NAME

Tk::LogScale - A logarithmic Scale widget

SYNOPSIS

  use Tk::LogScale;
  $scale = $mw->LogScale(...);

DESCRIPTION

This is a Scale widget which uses a logarithmic scale for the position of the thumb.

OPTIONS

Tk::LogScale roughly uses the same options as in Tk::Scale. The -digits option is not implemented. For the -bigincrement and -resolution, translated values have to be used. The -variable option can only be used if the Tie::Watch module is installed (Note: Tie::Watch is in the Perl/Tk distribution since 800.022).

The following options are new to Tk::LogScale:

-func

Function to translate from real values to internal scale values. By default this is the log function. If you want the 10-log, you can set this option to sub { log($_[0])/log(10) }

-invfunc

This should be the inverse function of -func. By default this is the exp function. For 10-log, use sub { 10**$_[0] }

-valuefmt

Callback to format the value for -showvalue. The default is to show integer values.

ADVERTISED SUBWIDGETS

scale

The scale widget.

dummy

A dummy placeholder for the showvalue area.

showvalue

A label holding the current value of the scale. This one is placed over/left to the thumb of the scale.

BUGS

Multiple ties of the same variable specified in -variable will lead to unpredictable results.

There are still some unimplemented options.

The correct implementation of the -bigincrement, -resolution and -tickinterval options is unclear.

AUTHOR

Slaven Rezic <slaven@rezic.de>

SEE ALSO

Tk::Scale, Tie::Watch.