PLSURF3DL(3plplot)

💅 PLSURF3DL — plot a shaded 3-d surface, but make it lopsided 💅

okay so bestie, this is a PLplot API page (3plplot), and we're talking about the plsurf3dl function. Buckle up, she's a little extra but she's iconic.

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✨ NAME ✨

plsurf3dl — plot a shaded 3-d surface plot for z[x][y] with y index limits. yes, "3-d", she's got depth, literally.

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🎀 SYNOPSIS 🎀

plsurf3dl(x, y, z, nx, ny, opt, clevel, nlevel, indexxmin, indexxmax,
indexymin, indexymax)

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🌸 DESCRIPTION 🌸

So basically this is a variant of plsurf3d(3plplot) — go read that function's docs for the full tea, because there's more detail over there 🫶. But plsurf3dl is the one you want when the area of the x, y coordinate grid where z is defined can be non-rectangular. Like, the grid isn't a nice lil rectangle, it's shaped. And that's fine! She's got range 💅.

The limits of that grid are handed to you by the parameters indexxmin, indexxmax, indexymin, and indexymax. That's the whole personality.

Redacted form (the shorter vibe): plsurf3dl(x, y, z, opt, clevel, indexxmin, indexymin, indexymax)

This function is used in example 8. go look, it's cute ✨

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🦋 ARGUMENTS 🦋

• x (PLFLT_VECTOR(3plplot), input) — A vector containing the x coordinates at which the function is evaluated.
• y (PLFLT_VECTOR(3plplot), input) — A vector containing the y coordinates at which the function is evaluated.
• z (PLFLT_MATRIX(3plplot), input) — A matrix containing function values to plot. Should have dimensions of nx by ny. the actual content, the star of the show 💖
• nx (PLINT(3plplot), input) — Number of x values at which function is evaluated.
• ny (PLINT(3plplot), input) — Number of y values at which function is evaluated.
• opt (PLINT(3plplot), input) — Determines the way in which the surface is represented. To specify more than one option just add the options, e.g. FACETED + SURF_CONT. And here's the whole menu, bestie:
  • opt=FACETED : Network of lines is drawn connecting points at which function is defined.
  • opt=BASE_CONT : A contour plot is drawn at the base XY plane using parameters nlevel and clevel.
  • opt=SURF_CONT : A contour plot is drawn at the surface plane using parameters nlevel and clevel.
  • opt=DRAW_SIDES : draws a curtain between the base XY plane and the borders of the plotted function.
  • opt=MAG_COLOR : the surface is colored according to the value of Z; if MAG_COLOR is not used, then the surface is colored according to the intensity of the reflected light in the surface from a light source whose position is set using pllightsource(3plplot). lowkey a whole lighting setup, she's got a glam team 🧚
• clevel (PLFLT_VECTOR(3plplot), input) — A vector containing the contour levels.
• nlevel (PLINT(3plplot), input) — Number of elements in the clevel vector.
• indexxmin (PLINT(3plplot), input) — The index value (which must be ≥ 0) that corresponds to the first x index where z is defined. no negatives, periodt.
• indexxmax (PLINT(3plplot), input) — The index value (which must be ≤ nx) which corresponds (by convention) to one more than the last x index value where z is defined. yeah, "one more than the last" is just how she rolls 🙈
• indexymin (PLINT_VECTOR(3plplot), input) — A vector containing the y index values which all must be ≥ 0. These values are the first y index where z is defined for a particular x index in the range from indexxmin to indexxmax - 1. The dimension of indexymin is indexxmax.
• indexymax (PLINT_VECTOR(3plplot), input) — A vector containing the y index values which all must be ≤ ny. These values correspond (by convention) to one more than the last y index where z is defined for a particular x index in the range from indexxmin to indexxmax - 1. The dimension of indexymax is indexxmax.

⚠️ note the bounds, bestie: indexxmin ≥ 0, indexxmax ≤ nx, indexymin values ≥ 0, indexymax values ≤ ny. don't come for me if you ignore these, that's on you 💀

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👑 AUTHORS 👑

Many developers (who are credited at http://plplot.sourceforge.net/credits.php) have contributed to PLplot over its long history. a whole squad, honestly, legends only 🌈

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⭐ SEE ALSO ⭐

PLplot documentation at http://plplot.sourceforge.net/documentation.php. go read, it's giving educational 💜

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that's the whole page, no cap ✨ mwah 💋 — page PLSURF3DL(3plplot), from the PLplot API, dated August, 2026. bye bestie, slay your surface plots 🎀🦋