Databases
StackOverflow2013
Postsdbo
POMidpoints of matrix rows depending on certain conditions Matlab
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POMidpoints of matrix rows depending on certain conditions Matlab
    primarykey
    data
    text
    <p>I have a matrix A with size 10x100 as shown below. What I want to do is:</p> <ol> <li>I'll work row by row in which for each row I'll check the data of each coloumn in this row</li> <li>Let's say I'm now in the first col cell in the first row. I'll check if the value is zero I'll move to the next col, and so on till I found a col having a non-zero value and save its col number e.g. col 3 "this means that col 1&amp;2 were zeros"</li> <li>Now I'm in the first non zero col in row1, I'll move to the next col till I find a col with zero value. I'll fetch the col just before this zero one which must be a non-zero one and save it. e.g col 7 "this means that col4&amp;5&amp;6 are non-zeros and col8 is zero"</li> <li>Now I want to save the median middle col between this two columns e.g col3 and col7 then the middle col is col5 so I'll save the index row1_col5. if there are two middle values then any of them is fine.</li> <li>I'll then move to the next col till I find a non-zero col "do the same steps from 2-->5" till the first row is finished.</li> <li>Move to the next row and start over again from step 2-->5.</li> <li>There are two rules: -The first one is that I'll get the middle index of non-zero consecutive values only if there is a minimum of 3 non-zero consecutive values, if there are two non-zero consecutive value then the middle will not be calculated -The second one is that if the number of zero consecutive values are less than 3 then they will be ignored and will be considered as non-zero values. e.g in the below example the first row middle values are col5 and col11. In row2 col5 is counted, while no cols in row3 satisfy this conditions , and in row4 col6 or col7 will be counted.</li> <li>After finishing all the rows want to have a vector or array holding the positions of all the middle indexes e.g row1_col5 row1_col17 row2_col_10 and so on.</li> </ol> <p>example:</p> <pre><code>A = [ 0 0 0 2 4 1 0 0 0 1 3 2; 0 0 0 5 1 1 1 1 0 0 0 1; 0 3 4 1 0 3 1 2 0 0 1 3; 0 0 0 0 1 3 4 5 0 0 0 0]; </code></pre> <p>for the first row the middle value will be 5 and 11 and so on So if anyone could please advise how can I do this with least processing as this can be done using loops but if there is more efficient way of doing it? Please let me know if any clarification is needed.</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USTak
    1. USTak
    plurals
    1. This table or related slice is empty.
    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. This table or related slice is empty.
    1. CODo you also want to count cases where there's a non-zero value with a zero on either side?
      singulars
      1. POMidpoints of matrix rows depending on certain conditions Matlab
      1. USnkjt
    2. CO@nkjt If you mean by this that the first or last col are non-zero, then yes
      singulars
      1. POMidpoints of matrix rows depending on certain conditions Matlab
      1. USTak
 

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