Databases
StackOverflow2013
Postsdbo
POc++ working with 2d arrays
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POc++ working with 2d arrays
    primarykey
    data
    text
    <p>Currently I'm learning C++ and I've been trying to create a simple image processing library for learning purposes.</p> <p>One of my features is eroding an image. As input it has two 2d arrays, and it returns another 2d array. All these arrays are of variable size. Let's give you an example of what I want to achieve.</p> <pre><code>int image[5][5] = { {'0', '0', '0', '0','0'}, {'0', '1', '1', '1','0'}, {'0', '0', '1', '0','0'}, {'0', '1', '1', '1','0'}, {'0', '0', '1', '0','0'}, }; int kernel[3][3] = { {'0', '1', '0'}, {'1', '1', '1'}, {'0', '1', '0'}, }; </code></pre> <p>Then I want to pass them to my function (this doesn't compile, but it serves as an example of what I want).</p> <pre><code>int** erode(int image[][], int kernel[][]); </code></pre> <p>So far, I've read quite a bit about this. All I've read is that the columns can be of variable length, but the rows can't. So I should be change it to the following:</p> <pre><code>int** erode(int image[][5], int kernel[][3]); </code></pre> <p>But that's not really want I want either, because well, the image can be 10*10 and the kernel could be 5*5. So this isn't optimal in this situation either.</p> <p>Then what I've read is creating a class, that internally stores the image as a 1d array and makes it look like a 2d array. Also I've read about using the <code>Boost.MultiArray</code> class to do this. But well I'm not too happy about that either. Because then I'm forcing the people that use it to also use those classes. And I think it's creating a lot of complexity for something that seems really simple (at least it is in C#)</p> <p>To be honest, I can't imagine there isn't an easier way to do this. Optimally I'd say only use classes/methods from the standard <code>C++11</code> library. <strong>How would you solve this problem?</strong></p> <p>Timo</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USTimo Willemsen
    plurals
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POc++ working with 2d arrays
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POc++ working with 2d arrays
      1. USSoftware_Designer
      1. VTFavorite
    1. COwhats wrong with boost?
      singulars
      1. POc++ working with 2d arrays
      1. USAnycorn
    2. COI guess nothing, but I was wondering if it couldn't be done without using external libraries. I guess it's also better for my understanding of pointers and arrays in C++ if I did it myself.
      singulars
      1. POc++ working with 2d arrays
      1. USTimo Willemsen
    3. COyou can find multiple examples on SO, search for `c++ matrix class`. eg: http://stackoverflow.com/questions/5633609/c-matrix-class-suggestions
      singulars
      1. POc++ working with 2d arrays
      1. USAnycorn
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload