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I don't know if I should post this as a "challenge" or in the "programming help" section...anyway...here it is. What I want to do is to take 2 arrays and interleave them, so that the values from each array are (approxamately) evenly distributed in a third array. I know how to do this, but want to know if anyone has a more elegant way. My method is to create a new array sized the sum of size of the 2 original arrays. Then, this array is filled with alternating chuncks from each array. The size of the chunk is determined by dividing the larger array by the smaller then inserting the whole number followed by a single element from the smaller array.

if, for example, array1 contained 3 elements elements: x,x,x
and arrat2 contained 11 elements: a,a,a,a,a,a,a,a,a,a,a

My method produces a third array containing:

aaaxaaaaxaaaax

I would like to have the elements more evenly distributed, for example: aaxaaaxaaaxaaa

Does anyone see an efficient way to do this?

Thanks. The following snippet should get us started on the same page...

Code:
```'INPUT "Number of elements in Array 1";s1 'Input "Range for values in array 1 (0 to ?)";r1 'Input "Number of elements in Array 2";s2 'input "range for values in array 2 (0 to ?)";r2 s1=100   'array1...100 elements between 0 and 5 r1=5 s2=20    'array2...20 elements between 0 and 30 r2=30 dim array1(1 to s1) as integer dim array2(1 to s2) as integer for x=1 to s1 array1(x)=rnd*r1   'fill array1 with values next x for x=1 to s2       'fill array2 with values array2(x)=rnd*r2 next x DIM array3(1 TO (UBOUND(a)-LBOUND(a))+(UBOUND(b)-LBOUND(b))) AS INTEGER 'How to fill array3 with interleaved elements of array1 and array2???```

Thanks
since the mixing isn't critical, I decided to just use

xxaaaaaxx

to mix aaaaa with xxxx

thanks again
errr if it turns out to be critical...
say that second array is smaller than the first array.

Goes something like this (untested and prolly faulty):

Code:
```ratio% = len.first.array% / len.second.array% len.third.array% = len.first.array%+len.second.array% extra% = (len.first.array% - ratio% * len.first.array%) / 2 if extra% > 0 then extra1% = extra%/2 extra2% = extra%-extra1% for i% = 1 to extra1% third.array%(I%) = first.array%(I%) next i% for i% = len.third.array% - extra2% + 1 to len.third.array% third.array%(I%) = first.array%(I%) next i% end if for I% = extra%+1 to len.third.array% - extra% if j%< ratio% then j% = j% + 1 else j% = 0 if j%>0 then third.array%(i%) = first.array%(i%) else third.array%(i%) = second.array%(i%) next i%```
Quote:errr if it turns out to be critical...
say that second array is smaller than the first array.

Goes something like this (untested and prolly faulty):

Thanks for the response. It turns out that your code idea had some...um... problems :roll: however, it got me thinking. I was hoping there was an easier way than what I ended up using, since interleaving the arrays was just a very small part of a larger program...anyway...the following sub will do the trick with any 2 arrays.

The example shown uses text arrays to make the demo-display easy to understand. However, the array mixer works fine on any datatype, as long as it's correctly specified in the call.

Code:
```DEFINT A-Z DECLARE SUB mix (small() AS STRING, large() AS STRING, combined() AS STRING) CLS DO   DO    INPUT "size of array1"; sa1    INPUT "size of array2"; sa2   LOOP UNTIL sa1 > 0 AND sa2 > 0   combosize = sa1 + sa2   REDIM array1(1 TO sa1) AS STRING   REDIM array2(1 TO sa2) AS STRING   REDIM combo(1 TO combosize) AS STRING   FOR x = 1 TO sa1     array1(x) = "x"     PRINT array1(x);   NEXT x   PRINT   FOR x = 1 TO sa2     array2(x) = "a"     PRINT array2(x);   NEXT x   PRINT   IF UBOUND(array1) > UBOUND(array2) THEN  'put small array first in argument list     CALL mix(array2(), array1(), combo())   ELSE     CALL mix(array1(), array2(), combo())   END IF   FOR x = 1 TO UBOUND(combo)     PRINT combo(x);   NEXT x   PRINT LOOP END SUB mix (small() AS STRING, large() AS STRING, combined() AS STRING) SAS = UBOUND(small)     'Small Array Size LAS = UBOUND(large)      'Large Array Size CAS = UBOUND(combined)  'Combined Array Size TC = SAS + 1               'Total Chunks SCS = LAS \ (SAS + 1)      'Small Chunk Size LCS = SCS + 1              'Large Chunk Size SAP = 1: LAP = 1: CAP = 1  'Small, Large, Combined Array Position NLC = LAS - (SCS * TC)     'Number of large chunks FOR x = 1 TO NLC                  'interleave starting with large chunks     FOR y = 1 TO LCS       combined(CAP) = large(LAP)       CAP = CAP + 1: LAP = LAP + 1        NEXT y     combined(CAP) = small(SAP)     CAP = CAP + 1: SAP = SAP + 1 NEXT x FOR x = 1 TO TC - NLC              'interleave small chunks     FOR y = 1 TO SCS       combined(CAP) = large(LAP)       CAP = CAP + 1: LAP = LAP + 1        NEXT y     IF x = TC - NLC THEN EXIT SUB  'out of data...exit sub     combined(CAP) = small(SAP)     CAP = CAP + 1: SAP = SAP + 1 NEXT x END SUB```