lis_array_axpyz(3f)

✨ lis_array_axpyz — the "add two vectors but make one of them ✨spicy✨" function 💅

okay bestie, so you know how lis(3f) has a whole lil family of array math routines? this is one of them, and she is lowkey iconic. the manual page calls herself lis_array_axpyz(3f), and she lives in the Lis Library Functions section. very demure, very mindful. let's get into it 🫶

🌸 SYNOPSIS 🌸

subroutine lis_array_axpyz(LIS_INTEGER n, LIS_SCALAR alpha, LIS_SCALAR
x(), LIS_SCALAR y(), LIS_SCALAR z(), LIS_INTEGER ierr);

that's the whole signature, no cap. six arguments, one ierr for the drama (we'll get to her) 💀

💖 DESCRIPTION 💖

she calculates the sum of the vectors. that's it, that's the job. the formula is giving:

z = alpha * x + y

so basically: take vector x, glow it up by multiplying by the scalar alpha, then toss vector y on top. the result lands in z. it's the classic axpy move but with a z on the end to catch the output — hence the extra letter, iykyk 🌈

🎀 INPUT 🎀

• n — the size of the vectors. like, how many entries are we even working with, bestie 🦋
• alpha — the scalar value. she's the multiplier, the main character energy that scales x up (or down, or to zero, we don't judge) 💅
• x, y — the arrays that store the vectors. these two are the besties going in 🫶

⭐ OUTPUT ⭐

• z — and out comes alpha * x + y. periodt. that's the result array, freshly served 🌸

also there's that ierr argument chillin' in the signature — she's the integer error flag, so keep an eye on her after the call, fr fr 👀

👑 SEE ALSO 👑

• lis(3)
• http://www.ssisc.org/lis/

go poke around the site, the whole library is there and she's thriving ✨

and that's the page, bestie!! this lil writeup came from the Lis Library Functions source, dated 3 Dec 2014, and the original footer tagged it as the man page for lis_array_axpyz(3f). go forth and axpyz responsibly 💖🦋🎀