TikZImages

Graphic Images, TikZImages

This example shows how to create an image/plot using Tikz.

Problem Techniques Index

PG problem file	Explanation
DOCUMENT(); loadMacros( "PGstandard.pl", "MathObjects.pl", "PGML.pl", "PGtikz.pl" ); TEXT(beginproblem());	Initialization: It is important to include the PGtikz.pl macro.
$graph_image = createTikZImage(); $graph_image->tikzLibraries("arrows.meta"); # Randomization $a = non_zero_random(-6,6); # horizonatal translation $b = random(-4,4); # vertical translation $graph_image->BEGIN_TIKZ \draw[<->,thick] (-11,0) -- (11,0) node[above left,outer sep=2pt]{\(x\)}; \draw[<->,thick] (0,-11) -- (0,11) node[below right,outer sep=2pt]{\(y\)}; \foreach \x in {-10,-8,...,-2,2,4,...,10} \draw[thin] (\x,5pt) -- (\x,-5pt) node[below]{\(\x\)}; \foreach \y in {-10,-8,...,-2,2,4,...,10} \draw[thin] (5pt,\y) -- (-5pt,\y) node[left]{\(\y\)}; \draw[<->,red] plot[domain={-3.2+$a}:{3.2+$a}] (\x,{pow(\x-$a,2)+$b}); END_TIKZ	Setup: The createTikZImage() function creates an image to be built using tikz. By default an 'svg' image will be generated, which will generally look better than a 'png image. In certain cases the 'svg' creation methods do not give the correct output, and so in those cases a 'png' image may be generated instead by adding $graph_image->ext('png');. The $graph_image->tikzLibraries("arrows.meta"); will load the arrows.meta Tikz library. pg variables $a and $b are defined for use in the TikZ code that follows. If the TikZ code references non-existent pg variables the image creation fails silently. The actual tikz image is built between $graph_image->BEGIN_TIKZ and END_TIKZ
BEGIN_PGML [@ image($graph_image, width => 300, tex_size => 1000) @]* END_PGML	Main Text: This is how to insert the tikz image. Note the width and tex_size parameters can change the size of the image on the web and as hardcopy. Note that you may want to call $image = image($graph_image, width => 300, tex_size => 1000) above and use [@ $image @]* here while developing the problem. If the image call occurs inside the BEGIN_PGML/END_PGML section, then you will not get the warnings from failed image generation. You will instead get no image, and no reason as to why.
ENDDOCUMENT();	This doesn't have a question, so we aren't checking an answer.

Problem Techniques Index

• POD documentation: PGtikz.pl
• PG macro: PGtikz.pl