LabVIEW
Efficient way to replace array subset into an array at discontigous indices
Solved!
@siddharth9678 wrote:
Hello Team,
There is an input array of size 4 which is fed as an input to a for loop. With in loop, i have an zero initialized array of size 100, in each iteration have to assign the input array at 4 different indices....so basically loop runs 25 times and in each iteration input array of size 4 gets assigned at 4 different indexes of 100 size array.
lets say iteration 1, indexes are 1,9,11,20 and data is D0,D1,D2,D3. So D0 is replaced at index1, D1 is replaced at index 9 and so on
Simplest way to implement is 4 array replacements per iteration....Is there any efficient way to implement it in a single replacement array
operation or min replacements per iteration. 1 efficient way is to create a mask and then use it to implement the particular case.
We typically do much better looking at some LabVIEW code instead of long ambiguous descriptions.
So you have an array of four elements and these elements don't change during the execution of the loop.
Then you have an array of size 100, filled initially with zeroes.
With each iteration, four of the zeroes are replaced depending on some other input that has not been mentioned. Is that a 2D array with 25 rows, each row containing four indices?
After four elements have been replaced, should they remain for the next iterations or should the next iteration start from an array of zeroes again? If they remain, what should happen if an index occurs a second time?
Is that array temporary (to be processed in the loop) or should it form a 2D array with 25 rows and 100 columns?
What are ALL the inputs? What is the desired final result?
What is the purpose of all this? Maybe there is an entirely better way to do whatever you are trying to do.
@paul_a_cardinale wrote:
Not really what you're asking about, but I find it handy sometimes.
Enlarging an array by padding an array with default elements is typically simpler with "reshape array".
@altenbach wrote:
@paul_a_cardinale wrote:
Not really what you're asking about, but I find it handy sometimes.
Enlarging an array by padding an array with default elements is typically simpler with "reshape array".
That's a nice little trick! I had forgot about that!
"
| If the product of the dimension sizes is greater than the number of elements in the input array, the function pads the new array with the default of the data type of n-dim array." |
Personally, I would use flat code (reshaping to the same size is a noop, i.e. free). It should also handle array inputs.
Here's a "non-vim" draft.
Similarly, a vim could be made to work with arrays of higher dimension.
@altenbach wrote:
Personally, I would use flat code (reshaping to the same size is a noop, i.e. free). It should also handle array inputs.
Here's a "non-vim" draft.
Similarly, a vim could be made to work with arrays of higher dimension.
Here it is as a .vim. Adding more dimensions gets complicated: suppose you're placing 1D subarray into a 2D array; now you have to specify orientation (insert as a column, or row). I don't even want to think about higher dimensions.
