String Formatting#

Introduction #

The .format() method in Python is used to create strings that include variables, expressions, or values. This method replaces curly brace placeholders {} in a string with values provided inside .format().

def main():
    x = 1
    y = 5

    # Display the variables using .format()
    brain.print("Position: ({}, {})".format(x, y))

# VR threads — Do not delete
vr_thread(main)

def main():
    # Display a calculation using .format()
    brain.print("Sum: {}".format(5 + 3))

# VR threads — Do not delete
vr_thread(main)

def main():
    # Display the detected brightness using .format()
    brain.print("Brightness: {}%".format(front_eye.brightness(PERCENT)))

# VR threads — Do not delete
vr_thread(main)

Formatting Numbers with .format – Insert values and expressions into a string.

:.xf – Sets the number of decimal places to show.
round – Rounds a number to a given number of decimal places.
:, – Adds commas as thousands separators.
:.x% – Converts a decimal to a percentage with x decimal places.
:#x – Formats a number as hexadecimal.
:b – Formats a number as binary.

Combining Strings – Combine text and values.

.format() – Combine strings and variables in a single expression.
+ operator – Concatenate strings manually with optional type conversion.

String Methods – Change the case of text.

upper() – Converts all characters to uppercase.
lower() – Converts all characters to lowercase.

Checking for Substrings – Test for presence or position of text.

in – Checks if a word exists in a string.
startswith() – Checks if a string begins with a given value.
endswith() – Checks if a string ends with a given value.

Escape Sequences – Format output with special characters.

\n – Adds a line break (new line).
\t – Adds a tab space between items.

Formatting Numbers with `.format`#

.format can be used to control how numbers appear, including decimal places, rounding, and other formatting styles such as:

Fixed Decimal Places #

.xf controls how many decimal places a number is displayed with.

Usage:
.xf

Parameters	Description
`x`	The amount of decimal places to show.

def main():
    # Display pi with 2 decimal places
    pi = 3.1415926535
    brain.print("Pi: {:.2f}".format(pi))
    # Output: Pi: 3.14

# VR threads — Do not delete
vr_thread(main)

Rounding Numbers #

round rounds a number to a specific number of decimal places before formatting.

Usage:
round(number, x)

Parameters	Description
`number`	The number to round.
`x`	The amount of decimal places to round to.

def main():
    # Display a value rounded to only 2 decimal places
    value = 5.6789
    brain.print("Rounded: {}".format(round(value, 2)))
    # Output: Rounded: 5.68

# VR threads — Do not delete
vr_thread(main)

Thousands Separator #

:, inserts commas as thousands separators to make large numbers more readable.

Usage:
:,

Parameters	Description
	This format specifier has no parameters.

def main():
    # Display a large number separated with commas
    number = 1234567
    brain.print("Formatted: ")
    brain.new_line()
    brain.print("{:,}".format(number))
    # Output: Formatted: 1,234,567

# VR threads — Do not delete
vr_thread(main)

Percentage #

:.x% formats decimal values as percentages.

Usage:
:.x%

Parameters	Description
`x`	The amount of decimal places to show.

def main():
    # Display a converted decimal to a percentage
    value = 0.875
    brain.print("Score: {:.1%}".format(value))
    # Output: Score: 87.5%

# VR threads — Do not delete
vr_thread(main)

Hexadecimal #

:#x converts numbers to hexadecimal.

Usage:
:#x

Parameters	Description
	This format specifier has no parameters.

def main():
    # Convert 255 to hexadecimal
    number = 255
    brain.print("Hex: {:#x}".format(number))
    # Output: Hex: 0xff

# VR threads — Do not delete
vr_thread(main)

Binary #

:b converts numbers to binary (base 2).

Usage:
:b

Parameters	Description
	This format specifier has no parameters.

def main():
    # Convert 3 to binary
    brain.print("Binary: {:b}".format(3))
    # Output: Binary: 11

# VR threads — Do not delete
vr_thread(main)

Combining Strings #

You can combine (or concatenate) strings using two approaches:

Using .format #

Insert values directly into the string using {}.

def main():
    # Display an answer based on the given emotion
    emotion = "good"
    brain.print("I'm {}, you?".format(emotion))

# VR threads — Do not delete
vr_thread(main)

+ Operator #

Join multiple parts by using +.

Note: Non-strings must first be converted to strings using str().

def main():
    # Display the x and y values
    x = 10
    y = 20
    brain.print("X: " + str(x) + ", Y: " + str(y))

# VR threads — Do not delete
vr_thread(main)

String Methods #

Python provides built-in methods for modifying and checking strings.

upper #

upper converts all letters in a string to uppercase.

Usage:
upper()

Parameters	Description
	This method has no parameters.

def main():
    message = "vexcode"
    brain.print(message.upper())  # Output: VEXCODE

# VR threads — Do not delete
vr_thread(main)

lower #

lower converts all letters in a string to lowercase.

Usage:
lower()

Parameters	Description
	This method has no parameters.

def main():
    message = "VEXCODE"
    brain.print(message.lower())  # Output: vexcode

# VR threads — Do not delete
vr_thread(main)

Checking for Substrings #

in #

in is a keyword that returns a Boolean indicating whether a word exists in a string.

True - The word exists in the string.
False - The word does not exist in the string.

def main():
    message = "Hey everyone!"
    if "Hey" in message:
        brain.print("Hello!")

# VR threads — Do not delete
vr_thread(main)

startswith #

startswith returns a Boolean indicating whether a string begins with a given value.

True - The word starts the string.
False - The word does not start the string.

Usage:
startswith(substring)

Parameters	Description
`substring`	The substring to check inside the string.

def main():
    message = "VR Robot"

    if message.startswith("VR"):
        brain.print("VR first!")

# VR threads — Do not delete
vr_thread(main)

endswith #

endswith returns a Boolean indicating whether a string ends with a given value.

True - The word ends the string.
False - The word does not end the string.

Usage:
startswith(substring)

Parameters	Description
`substring`	The substring to check inside the string.

def main():
    message = "VR Robot"

    if message.endswith("Robot"):
        brain.print("Robot last!")

# VR threads — Do not delete
vr_thread(main)

Escape Sequences #

Escape sequences are special characters used inside strings to format text output. They are only available for use with the Console.

New Line #

\n moves text to a new line when printing.

def main():
    # Display text on two lines
    brain.print("First line\nSecond line")

# VR threads — Do not delete
vr_thread(main)

Tab Spacing #

\t inserts a tab space between words or numbers,

def main():
    # Display the quantity of barrels
    quantity = 2
    brain.print("Boxes:\t", quantity)

# VR threads — Do not delete
vr_thread(main)