PLIMAGEFR(3plplot)

💖 PLIMAGEFR 💖

okay bestie, buckle up — this is the PLplot API page for plimagefr, and honestly? it's a whole vibe. it plots a 2D matrix using cmap1, and it's lowkey the main character of example 20. let's get into it 🫶

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✨ NAME ✨

plimagefr — plot a 2D matrix using cmap1. that's the whole thing. icon behavior.

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🌸 SYNOPSIS 🌸

plimagefr(idata, nx, ny, xmin, xmax, ymin, ymax, zmin, zmax, valuemin,
valuemax, pltr, pltr_data)

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🦋 DESCRIPTION 🦋

so like — plot a 2D matrix using cmap1. that's the job. 💅

Redacted form, General: plimagefr(idata, xmin, xmax, ymin, ymax, zmin, zmax, valuemin, valuemax, pltr, pltr_data)

and pssst — this function is used in example 20. so if you wanna see it living its best life, go look 👀

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🎀 ARGUMENTS 🎀

bestie, there are a lot of arguments here. we're gonna go through every single one, no skipping, fr fr.

• idata (PLFLT_MATRIX(3plplot), input) — the matrix of values (intensities) you're plotting. it should have dimensions of nx by ny. that's the material. the moment. the data.
• nx, ny (PLINT(3plplot), input) — the dimensions of idata. how big your matrix is, basically. know your size, queen.
• xmin, xmax, ymin, ymax (PLFLT(3plplot), input) — these are explained in the pltr discussion below (scroll down, it's there 💖). heads up though: these only matter for the special case when the callback function pltr is not supplied. so if you're passing a pltr, ngl, these are just sitting there vibing.
• zmin, zmax (PLFLT(3plplot), input) — only data between zmin and zmax (inclusive) gets plotted. everything outside that range? not invited to the party. 🙈
• valuemin, valuemax (PLFLT(3plplot), input) — the minimum and maximum data values used for value-to-color mappings. the rules are:
  • a datum equal to or less than valuemin gets plotted with color 0.0
  • a datum equal to or greater than valuemax gets plotted with color 1.0
  • data between valuemin and valuemax maps linearly to colors in the range (0.0-1.0)

slay. it's giving gradient. 🌈

• pltr (PLTRANSFORM_callback(3plplot), input) — a callback function that defines the transformation between the zero-based indices of the matrix idata and world coordinates.

if pltr is not supplied (like, set to NULL in the C case), then the x indices of idata get mapped to the range xmin through xmax, and the y indices of idata get mapped to the range ymin through ymax. that's the default behavior, and yes, that's where those xmin/xmax/ymin/ymax arguments finally earn their keep.

for the C case, transformation functions are provided right there in the PLplot library:

• pltr0(3plplot) for the identity mapping
• pltr1(3plplot) and pltr2(3plplot) for arbitrary mappings defined by vectors and matrices respectively

in addition, C callback routines for the transformation can be supplied by the user — like the mypltr function in examples/c/x09c.c, which provides a general linear transformation between index coordinates and world coordinates. iconic of it, honestly.

for languages other than C, you should consult the PLplot documentation for the details on how PLTRANSFORM_callback(3plplot) arguments are interfaced. but in general: a particular pattern of callback-associated arguments — such as a tr vector with 6 elements; xg and yg vectors; or xg and yg matrices — are respectively interfaced to a linear-transformation routine similar to the above mypltr function; pltr1(3plplot); and pltr2(3plplot).

furthermore, some of our more sophisticated bindings (see, e.g., the PLplot documentation) support native language callbacks for handling index-to-world-coordinate transformations. examples of these various approaches are given in examples/<language>x09*, examples/<language>x16*, examples/<language>x20*, examples/<language>x21*, and examples/<language>x22*, for all our supported languages. yes, ALL of them. we been busy. 😭🔥

• pltr_data (PLPointer(3plplot), input) — an extra parameter to help pass information to pltr0(3plplot), pltr1(3plplot), pltr2(3plplot), or whatever routine is externally supplied. it's the little messenger bag 🎒 for your callback.

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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. legends, all of them. genuinely. 💜

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⭐ SEE ALSO ⭐

PLplot documentation at http://plplot.sourceforge.net/documentation.php. go read it, bestie, it's good for you.

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quick vibe check reminder: if pltr isn't supplied, those xmin/xmax/ymin/ymax arguments are doing the mapping for you. so don't pass NULL and then wonder why your indices look weird. 💀

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and that's the page!! 🌸 this was the PLplot API doc for plimagefr, dated August, 2026 — go plot something gorgeous with it. mwah 💅💖✨