Multidimensional ArrayAccess in PHP is impossible

I’m working on NumPHP again and for the next version I would like to give this library a little bit more syntactic sugar. For example the get and set functions look like this at the moment.

$column = $matrix->get('1:3', 5);
$matrix->set(3, '1:', $vector);

Not bad, but something like this would be better.

$column = $matrix['1:3'][5];
$matrix[3]['1:'] = $vector;

So I have found the interface ArrayAccess, but it has one big problem. It is not for multidimensional objects.

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Disable clickable links in WordPress comments

I have noticed more and more links to commercial Magento extensions in the comments of my blog. That is pretty normal, cause my Magento extensions aren’t free of conflicts with other extensions and people just want to give me a hint. But sometimes I’m not sure if they just want to ask a stupid question and make their link. SEO isn’t my hot topic. Everything I know is, good content and backlinks are important. I always visit the website of an comment and sometimes I remove their link to an commercial Magento extension shop. But I would like to disable the links in the comments. So I have decided to make all links in comments not clickable.

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Cholesky decomposition in PHP with NumPHP

Today I have released NumPHP 1.0.2. I have added the Cholesky decomposition. It factors a matrix into a lower and a upper triangular matrix like the LU Decomposition. The disadvantage is, the Cholesky decomposition works only for symmetric positive definite matrices. The advantage is, it is faster than the LU decomposition and the resulting matrices are L (lower triangular) and LT (transposed of L, upper triangular). This can be helpful to solve systems of linear equations with symmetric positive definite matrices faster.

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Solving a linear system in PHP with NumPHP

I would like to show, how to solve a system of linear equations in PHP with NumPHP.

What is NumPHP?

NumPHP is my pretty small library in pre development status. I have build it after using Numpy in the university. I have missed some features like the multiplication of matrices in PHP. Sure, PHP is a language for the web and not for science, but sometimes it can be very helpful to solve problems with the calculation of matrices. Numpy can do a lot more and NumPHP hasn’t the claim to be used for science, but maybe it can be helpful to solve little problems on a webpage or to evaluate some user datas. I have called the current status pre developer, cause I just wanted to check if it would be possible and I just have implemented the most important functions for this little example. NumPHP is completely tested. Enough excuses.

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Mage Unconference 2015

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Since two years I wasn’t on any magento confernce. That’s mostly because I’m a student and I haven’t enough money for big conferences. So today I would like to promote the Mage Unconference 2015 and this post is my contribution. The conference will happen at 7th and 8th March 2015 in Berlin. I have my ticket and it would be pretty cool to meet some people from the magento community, that I only know from there github avatars.