Various Ways to Output Values with the print Function

When programming, there are often times when you need to check the value of a variable or verify the result of the code execution.

One of the most frequently used functions to make sure a program is working as intended is print.

In this lesson, we will explore formatting methods to make the output of the print function more organized.

In Python, you can use the % operator to neatly insert variable values into a string when outputting.

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# Output: Hello, Python
print("Hello, %s!" % "Python")

The code above uses %s format code inside the print function.

%s is used for strings, and the value after the % operator is substituted as a string.

To print integers, use %d.

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# Output: 3 apples
print("%d apples" % 3)

When formatting multiple values, use parentheses to list the variables separated by commas, like % (name, age).

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name = "GeekHaus"
age = 30

# Output: Name: GeekHaus, Age: 30
print("Name: %s, Age: %d" % (name, age))

As mentioned earlier, %s represents a string, and %d stands for an integer.

In the example above, %s is substituted with the string "GeekHaus", and %d is replaced with the integer 30.

To format floating-point numbers, use %f.

Since Python 3.6, a new string formatting method called f-string has been introduced.

With f-strings, you can directly include variable names and expressions inside curly braces { } by prefixing the string with f.

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name = "GeekHaus"
age = 30

print(f"Name: {name}, Age: {age}")

The code above prints Name: GeekHaus, Age: 30.

f-strings are preferred by many Python developers because they enhance readability and make the code concise.

Additionally, with f-strings, you can call functions inside the curly braces, like f"{name.upper()}".

Note: The upper() function converts all letters in a string to uppercase.

By default, the print function adds a newline after output.

For example, the following code prints 1, 2, 3 on separate lines.

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print(1)
print(2)
print(3)

If you want to print without a newline, you can use the end parameter.

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print(1, end=" ")
print(2, end=" ")
print(3)

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1 2 3

In the code above, end=" " sets a space (" ") instead of a newline after printing each value.

To print multiple values separated by a specific character, use the sep (Separator) parameter.

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print("Python", "coding", "is fun", sep="-")

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Python-coding-is fun

In the code above, sep="-" sets - as the separator between the values to be printed.