Math::PlanePath::File3pm

Usage

 use Math::PlanePath::File;
 my $path = Math::PlanePath::File->new (filename => 'foo.txt');
 my ($x, $y) = $path->n_to_xy (123);

Overview

This path reads X,Y points from a file to present in PlanePath style. It's slightly preliminary yet but is handy to get numbers from elsewhere into a PlanePath program.

The intention is to be flexible about the file format and to auto-detect as far as possible. Currently the only format is plain text, with an X,Y pair, or N,X,Y triplet on each line

    5,6                   # X,Y
    123  5 6              # N,X,Y

Numbers can be separated by a comma or just spaces and tabs. Lines not starting with a number are ignored as comments (or blanks). N values must be integers, but the X,Y values can be fractions like 1.5 too, including exponential floating point 1500.5e-1 etc.

Functions

See "FUNCTIONS" in Math::PlanePath for behaviour common to all path classes.

"$path = Math::PlanePath::File->new (filename => "/my/file/name.txt")"

Create and return a new path object.

"($x,$y) = $path->n_to_xy ($n)"

Return the X,Y coordinates of point number $n on the path.

"$n = $path->xy_to_n ($x,$y)"

Return the point number for coordinates "$x,$y".

In the current code an "$x,$y" within a unit circle or square of a point from the file gives that point. But perhaps in the future some attention could be paid to apparent spacing of points closer than that.

"$bool = $path->x_negative()"

"$bool = $path->y_negative()"

Return true if there are any negative X or negative Y coordinates in the file.

"$n = $path->n_start()"

Return the first N in the path. For files of just X,Y points the start is N=1, for N,X,Y data it's the first N.

"$str = $path->figure()"

Return a string name of the figure (shape) intended to be drawn at each $n position. In the current code if all X,Y are integers then this is "square", otherwise it's "circle". But perhaps that will change.

Home page

<http://user42.tuxfamily.org/math-planepath/index.html>