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right_triangle()

Generate configurable right-angled triangle patterns using characters or numbers.

Overview

The right_triangle() function creates a right-angled triangle of height n with flexible styling options, including:

  • Character or numeric output
  • Left or right alignment
  • Inverted orientation
  • Hollow (border-only) structure
  • Optional spacing for readability

This function is suitable for CLI visualization, pattern generation, and educational demonstrations.

Function Signature

right_triangle(
    n: int,
    char: str = "*",
    alignment: Literal["left", "right"] = "left",
    inversion: bool = False,
    hollow: bool = False,
    numeric: bool = False,
    space: bool = False
) -> str

Parameters

Name Type Default Description
n int — Height of the triangle. Must be positive.
char str "*" Character used to draw the triangle. Ignored if numeric=True.
alignment str "left" Alignment of the triangle: left or right.
inversion bool False If True, generates an inverted triangle.
hollow bool False If True, draws only the border of the triangle.
numeric bool False Uses numbers instead of characters (e.g., 1, 12, 123).
space bool False Adds spaces between elements for better readability.

Returns

  • str — A newline-separated string representing the triangle.

Raises

Exception Condition
ValueError If n <= 0
ValueError If alignment is not "left" or "right"
ValueError If numeric=True and char is specified

Usage

Default Pyramid

*
**
***
****

Usage Example

1. Default Right-Triangle
print(right_triangle(4))

*
**
***
****
2. Right-Triangle (with space=True)
print(right_triangle(4, space=True))

*
* *
* * *
* * * *
3. Right-Triangle (with hollow=True)
print(right_triangle(5, hollow=True))

*
**
* *
*  *
*****
4. Right-Triangle (with hollow=True and space=True)
print(right_triangle(5, hollow=True, space=True))

*
* *
*   *
*     *
* * * * *
5. Right-Triangle (with inversion=True)
print(right_triangle(4, inversion=True))

****
***
**
*
6. Right-Triangle (with inversion=True and space=True)
print(right_triangle(4, inversion=True, space=True))

* * * *
* * *
* *
*
7. Right-Triangle (with inversion=True and hollow=True)
print(right_triangle(5, inversion=True, hollow=True))

*****
*  *
* *
**
*
8. Right-Triangle (with inversion=True and hollow=True and space=True)
print(right_triangle(5, inversion=True, hollow=True, space=True))

* * * * *
*     *
*   *
* *
*

Right-Aligned Triangle

*
**
***
****

Usage Examples

1. Right-Aligned Triangle (alignment=right)
print(right_triangle(4, alignment="right"))

   *
  **
 ***
****
2. Right-Aligned Triangle (alignment=right and space=True)
print(right_triangle(4, alignment="right"))

      *
    * *
  * * *
* * * *
3. Right-Aligned Triangle (alignment=right and hollow=True)
print(right_triangle(5, alignment=True, hollow=True))

    *
  * *
 *  *
*****
4. Right-Aligned Triangle (alignment=right and inversion=True)
print(right_triangle(4, alignment="right", inversion=True))

****
 ***
  **
   *
5. Right-Aligned Triangle (alignment=right and inversion=True and hollow=True)
print(right_triangle(5, alignment="right", inversion=True, hollow=True))

*****
 *  *
  * *
   **
    *

Numeric Right-Triangle

1
12
123
1234

Usage Examples

1. Numeric Triangle (numeric=True)
print(right_triangle(4, numeric=True))

1
12
123
1234
2. Numeric Triangle (numeric=True and space=True)
print(right_triangle(4, numeric=True, space=True))

1
1 2
1 2 3
1 2 3 4
3. Numeric Triangle (numeric=True and hollow=True)
print(right_triangle(5, numeric=True, hollow=True))

1
12
1 3
1  4
12345

More Examples

Example 1
print(right_triangle(4,char="#",space=True))

#
# #
# # #
# # # #
Example 2
print(right_triangle(5,"1",hollow=True))

1
11
1 1
1  1
11111

Warnings

  • Hollow triangles may not render properly for very small sizes (n <= 3)
  • The function prints a warning message in such cases
  • Space option may not work well with right alignment

Notes

  • char is ignored when numeric=True
  • Output is always returned as a string (not printed)
  • Alignment padding is based on n
  • Spacing affects both numeric and character modes

Tips

  • Use space=True for clearer visual output in larger triangles
  • Use right alignment for staircase-style visuals
  • Combine hollow=True with larger n for better patterns
  • Numeric mode is useful for teaching loops and sequences