frexp(n)

✨ frexp(n) — Tcl Float Decomposition ✨

okay bestie, welcome to the frexp(n) page 💖 this one's a lil Tcl math girly and she's honestly so useful once you get her vibe.

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🌸 NAME 🌸

frexp — split a floating-point number into fraction and exponent parts 🎀

✨ SYNOPSIS ✨

package require tcl 9.1

frexp value

like, yes, she needs tcl 9.1 — no skipping that part, bestie 🫶

💅 DESCRIPTION 💅

so the frexp command takes a floating-point number, value, and hands you back a list of two values. yes, a list. two whole elements. slay.

• the first element of the result is the fractional part of value — and she's signed, with a magnitude between 0.5 and 1.0
• the second element of the result is the integer exponent from value

and literally when value is infinite, the fraction is also infinite, of the same sign 🔥 no cap. that's just how she moves.

🦋 EXAMPLE 🦋

the frexp command is paired with the ldexp function, like this:

set value 123.456
lassign [frexp $value] frac exp
set recovered [expr { ldexp($frac, $exp) }]
puts "$value -> $frac*2**$exp -> $recovered"
#       123.456 -> 0.9645*2**7 -> 123.456

the way that 123.456 comes back around to 123.456 — we love a full-circle moment 😭💖

👑 SEE ALSO 👑

• expr(n)
• mathfunc(n)
• modf(n)

go read those too, iykyk 💜

🌈 KEYWORDS 🌈

floating point

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and that's the tea 🍓 this page is from Tcl, version 9.1, under the frexp(n) manual section — cute little math page, iconic behavior, periodt 💅✨