Pi (letter)

From Wikipedia, the free encyclopedia

Pi (/ˈpaɪ/; Ancient Greek /piː/ or /peî/, uppercase Π, lowercase π, cursive ϖ; Greek: πι [pi]) is the sixteenth letter of the Greek alphabet, meaning units united, and representing the voiceless bilabial plosive IPA: [p]. In the system of Greek numerals it has a value of 80. It was derived from the Phoenician letter Pe (). Letters that arose from pi include Latin P, Cyrillic Pe (П, п), Coptic pi (Ⲡ, ⲡ), and Gothic pairthra (𐍀).[1]

Uppercase Pi[edit]

The uppercase letter Π is used as a symbol for:

In science and engineering:

Lowercase Pi[edit]

The lowercase letter π is used as a symbol for:

The earliest polyamory pride flag design, created by Jim Evans in 1995, in which the lowercase letter π stands for the first letter of polyamory.

History[edit]

An early form of pi was , appearing almost like a gamma with a hook.[citation needed]

Variant pi[edit]

Variant pi or "pomega" ( or ϖ) is a glyph variant of lowercase pi sometimes used in technical contexts. It resembles a lowercase omega with a macron, though historically it is simply a cursive form of pi, with its legs bent inward to meet. It was also used in the minuscule script. It is a symbol for:

Character encodings[edit]

The various forms of pi are present in Unicode as:

  • U+03A0 Π GREEK CAPITAL LETTER PI (Π)
  • U+03C0 π GREEK SMALL LETTER PI (π)
  • U+03D6 ϖ GREEK PI SYMBOL (ϖ, ϖ)
  • U+220F N-ARY PRODUCT (∏, ∏)
  • U+1D28 GREEK LETTER SMALL CAPITAL PI
  • U+1D70B 𝜋 MATHEMATICAL ITALIC SMALL PI
  • U+1D6D1 𝛑 MATHEMATICAL BOLD SMALL PI.[9]

Character encodings tables[edit]

  • Greek / Coptic Pi[10]


    Character information
    Preview Π π ϖ
    Unicode name GREEK CAPITAL LETTER PI GREEK SMALL LETTER PI GREEK PI SYMBOL COPTIC CAPITAL LETTER PI COPTIC SMALL LETTER PI
    Encodings decimal hex dec hex dec hex dec hex dec hex
    Unicode 928 U+03A0 960 U+03C0 982 U+03D6 11424 U+2CA0 11425 U+2CA1
    UTF-8 206 160 CE A0 207 128 CF 80 207 150 CF 96 226 178 160 E2 B2 A0 226 178 161 E2 B2 A1
    Numeric character reference Π Π π π ϖ ϖ Ⲡ Ⲡ ⲡ ⲡ
    Named character reference Π π ϖ, ϖ
    DOS Greek 143 8F 167 A7
    DOS Greek-2 198 C6 234 EA
    Windows 1253 208 D0 240 F0
    TeX \Pi \pi \varpi
  • Mathematical Pi


    Character information
    Preview 𝚷 𝛑 𝛱 𝜋
    Unicode name N-ARY PRODUCT N-ARY COPRODUCT MATHEMATICAL BOLD
    CAPITAL PI
    MATHEMATICAL BOLD
    SMALL PI
    MATHEMATICAL ITALIC
    CAPITAL PI
    MATHEMATICAL ITALIC
    SMALL PI
    Encodings decimal hex dec hex dec hex dec hex dec hex dec hex
    Unicode 8719 U+220F 8720 U+2210 120503 U+1D6B7 120529 U+1D6D1 120561 U+1D6F1 120587 U+1D70B
    UTF-8 226 136 143 E2 88 8F 226 136 144 E2 88 90 240 157 154 183 F0 9D 9A B7 240 157 155 145 F0 9D 9B 91 240 157 155 177 F0 9D 9B B1 240 157 156 139 F0 9D 9C 8B
    UTF-16 8719 220F 8720 2210 55349 57015 D835 DEB7 55349 57041 D835 DED1 55349 57073 D835 DEF1 55349 57099 D835 DF0B
    Numeric character reference ∏ ∏ ∐ ∐ 𝚷 𝚷 𝛑 𝛑 𝛱 𝛱 𝜋 𝜋
    Named character reference ∏, ∏ ∐, ∐
    TeX \prod \coprod


