Selected small useful codes
Some interesting codes developed by me as part of my projects. Please ask for details of codes as you may need class definitions.(The below codes are to understand the solution for respective problems. Readers are advised to ignore class or function names and concern to formula or logic in use. Scroll down for other technologies code)
in VC++: typedef struct{double x;
double y;
int strokeNumber;
}CPointNormalized;CArray<CPointNormalized, const CPointNormalized&> m_PPArray;To find curliness of a trajectory
double CFeature::Curliness(int From, int To, CPointNormalized& LeftP,CPointNormalized& RightP, CPointNormalized& BottomP, CPointNormalized& TopP)
{CPreprocessing ObjPP;
CPointNormalized P1, P2;
double SL=0, Lx, Ly; ///S is sum of line segments in a stroke
int i;
for(i=From;i<To;i++)
{
P1=m_PPArray.GetAt(i);
P2=m_PPArray.GetAt(i+1);
SL+=ObjPP.Distance(P1, P2);
}
Lx=fabs(ObjPP.Distance(RightP, LeftP));
Ly=fabs(ObjPP.Distance(BottomP, TopP));
if(Ly>Lx) Lx=Ly;
return((SL/Lx)-2);
}To find Linearity of a trajectory
double CFeature::Linearity(int From, int To, CPointNormalized& StartP,CPointNormalized& EndP)
{double L=0,m,c,x,y;
int i, N=(To-From)+1;
m=(EndP.y-StartP.y)/(EndP.x-StartP.x);
c=StartP.y-m*StartP.x;
for(i=From; i<=To; i++)
{
x=m_PPArray.GetAt(i).x; y=m_PPArray.GetAt(i).y;
L+=pow(PerpendicularDistance(m,c,x,y), 2);
}
return(L/N);
}To check loop exists in trajectory, trajectory stored in an array or list
int CFeature::LoopExists(CPointNormalized& P, CPointNormalized& P1, CPointNormalized& P2,CPointNormalized& P3, CPointNormalized& P4)
{int t=0;
if(P1.x<=P2.x)
{
if(P1.y<=P2.y)
{
if(P.x>=P1.x && P.x<=P2.x && P.y>=P1.y && P.y<=P2.y)
t++;
}
else
{
if(P.x>=P1.x && P.x<=P2.x && P.y<=P1.y && P.y>=P2.y)
t++;
}
}
else
{
if(P1.y<=P2.y)
{
if(P.x<=P1.x && P.x>=P2.x && P.y>=P1.y && P.y<=P2.y)
t++;
}
else
{
if(P.x<=P1.x && P.x>=P2.x && P.y<=P1.y && P.y>=P2.y)
t++;
}
}
////////////////////////for next line P3, P4if(P3.x<=P4.x)
{
if(P3.y<=P4.y)
{
if(P.x>=P3.x && P.x<=P4.x && P.y>=P3.y && P.y<=P4.y)
t++;
}
else
{
if(P.x>=P3.x && P.x<=P4.x && P.y<=P3.y && P.y>=P4.y)
t++;
}
}
else
{
if(P3.y<=P4.y)
{
if(P.x<=P3.x && P.x>=P4.x && P.y>=P3.y && P.y<=P4.y)
t++;
}
else
{
if(P.x<=P3.x && P.x>=P4.x && P.y<=P3.y && P.y>=P4.y)
t++;
}
}
return t;
}int CFeature::LoopCheck(int i, int j, int choice){double m1, m2, c1, c2; ///Slopes and Intercepts of lines
CPreprocessing ObjPP;
CPointNormalized P, P1, P2, P3, P4;
P1=m_PPArray.GetAt(i); P2=m_PPArray.GetAt(i+IC);
P3=m_PPArray.GetAt(j); P4=m_PPArray.GetAt(j+IC);
m1 = ObjPP.CalculateSlope(P1, P2); c1 = P1.y-m1*P1.x;
m2 = ObjPP.CalculateSlope(P3, P4); c2 = P3.y-m2*P3.x;
if(m1==m2) return 0;
if(m1==-9999)
{
P.x=P1.x; P.y=m2*P.x+c2;
}
else if(m2==-9999)
{
P.x=P2.x; P.y=m1*P.x+c1;
}
else
{
P.x=(c2-c1)/(m1-m2); P.y=(m1*c2-m2*c1)/(m1-m2);
}
P.strokeNumber=P1.strokeNumber;
if(LoopExists(P, P1, P2, P3, P4)>=2 && choice==1)
return 1;
if(LoopExists(P, P1, P2, P3, P4)>=2 && choice==2)
return 1;
return 0;
