("The number is positive") elif num == 0: print("The number is zero") else: print("The number is negative") 

In the code above, we first take input from the user as a float using the input() function. We then use an if statement to check if the number is positive, an elif statement to check if the number is zero, and an else statement to check if the number is negative.

Using the Built-in abs() Method

Another method to check if a number is positive or negative in Python is by using the built-in abs() method. The abs() method returns the absolute value of a number, which is its value without regard to its sign. Therefore, if the absolute value of a number is equal to the number itself, it means that the number is positive. If the absolute value of a number is equal to the negative of the number, it means that the number is negative.

Here’s an example of how to use the abs() method to check if a number is positive or negative:

num = float(input("Enter a number: ")) if abs(num) == num: print("The number is positive") else: print("The number is negative") 

In the code above, we use the abs() method to calculate the absolute value of the number. We then compare the absolute value with the original number to determine whether the number is positive or negative.

Using Bit Operators

Bit operators are another method to check if a number is positive or negative in Python. Bit operators are used to perform bitwise operations on binary numbers . In Python, integers are represented as binary numbers, and they can be manipulated using bit operators.

The most common bit operator used to check if a number is positive or negative is the AND operator ( & ). The AND operator returns 1 if both operands are non-zero, and 0 otherwise. Therefore, if we AND a number with its sign bit, we can determine whether the number is positive or negative.

Here’s an example of how to use the AND operator to check if a number is positive or negative:

num = int(input("Enter a number: ")) if num & 0x80000000: print("The number is negative") else: print("The number is positive") 

In the code above, we first take input from the user as an integer using the input() function. We then AND the number with the sign bit ( 0x80000000 ), which has a value of -2147483648 in decimal. If the result is non-zero, it means that the number is negative. Otherwise, the number is positive.

Counting Positive and Negative Numbers in a List

If you have a list of numbers, you can count the number of positive and negative numbers using a for loop and if statements. A for loop is a control structure that allows you to iterate over a sequence of values. In Python, you can use a for loop to iterate over a list of numbers, and use an if statement to check if each number is positive or negative.

Here’s an example of how to count the number of positive and negative numbers in a list:

nums = [5, -3, 0, 7, -1, -8, 2] pos_count = 0 neg_count = 0 for num in nums: if num > 0: pos_count += 1 elif num  0: neg_count += 1 print("Number of positive numbers:", pos_count) print("Number of negative numbers:", neg_count) 

In the code above, we first define a list of numbers. We then use a for loop to iterate over the list, and use an if statement to check if each number is positive or negative. We keep track of the number of positive and negative numbers using two variables ( pos_count and neg_count ). Finally, we print the number of positive and negative numbers.

Other Methods and Best Practices

Apart from the methods discussed above, other programming languages also have their own ways of checking if a number is positive or negative. For example, in C++, you can use the signbit() function from the library to check the sign of a number. In Java, you can use the Math.signum() method to get the sign of a number. In Kotlin, you can use the Math.sign() function to get the sign of a number.

Here are some best practices to keep in mind when checking if a number is positive or negative in Python:

• Use descriptive variable names: When working with numbers, it is essential to use descriptive variable names that indicate the purpose of the variable.
• Use comments: Use comments to explain the purpose of the code and how it works. This can help other developers understand your code and make it easier to maintain.
• Test the program with different inputs: When testing your program, make sure to test it with different types of inputs, such as positive, negative, and zero numbers. This can help you identify any bugs or errors in your code.

Other code samples for checking number's positivity or negativity in Python

In Python , for example, check if variable is positive python code sample

num = int(input("Input a number")) if num >= 0: print("Positive Number") else: print("Negative Number")

In Python , for example, how to check if number is negative in python code sample

num = -10if num < 0: print(f"number you entered:is negative")

Conclusion

In this article, we have covered the different methods and best practices for checking if a number is positive or negative in Python. We have discussed using if-else statements, the built-in abs() method, bit operators, and counting positive and negative numbers in a list. We have also discussed other methods used in other programming languages and some best practices to follow when working with numbers. By following the methods and best practices outlined in this article, you can become proficient in checking if a number is positive or negative in Python.

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