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Screensize: 640 x 480 800 x 600 1024 x 768 1280 x 1024 UserName: Password: Anti-Spam Code: Format Mode: Basic  Help  Prompt  Format: Font Andale Mono Arial Arial Black Book Antiqua Century Gothic Comic Sans MS Courier New Georgia Impact Lucida Console Script MT Bold Stencil Tahoma Times New Roman Trebuchet MS Verdana   Size 1 2 3 4 5 6   Color Black Red Yellow Pink Green Orange Purple Blue Beige Brown Teal Navy Maroon LimeGreen Message: * HTML is OFF * Forum Code is ON Smilies [quote][i]Originally posted by kubra[/i] [br]Origin Ver. and Service Release (Select Help-->About Origin): 8/8.5 Operating System:Win7 Hello I have an array of many data points (it depends on measurment, but around few thousands). These data points are not regularly distributed in array, because of measurment errors. However, i need to go through measured points (one by one), find their nearest neighbours and store x and y values in vector. Number of nearest neighbours is given by constant (between 25 and 121, from SF value given by (2*SF+1)^2). I know, these numbers are huge, and i am ok with long duration of calculating. My algorithm does that. However, it is written to find at least so many nearest neighbours, as the constant is set. So, if constant is 25, for various points it finds 27, 28, 30 etc. points, and stops, when number of them exceed value of constant. If it is less, than value of constant, it erases all values in vector, rises up array, in which it is searching for NN, and does that again. Therefore calculation time (which is by itself long enough) is extending. My code: for(C=1; C<=nmbCols-1; C++){ for(R=0; R<=nmbRows-1; R++){ if(!is_missing_value(wks.Cell(R,C))){ i=SF; j=SF; do{ for(rR=R-j; rR<=R+j; rR++){ if(rR<0 || rR > nmbRows-1){ ; } if(rR>=0){ for(cC=C-i; cC<=C+i; cC++){ if(cC<=0 || cC > nmbCols-1){ ; } if(cC>0){ if(!is_missing_value(wks.Cell(rR,cC))){ vecH.Add(wks.Cell(rR, 0)); vecM.Add(wks.Cell(rR, cC)); } if(is_missing_value(wks.Cell(rR,cC))){ ; } if(cC==C+i){ break; } } } } if(rR==R+j){ break; } } if((vecM.GetSize())<((2*SF+1)^2)){ i++; j++; vecH.RemoveAll(); vecM.RemoveAll(); } if((vecM.GetSize())>=((2*SF+1)^2)){ ; } }while((vecM.GetSize())<((2*SF+1)^2)); After code is finished, program does euclidian distances calculations from the calculated data point, and sorts them in vector, and by that it chooses desired number of NN. I know, it is very specific problem. Maybe if somebody has already done NN algorithm, or there is Origin C command i haven´t found...or has an idea for such edit of code, so it would not have to do repeating calculations... I would really appreciate it :) [/quote]   Check here to include your profile signature. Check here to subscribe to this topic.