I'm really not sure exactly what you mean. RGB 'values' contain as many as 4
values (if you include alpha channel). Hence, an RGB value is 3 dimensional
in and of itself. Also, I'm not clear concerning what you mean by
'value(1,2,3,...)'. Do you mean position on the screen? If so, then this too
is multi-dimensional ala (x,y). Therefore from yuor description it sounds
like yuor graph needs to be 5-dimensional, which is of course very hard
'visualize', let alone represent on a 2-dimensional display.

What exactly do you mean by a 'line graph'? I don't want to assume anything
about how you use this term, since from my point of view, ALL graphs can be
drawn as a 'line-graph' (i.e., graphs drawn with lines). To me this is a
style, not a method type.

You know it might be helpful if you described exactly what you are trying to
accomplish (i.e., the 'bigger picture'). Is this for compressing graphic
files? Equalization? That kind of thing.

I think I know what you mean by 'column of values', but I'll ask to be sure.
Do you mean the column has positions (1st, 2nd, 3rd, etc.) and you want to
plot position vs value at that position in the column? That sounds ver much
like a histogram...

Also, what part of the problem do you need help with? The actually drawing
of the graph in VC++? There are no native 'graph methods' I know of, so
whenever I need to draw a graph I write the whole thing myself to custom fit
the project I'm doing. In my case, I manage to draw all graphs using the
Label class as a solid box I can put text in! Note that a thin solid box
without text is a line... :) There are graphic drawing functions in VC++
which you might want to look into, but they require some not-so-obvious
setup (like device contexts and handles).

Finally, I often just use text if the graph needs only to be histogram in
nature. Just use various lengths of asteriks strings to represent graph
extent at each value (the 'y' to the graph's 'x'), and draw these asteriks
strings anchored on the x-axis at its x-value with its length equal to its
y-value (the value's tally count for a histogram). Scaling is easy to make
it fit any size box on the screen you need, depending on how accurate your
graphs must be...

I know this isn't much help, but it is my train of thought on the subject at
hand... :)

[==Peteroid==]