}int CFeature::Loop(int From, int To){int i, j, loop=1, lc=0, rlc=0; IC=1; //loop is for loop identity
for(i=From; i<To-3; i=i+IC)
{
j=i+2;
while(j<To)
{
lc=LoopCheck(i,j,loop);
if(lc==1 && (j-i)>1) //for strict visible loop and avoid overwriting
rlc = rlc*10+lc;
j=j+IC;
}
}
return rlc;
}To check given trajectory behave as horizontal line or not
int CFeature::HeadLine(int From, int loop){bool Range=false;
double Linearity, Curliness, Slope, TestP; //linearity nad curliness
int i, SN; SN=m_PPArray.GetAt(From).strokeNumber;
TestP=(BP()+TP())/2;
for(i=0; i<=m_LowLevelFArray.GetUpperBound(); i++)
{
if(SN==m_LowLevelFArray.GetAt(i).SN)
{
Linearity=m_LowLevelFArray.GetAt(i).Linearity;
Curliness=m_LowLevelFArray.GetAt(i).Curliness;
Slope=m_LowLevelFArray.GetAt(i).Slope;
if(m_LowLevelFArray.GetAt(i).BottomP.y>=TestP)
Range=true;
break;
}
}
///check for curliness
if(Slope>=-1 && Slope<=1 && Range==true && Linearity<=2 && loop==0)
return 1;
else
return 0;
}To check given trajectory behave as vertical straight line or not
int CFeature::StraightLine(int From, int loop, int hl){CLowLevelF L; CPreprocessing ObjPP;
double Linearity, Curliness, Slope, Length; //linearity nad curliness
int i, SN; SN=m_PPArray.GetAt(From).strokeNumber;
for(i=0; i<=m_LowLevelFArray.GetUpperBound(); i++)
{
if(SN==m_LowLevelFArray.GetAt(i).SN)
{
L=m_LowLevelFArray.GetAt(i);
Linearity=L.Linearity;
Curliness=L.Curliness;
Slope=L.Slope;
Length=fabs(ObjPP.Distance(L.StartP, L.EndP));
break;
}
}
if((Slope>=2.74 || Slope<=-2.74) && Length>=30 && Linearity<=2 && loop==0 && hl==0)
return 1;
else
return 0;
}To check given trajectory behave as a dot or 'bindu'
int CFeature::Dot(int From, int loop, int crossing, int hl, int sl){CLowLevelF L; CPreprocessing ObjPP;
double Length, Height;
int i, SN; SN=m_PointArray.GetAt(From).strokeNumber;
for(i=0; i<=m_LowLevelFArray.GetUpperBound(); i++)
{
if(SN==m_LowLevelFArray.GetAt(i).SN)
{
L=m_LowLevelFArray.GetAt(i);
Length=fabs(ObjPP.Distance(L.StartP, L.EndP));
Height=fabs(ObjPP.Distance(L.BottomP, L.TopP));
break;
}
}
if(Length<=10 && Height<=10 && loop==0 && crossing==0 && hl==0 && sl==0)
return 1;
else
return 0;
}To find third point for two consecutive points of trajectory (as equilateral triangle)
CPointNormalized CRecognitionDialog::FindThirdPoint(CPointNormalized pStart, CPointNormalized pMid, CPointNormalized pEnd){double m, k, L, a, b, c;
CPointNormalized P1,P2;
if((pEnd.x-pStart.x)==0) m=9999;
else m=(pEnd.y-pStart.y)/(pEnd.x-pStart.x);
k=((pStart.x*pStart.x+pStart.y*pStart.y)-(pEnd.x*pEnd.x+pEnd.y*pEnd.y))/(2*(pEnd.x-pStart.x));
L=(pEnd.x-pStart.x)*(pEnd.x-pStart.x)+(pEnd.y-pStart.y)*(pEnd.y-pStart.y);
if(m==0)
{
P1.x=-k; P2.x=-k;
a=1; b=2*pEnd.y; c=pEnd.y*pEnd.y+k*k+pEnd.x*pEnd.x+2*pEnd.x*k-L;
P1.y=((-b)+sqrt(b*b-4*a*c))/(2*a); P2.y=((-b)-sqrt(b*b-4*a*c))/(2*a);
}
else
{
a=1+m*m; b=2*(m*pStart.y+k-pStart.x*m*m);
c=m*m*(pStart.x*pStart.x+pStart.y*pStart.y-L)+2*m*pStart.y*k+k*k;
P1.x=((-b)+sqrt(b*b-4*a*c))/(2*a); P2.x=((-b)-sqrt(b*b-4*a*c))/(2*a);
P1.y=-(P1.x+k)/m; P2.y=-(P2.x+k)/m;
}
if(Distance(P1,pMid)>=Distance(P2,pMid))
