### SparseCompress - compress sparse array

Miscellaneous functions
(AFL 4.0)

 SYNTAX SparseCompress( query_points, data ) RETURNS ARRAY FUNCTION The function gets values from 'data' array at points defined by non-zero values of 'query_points' array and compresses them so they are squeezed at the end of resulting array EXAMPLE ```only_when = ( Month() % 2 ) == 0; // even months only x = SparseCompress( only_when, Close ); // compact sparse data y = MA( x, 10 ); // regular calculation y = SparseExpand( only_when, y ); // expand sparse data Plot( C, "Price", colorDefault, styleBar ); Plot( y, "Sparse MA from even months", colorRed ); function SparseCompressEquiv( sparse_array, data_array ) {      result = Null;           j = BarCount - 1;      for( i = BarCount - 1; i >= 0; i-- )      {        if( sparse_array[ i ] ) result[ j-- ] = data_array[ i ];      }           return result; } function SparseExpandEquiv( sparse_array, data_array ) {      result = Null;           j = BarCount - 1;      for( i = BarCount - 1; i >= 0; i-- )      {        if( sparse_array[ i ] ) result[ i ] = data_array[ j-- ];      }           return result; }``` SEE ALSO SparseExpand() function

#### References:

The SparseCompress function is used in the following formulas in AFL on-line library: