## What is differences between primary actions and secondary actions for checkbox?

While reading material design, i found that i didn’t know the difference between primary and secondary actions. I think it’s too basic, I can’t find any information about it. What is the difference between them especially in check boxes? and can i get some example about it..?

## What is the difference between accessible, accessibilityLabel and accessibilityHint of Text component in react native?

What is the difference between accessible, accessibilityLabel and accessibilityHint of Text component in react native? The react native documentation is not enough to understand. Examples will be more appreciated.

## Linear relations between volume of a polytope and its faces

Let $$P$$ be a polytope. Is anything known about the set of linear relations that hold between the volumes of the (not-necessarily proper) faces of $$P$$ as $$P$$ “varies slightly”? By varies slightly I mean without changing the face lattice—so, it makes sense for a linear functional to vanish at each vector $$(vol(F))_{F \text{ a face of }P’}$$ for $$P’$$ “close” to $$P$$.

## Bluetooth between iPad Mini and Mac Pro keeps dropping

• Mac Pro (early 2009) 4,1 -> 5,1
• macOS 10.14.1 Mojave (using dosdude1.com/mojave)
• iOS 12.1

Hello, I am trying to connect my newly bought (but second hand) iPad to my Mac Pro using bluetooth so that I can take advantage of the Universal Clipboard facility. However, as soon as I pair the iPad and the Mac Pro, the connection drops after a second or so. It doesn’t even allow me time to investigate the RSSI settings.

I know that the bluetooth on the Mac Pro is working because I am using a Magic Keyboard connected by bluetooth with no problems whatsoever.

Thoughts anyone?

## Add custom category name as data-filter to switch between these categories

I have a portfolio page where I would like to place three buttons that will switch between different categories. I am using data-filer to sort them into different projects. I am thinking, how can I give this data-filter a category name, so it would switch depending what category and also when adding new post (project) and using any custom category, it would place it right in that portfolio section.

<?php  get_header(); ?>   <div class="container projects-container">  <div class="gallery-nav" align="center">    <button class="btn btn-default filter-button gallery-link" data-filter="all">All</button>    <button class="btn btn-default filter-button gallery-link" data-filter="architecture">Architecture</button>    <button class="btn btn-default filter-button gallery-link" data-filter="furniture">Furniture</button>   </div>   <div class="row">    <?php    $subs = new WP_Query( array( 'post_parent' =>$  post->post,        'post_type' => 'post',        'meta_key' => '_thumbnail_id'      )   );   if( $subs->have_posts() ) : while($  subs->have_posts() ) :        $subs->the_post(); ?> <div class="col-sm-12 col-md-6 col-lg-4 cover-img filter"> <a href="<?php the_permalink(); ?>"> <?php the_post_thumbnail('post-thumbnail', ['class' => 'img-fluid']); ?></a> </div> <?php endwhile; ?> <?php endif; ?> <?php get_footer();  And this jQuery code: jQuery(document).ready(function(){$  (".filter-button").click(function(){       var value = $(this).attr('data-filter'); if(value == "all") {$  ('.filter').show('1000');       }       else       {          $(".filter").not('.'+value).hide('3000');$  ('.filter').filter('.'+value).show('3000');        }   });    if ($(".filter-button").removeClass("active")) {$  (this).removeClass("active");    }    \$  (this).addClass("active");  }); 

## Is there any difference between these two solutions for finding generating function?

Consider the following question.

Find the generating function for the number of integer solutions to the equation $$c_{1}+c_{2}+c_{3}+c_{4}=20$$ where $$-3\leq c_{1}, -3 \leq c_{2}, -5\leq c_{3}\leq 5,$$ and $$0 \leq c_{4}$$.

• The first solution: $$(c_{1} + 3)+(c_{2}+3)+(c_{3}+5)+c_{4}=20 + 3 + 3 + 5 \Rightarrow c_{1}’+c_{2}’+c_{3}’+c_{4}’=31$$ where $$0\leq c_{1}’, 0 \leq c_{2}’, 0\leq c_{3}’\leq 10,$$ and $$0 \leq c_{4}’$$. The generation function is $$f(x) = (x^{0}+x^{1}+…)^{3}(x^{0}+x^{1}+…+x^{10})$$, and the number of integer solutions is the coefficient of $$x^{31}$$ in $$f(x)$$.

• The second solution (My solution): $$g(x) = (x^{-3}+x^{-2}+…+x^{3})^{2}(x^{-5}+x^{-4}+…+x^{5})(x^{0}+x^{1}+…)$$, and the number of integer solutions is the coefficient of $$x^{20}$$ in $$g(x)$$.

My question: In the solution manual book, the presented solution is the first solution, but I think that the second solution is correct, and it is simpler than the first solution. Is my solution correct? What is the difference between these two solutions?