====== Template Helper Functions ======

Helper functions are meant to simplify the creation of templates and trap errors

===== rrd::def =====

string **rrd::def** ( $vname, $rrdfile, $ds, [ $cf='AVERAGE' ] )

<code php>
$def = rrd::def('var1', $RRDFILE[0], $DS[0], 'MAX'); 
</code>

http://oss.oetiker.ch/rrdtool/doc/rrdgraph_data.en.html

===== rrd::cdef =====

string **rrd::cdef** ( $vname, $rpn, )

<code php>
$def = rrd::cdef('var1_bits', 'var1,8,*' ); 
</code>

http://oss.oetiker.ch/rrdtool/doc/rrdgraph_data.en.html

===== rrd::vdef =====

string **rrd::vdef** ( $vname, $rpn, )

<code php>
$def = rrd::vdef('var1_avg', 'var1,AVERAGE' ); 
</code>

http://oss.oetiker.ch/rrdtool/doc/rrdgraph_data.en.html

===== rrd::line[1-3] =====

string **rrd::line[1-3]** ( $vname, $color, [ $text ], [ $stack ] )

<code php>
$def .= rrd::line1('var1', #ff00ff ); 
</code>

Draws a simple line one pixel wide without label

<code php>
$def .= rrd::line3('var1', '#ff00ff', 'Load' ); 
</code>

Draws a line three pixels wide with label "Load"

http://oss.oetiker.ch/rrdtool/doc/rrdgraph_graph.en.html

===== rrd::area =====

string **rrd::area** ( $vname, $color, [ $text ], [ $stack ] )

<code php>
$def .= rrd::area('var1', '#ff00ff', 'Load' ); 
</code>

Draws an area with label "Load"

http://oss.oetiker.ch/rrdtool/doc/rrdgraph_graph.en.html

===== rrd::gprint =====

string **rrd::gprint** ( $vname, $cf, [ $text ] )

<code php>
$def .= rrd::gprint('var1', 'MAX', '%4.2lf %s Max' ); 
</code>

<code php>
$def .= rrd::gprint('var1', array('MIN', 'MAX', 'AVERAGE'), '%4.2lf %s' ); 
</code>

If $cf is an array the legend will be formatted automatically

http://oss.oetiker.ch/rrdtool/doc/rrdgraph_graph.en.html

===== rrd::color =====

string **rrd::color** ( $num [, $num])

Returns a color from the HTML color table. The second (optional) argument allows to specify an alpha value used to set the transparency of the selected color.

===== rrd::gradient =====

string **rrd::gradient** ( $vname, [$start_color], [$end_color], [$label], [$steps], [$lower] )

Creates a color gradient from $start_color to $end_color

<code php>
$def .= rrd::gradient('var1', '#ff0000', '#ffff00' ); 
</code>
[[templates:gradient|Example]]

===== rrd::cut =====

string **rrd::cut** ( $text, $length )

<code php>
$label = rrd::cut($LABEL[0], 18); 
</code>

Cuts a text to a given length $length or fills it up to $length if needed.\\ 
This function is helpful if legend needs to be justified but length of label is unknown.

===== rrd::ticker =====

string **rrd::ticker** ( $vname, $warning, $critical, [$fraction], [$opacity], [$color_OK], [$color_WARN], [$color_CRIT] )

Creates a colorized bar at the top of the chart which shows different colors depending on states OK, WARNING & CRITICAL

<code php>
$def .= rrd::ticker( "var1", $WARN[0], $CRIT[0] );

</code>
[[templates:ticker|Example]]

===== rrd::alerter =====

string **rrd::alerter** ( $vname, $label, $warning, $critical, [$opacity], [$unit], [$color_OK], [$color_WARN], [$color_CRIT], [$line_col] )

Creates colorized areas, which show different colors depending on states OK, WARNING & CRITICAL

<code php>
$def .= rrd::alerter( "var1", $LABEL[0], $WARN[0], $CRIT[0], "FF", $UNIT[0] );
</code>

[[templates:alerter|Example]]

===== rrd::alerter_gr =====

string **rrd::alerter_gr** ( $vname, $label, $warning, $critical, [$opacity], [$unit], [$color_OK], [$color_WARN], [$color_CRIT], [$line_col], [$start_color] )

Creates colorized gradients, which show different colors depending on states OK, WARNING & CRITICAL

<code php>
$def .= rrd::alerter_gr( "var1", $LABEL[0], $WARN[0], $CRIT[0], "FF", $UNIT[0] );
</code>

[[templates:alerter_gr|Example]]