I'm writing a Python program to display terms from (x + y)^k, but any exponent containing the digit 4 leaves a blank space in the output. Testing showed that the issue seems specific to the Unicode character "⁴" (U+2074), while "⁰", "¹", "²", "³", "⁵", "⁶", "⁷", "⁸", and "⁹" display correctly. Is there something special about superscript 4, or could this be a problem with the terminal, browser, font, or encoding?
3 Answers
If you want to generate exponents programmatically, keep a lookup table for the digits and join the mapped characters. For example, map 0 to ⁰, 1 to ¹, 2 to ², 3 to ³, 4 to ⁴, and so on, then convert each digit of the exponent through that table. This will produce the correct Unicode text, although displaying it still depends on the terminal or font supporting the glyph.
The characters are not all from the same Unicode block. Superscripts 1, 2, and 3 are older Latin characters, while superscript 4 is U+2074, from the Unicode superscript and subscript block. That difference does not make U+2074 invalid; it just means the selected font or terminal may not support it. Check the font and encoding used by the output window.
There is nothing inherently wrong with U+2074. Superscript 4 is a valid Unicode character, and Python can print it normally. The blank is most likely caused by the environment displaying the output—some terminals, fonts, or browser consoles don't have a glyph for that character. It worked correctly in another browser and in a local Mac terminal, which points to a display or font issue rather than a Python problem.
The program may still be receiving and generating the character correctly even if the output area doesn't render it. Restarting the execution environment or testing with a different terminal or computer can sometimes make it appear.
U+2075 and the other characters in that block may happen to be supported by the font, while U+2074 is missing or mapped incorrectly. Trying a font with broad Unicode coverage is a good diagnostic.