return P1;
else
return P2;
}To find angle in degrees for two consecutive points of trajectory
double CRecognitionDialog::Angle(CPointNormalized P1, CPointNormalized P2){double radian, degree, k=(180/3.14);
if(P1.x==P2.x)
{
if(P1.y<=P2.y)
return 90;
else
return 270;
}
else
{
radian=atan((P2.y-P1.y)/(P2.x-P1.x));
degree=radian * k; degree = fabs(degree);
if(P2.x>P1.x && P1.y<=P2.y) return degree;
else if(P2.x>P1.x && P1.y>=P2.y) return (270+(90-degree));
else if(P2.x<P1.x && P1.y<=P2.y) return (90+(90-degree));
else if(P2.x<P1.x && P1.y>=P2.y) return (180+degree);
}
return degree;
}To find files in a path
void CHWRAnujView::FindFiles(CString FilePath){CFileFind WriterFile; CString FilePath2;
FilePath+=_T("\\*.*");
BOOL find = WriterFile.FindFile(FilePath);
while(find)
{
find = WriterFile.FindNextFileA();
if(WriterFile.IsDots()) continue;
else if(WriterFile.IsDirectory())
{
FilePath2 = WriterFile.GetFilePath();
FindFiles(FilePath2);
}
else
{
m_files++;
ReadFiles(WriterFile.GetFilePath()); //to further read a file
}
}
WriterFile.Close();
}To make list numbers decimal points free (example 2.75 becomes 2)
void CPreprocessing::NonDecimalPoints(){int i, Size;
double fraction, t;
CPointNormalized P; //Defined at top
Size=m_PPArray.GetSize(); //m_PPArray list or array name
for(i=0; i<Size; i++)
{
P=m_PPArray.GetAt(i);
fraction=modf(P.x, &t);
if(fraction>0.5) P.x=P.x+1-fraction;
else P.x=P.x-fraction;
fraction=modf(P.y, &t);
if(fraction<-0.5) P.y=P.y-1-fraction;
else P.y=P.y-fraction;
m_PPArray.SetAt(i, P);
}
}To find maximum and minimum values and their y-x ratio in Array or list
void CPreprocessing::CalculateMaxMinText(){int i, Size;
CPointNormalized TempPoint; //Defined at top
Size=m_PPArray.GetSize(); //m_PPArray list or array name
xMax=0; xMin=ConstantHighPlusValue; yMax=ConstantHighLowValue; yMin=0;
for(i=0; i<Size; i++)
{
TempPoint = m_PPArray.GetAt(i);
if(TempPoint.x > xMax)
xMax = TempPoint.x;
if(TempPoint.x < xMin)
xMin = TempPoint.x;
if(TempPoint.y > yMax)
yMax = TempPoint.y;
if(TempPoint.y < yMin)
yMin = TempPoint.y;
}
m_yxRatio=(double)fabs(yMin)/xMax;
}To calculate perpendicular distance for y=mx+c from (x1,y1)
double CFeature::PerpendicularDistance(double m, double c, double x1, double y1){return(fabs((m*x1-y1+c)/(sqrt(m*m+1))));
}To filter repeat points in array or list
void CFeature::FilterRepeatPoints(){CPointNormalized Pi, Pj; //Defined at top
int i,j, Size; Size=m_PPArray.GetSize(); //m_PPArray list or array name
if(Size>0)
{
for(i=0;i<m_PPArray.GetUpperBound();i++)
{
for(j=i+1;j<=m_PPArray.GetUpperBound();j++)
{
Pi=m_PPArray.GetAt(i); Pj=m_PPArray.GetAt(j);
if(Pi.x==Pj.x && Pi.y==Pj.y)
m_PPArray.RemoveAt(j);
}
}
}
}in Java/ J2ME fo symbian operating systemTo write in a file in mobile based platform
