>>Hello - Unfortunately vfp software doesn't let me create a square sparse matrix (as is doing - for example Matlab software); because I need to overcome the limit of 65,000 memory variables (even double ...) , I'm looking for a solution - anyone has a idea - it is welcome. Thanks in advance for your help, bye, Sorin
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>(1) Use Collections - the key would be the string of the index
>For mulitdimension you'll need to add other collecttions
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>This becomes a bit messy
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>(2) If all elements are the same type, use SafeArray
>SafeArrays are allocated by windows
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>http://msdn.microsoft.com/en-us/library/ms221145(v=VS.85).aspx
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>- SaveArrayCreate() or SafeArrayCreateEx() for structures
>You can specify the number of dimensions and the lower/upperbounds for each dimension
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>- SafeArrayCreateVector() for one dimensional arrays
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>- SafeArrayDestroy() when you no longer need it
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>- SafeArrayPutElement () to assign a value to an element
>- SafeArrayGetElement() to get the contents fo an element
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>(3) a Cursor may be the simplest way

I like the cursor idea:

PrimaryKey   XSubscript   YSubscript   (ZSubscript...)   Value

   1             1             1            ...            42
  ...

Completely sparse "array" with up to about 250 "dimensions", if you want. Easy to insert/remove elements as needed.