Expanded use of traits? about math-php HOT 6 CLOSED

Cool. I think I get it.

My one concern is that since it would be using an ordered numerical array, it is easy to mess up parameters and it isn't immediately clear what is going on. So I'd want LinearModel etc. to have parameter constants:

const X = 0; // x parameter index
const M = 1; // m parameter index
const B = 2; // b parameter index

Something like that, so then you can do:

    function evaluateModel(...$params)
    {
        $x = $params[self::X];
        $m = $params[self::M];
        $b = $params[self::B];
        return $m * $x + $b;
    }

Basically, outside of a loop, if you are indexing into a numerical array, you probably want to do it with named meaningful constants to increase code clarity.
Thanks.

from math-php.

I agree with the naming. However, in the case linear or polynomial, the evaluate function is easily calculated using:

// $order = 1 for linear, 2 for y=m1 * x²+m2 * x +b, 3 for x^3, etc.
return Vandermonde($x, $order + 1)->multiply($betas)[0][0];

from math-php.

I have something in the works in my repository, but I'm seeing errors like the following:

1. Math\Statistics\Regression\HanesWoolfTest::testGetParameters with data set #0 (array(array(0.037999999999999999, 0.050000000000000003), array(0.19400000000000001, 0.127), array(0.42499999999999999, 0.094), array(0.626, 0.2122), array(1.2529999999999999, 0.27289999999999998), array(2.5, 0.26650000000000001), array(3.7400000000000002, 0.33169999999999999)), 0.36151233700000002, 0.55417895500000003)
   Error: Call to undefined method Math\Statistics\Regression\Regression::getModelParameters()
   /home/travis/build/Beakerboy/math-php/src/Statistics/Regression/Regression.php:83
   /home/travis/build/Beakerboy/math-php/tests/Statistics/Regression/HanesWoolfTest.php:13

Any ideas? Is there "one simple trick" to getting static methods to work in traits?

from math-php.

Static trait methods should work. Since you are inheriting from a parent Regression class, and that is making the call, but that doesn't have the trait, then that could be the cause of the method not being defined. I think if you include the use trait in the parent Regression class it will work, but then that kind of defeats the point of what you are trying to do.
The issue seems to be whether a parent method can use a child's trait, which might be no, but I'm not 100% sure.

from math-php.

Maybe using get_called_class() (or whatever that function is called) will work.

from math-php.

I've submitted a pull request. Lots has changed, but going forward I think this will make things more flexible and easier to extend.

from math-php.