    Character information
    Preview 𝜫 𝝅 𝝥 𝝿 𝞟 𝞹
    Unicode name MATHEMATICAL BOLD ITALIC
    CAPITAL PI
    MATHEMATICAL BOLD ITALIC
    SMALL PI
    MATHEMATICAL SANS-SERIF
    BOLD CAPITAL PI
    MATHEMATICAL SANS-SERIF
    BOLD SMALL PI
    MATHEMATICAL SANS-SERIF
    BOLD ITALIC CAPITAL PI
    MATHEMATICAL SANS-SERIF
    BOLD ITALIC SMALL PI
    Encodings decimal hex dec hex dec hex dec hex dec hex dec hex
    Unicode 120619 U+1D72B 120645 U+1D745 120677 U+1D765 120703 U+1D77F 120735 U+1D79F 120761 U+1D7B9
    UTF-8 240 157 156 171 F0 9D 9C AB 240 157 157 133 F0 9D 9D 85 240 157 157 165 F0 9D 9D A5 240 157 157 191 F0 9D 9D BF 240 157 158 159 F0 9D 9E 9F 240 157 158 185 F0 9D 9E B9
    UTF-16 55349 57131 D835 DF2B 55349 57157 D835 DF45 55349 57189 D835 DF65 55349 57215 D835 DF7F 55349 57247 D835 DF9F 55349 57273 D835 DFB9
    Numeric character reference 𝜫 𝜫 𝝅 𝝅 𝝥 𝝥 𝝿 𝝿 𝞟 𝞟 𝞹 𝞹


    Character information
    Preview
    Unicode name DOUBLE-STRUCK CAPITAL PI DOUBLE-STRUCK SMALL PI
    Encodings decimal hex dec hex
    Unicode 8511 U+213F 8508 U+213C
    UTF-8 226 132 191 E2 84 BF 226 132 188 E2 84 BC
    Numeric character reference ℿ ℿ ℼ ℼ
    The character encodings in the tables above are intended for use as mathematical symbols. Text written in the Greek language (i.e. words, as opposed to mathematics) should not come from any of the tables on this page, but instead should use the normal Greek letters, which have different code numbers and often a different appearance. Using the mathematical symbols to display words (or vice versa) is likely to result in inconsistent spacing and a clumsy, mismatched appearance.

See also[edit]

References[edit]

  1. ^ "Pi Symbol in Greek Alphabet". greeksymbols.net. Retrieved 2023-02-07.
  2. ^ Thomas, Melody (April 22, 2019). "Pretty poly: Why non-monogamous relationships are all the rage". Archived from the original on February 26, 2021. Retrieved March 24, 2021.
  3. ^ Schumer, Lizz (May 16, 2022). "21 LGBTQ Flags and What They Symbolize". Good Housekeeping.
  4. ^ Walsh, Matthias. "What does the polyamorous flag look like?". LGBTQ Nation.
  5. ^ "Jim Evans' Polyamory Pride Flag". Archived from the original on November 10, 2014.
  6. ^ "Pomega". Eric Weisstein's World of Physics. wolfram.com.
  7. ^ Outline for Weeks 14&15, Astronomy 225 Spring 2008 Archived 2010-06-15 at the Wayback Machine
  8. ^ Kobayashi, Hiroyuki; Takeuchi, Shingo (2019). "Applications of generalized trigonometric functions with two parameters". Communications on Pure & Applied Analysis. 18 (3): 1509. arXiv:1903.07407. doi:10.3934/cpaa.2019072. S2CID 102487670.
  9. ^ "Unicode characters supported by the Calibri font". fileformat.info.
  10. ^ Unicode Code Charts: Greek and Coptic (Range: 0370-03FF)