public void WriteFile() throws IOException{ String path; byte[] bytePL = currentList.getBytes(); javax.microedition.io.Connection con = null; java.io.OutputStream os = null; if(forMb) path = "file:///e:/fileName.txt"; //if using mobile else path = "file:///root1/att/fileName.txt"; //if using emulators try { con = javax.microedition.io.Connector.open(path, javax.microedition.io.Connector.READ_WRITE); javax.microedition.io.file.FileConnection fcon = (javax.microedition.io.file.FileConnection) con; if (!fcon.exists()) fcon.create(); os = fcon.openOutputStream(fcon.fileSize()); os.write(bytePL); os.flush(); } catch (Exception e) { System.out.println("file not created by author"); } finally { try { if (os != null) os.close(); if (con != null) con.close(); } catch (Exception ex) { ex.printStackTrace(); } } }To read from a file in mobile based platform
public void getLines(){ InputStream inputStreamText =null; inputStreamText = this.getClass().getResourceAsStream("fileName.txt"); StringBuffer buf = new StringBuffer(); int i ; while ((i = inputStreamText.read()) != -1) { char ch = (char)i; if (ch == '\n') { lines.addElement(buf.toString()); buf.delete(0,buf.length()); } else buf.append(ch); } inputStreamText.close(); }To get array from string, where data is trajectory of X-Y position and x and y positions start with 'X' and 'Y', trajectory end with ';' and new pen up in trajectory start with 'S'.
void GetArrayFromString(String Line, int choice) { int i=0, l, indx=0; double AngleLine; String ps; Point P1, P2; TemplatePoint ObjT; P1=new Point(); P2=new Point(); ObjT = new TemplatePoint();
i=2; l=Line.length(); while(i<l) { if(Line.charAt(i)==' ' || Line.charAt(i)=='-' || Line.charAt(i)=='S') break; if(Line.charAt(i)==';') break; if(Line.charAt(i)=='X') { i++; ps=""; while(Line.charAt(i)!='Y') { ps+=Line.charAt(i); i++; } P2.x = Double.parseDouble(ps); } if(Line.charAt(i)=='Y') { i++; ps=""; while(Line.charAt(i)!='X') { if(Line.charAt(i)=='S') { i++; break;} if(Line.charAt(i)==';') break; ps+=Line.charAt(i); i++; } P2.y = Double.parseDouble(ps); ObjT.P=P2; if(indx==0) { P1=P2; ObjT.angle=0; } else ObjT.angle=Angle(P1, P2); if(choice==1) m_TestArray.add(ObjT); else m_TrainArray.add(ObjT); P1=P2; } // i++;
} }in VBA (macros to work with ms-excel)To merge files
Sub MergeFileFunction()Dim s1 As WorksheetDim s2 As WorksheetDim s1_currRow, s2_currRow As IntegerSet s1 = ActiveWorkbook.Sheets("sheet1")Set s2 = ActiveWorkbook.Sheets("sheet2")For s2_currRow = 1 To sheet1_row_length For s1_currRow = 1 To sheet2_row_length If s2.Cells(s2_currRow, 1) = s1.Cells(s1_currRow, 5) Then If IsEmpty(s1_currRow, 1) Then s1.Cells(s1_currRow, 1) = s2.Cells(s2_currRow, 2) s1.Cells(s1_currRow, 2) = s2.Cells(s2_currRow, 3) s1.Cells(s1_currRow, 3) = s2.Cells(s2_currRow, 4) s1.Cells(s1_currRow, 4) = s2.Cells(s2_currRow, 5) End If End If Next s1_currRowNext s2_currRowEnd Sub- To delete empty rows
Sub DeleteRowFunction()Dim currRow As LongFor currRow = 1 To num_rows If IsEmpty(Cells(currRow, 1)) Then Rows(currRow).EntireRow.Delete End IfNext currRowEnd Sub- To put data in empty cells
Sub InsertDataInCellFunction()Dim currRow As LongDim txt As Stringtxt = "txt_to_insert"For currRow = 1 Tonum_rowsIf IsEmpty(Cells(currRow, n_col)) ThenCells(currRow, n_col) = txtEnd IfNext currRowEnd Sub