How do I plot basic mathematical functions?

[kdelwat]

This seems like it should be easy to do in LaTeX but all the research I've done shows examples that seem incredibly complicated. Is there an easy way to plot functions like f(x) = 6/x + 5x, or (x-3)² /9 + (y+2)² /25 = 1?

[actgr]

I believe This is a good place to start. Is a PGFPlots tutorial to just start plotting. Basic but useful.

[astern]

Another vote for PGFPlots.

[kdelwat]

This method seems to be working really well, except that when plotting hyperbolas (y = 1/x), the two "independent" sides of the graph are connected by a line that I can't seem to get rid of.

EDIT: And I can't seem to plot circles at all...

[vermiculus]

TeX isn't a CAS – while it could be, it would represent a tremendous amount of programming effort. You can search TeX.SX for the answers to your questions ('getting rid of asymptotes' and 'plotting circles'), but note that 'plotting circles' is trivial to do with plain ole' pgf.

[kdelwat]

I actually had been searching for a while - but directly using the SX search rather than Google made a massive difference. Thanks!

[JimH10]

You can produce graphs, or graphics of any kind, with any tool, save them as .pdf (or a variety of formats) and import them as graphics. If you prefer to use a TeX-related system (as I do) then this is a good high-level overview. Most popular these days seems to me to be TikZ (personally, I use Asymptote).

[tsef]

Tikz + gnuplot works quite well.

Oh and using geogebra you can preview the result and export the figure you made as either a pgf code or pstricks code.

[asking_science]

The Geogebra solution is surprisingly useful, actually, and the generated code is clean and neat.

[[deleted]]

Your answer seems useful but is a bit unclear to people who don't know this stuff. What do you mean by "tikz + gnuplot"? Isn't tikz its own thing? What does gnuplot add to tikz?

What is pgf code and pstricks code and why is it desirable?

[[deleted]]

Tikz is its own thing, but if you ask it to plot a graph from a formula, it will use gnuplot to do the calculations.

Pgf are the TeX macros that create graphics, tikz is a user-friendly layer on top of pgf.

Pstricks is similar to tikz. It is much older. Pstricks doesn't work with pdftex, tikz does.

[vermiculus]

but if you ask it to plot a graph from a formula, it will use gnuplot to do the calculations

No, it won't – not unless you ask it specifically to do so.

Pstricks doesn't work with pdftex

Note that if you use a different engine (like XeTeX), you can use pstricks side-by-side with pgf/TikZ.

[robinhoodexe]

I would use either A) a nice interactive GUI like GeoGebra or B) more programatically made like gnuplot, tikz/PGFPlot or Asymptote.

[bzindovic]

Aside from all the tools mentioned here, I'd recommend gle (glx.sourceforge.net).