/Users/kmartin/Documents/files/code/cpp/OScpp/COIN-OS/OS/src/OSUtils/OSMathUtil.cpp

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#include "OSDataStructures.h" 
#include "OSMathUtil.h"


#include <iostream>



MathUtil::MathUtil(){
}

MathUtil::~MathUtil(){
}


 
SparseMatrix* MathUtil::convertLinearConstraintCoefficientMatrixToTheOtherMajor(
        bool isColumnMajor, int startSize, int valueSize, int* start, int* index, 
        double* value, int dimension){
        if(!start || startSize <= 1 ) return NULL;
        if(!value  || !index  ) return NULL;    

        int iStartSize = dimension + 1;
        SparseMatrix *matrix ;
        matrix = new SparseMatrix( !isColumnMajor, iStartSize, valueSize);              
        int i,j, iTemp;
        int iNumSource = startSize - 1;
        int* miStart = matrix->starts;
        int* miIndex = matrix->indexes;
        double* mdValue = matrix->values;
        
        for ( i = 0; i < iStartSize; i++){                      
                miStart [ i ] = 0;
        }
        // for illustration assume we are converting from column to row major   
        // i is indexing columns (variables) and j is indexing row numbers 
        for (i = 0; i < iNumSource; i++){       
                for (j = start[i]; j < start[ i + 1 ]; j++){
                        // index[ j] is a row index, we have just found an occurance of row index[j]
                        // therefore we increase by 1 (or push back) the start of the row indexed by index[j] + 1, 
                        // i.e. the start of the next row
                        miStart[ index[j] + 1] ++;                              
                }
        }
        // at this point, miStart[ i] holds the number of columns with a nonzero in row i - 1
        // we are not done with the start indicies, if we are here, and we
        // knew the correct starting point of row i -1, the correct starting point
        // for row i is miStart[i] + miStart [i - 1]
        miStart[0] = 0;
        for (i = 1; i < iStartSize; i++ ){
                miStart[i] += miStart [i - 1] ;         
        }
        
        // now get the correct values
        // again assume we are converting column major to row major
        // loop over bariables          
        for (i = 0; i < iNumSource; i++){
                // get row indices and values of the A matrix
                for (j = start[i]; j < start[ i + 1 ]; j++){
                        iTemp = miStart[ index[j]];
                        miIndex [ iTemp] = i;
                        mdValue [ iTemp] = value[j];
                        miStart[ index[j]] ++;                          
                }                       
        } 
                
        // miStart[ i] is now equal to miStart[ i + 1], so readjust
        for (i = iStartSize - 1; i >= 1; i-- ){
                miStart[i] = miStart [i - 1] ;          
        }
                
        miStart[0] = 0;
        return matrix;          
}//convertLinearConstraintCoefficientMatrixToTheOtherMajor


double os_strtod_wrap(const char *str,  char **strEnd){
#ifndef USE_DTOA
        return strtod(str,  strEnd);    
#else
        return os_strtod(str,  strEnd);;
#endif
}//end os_strtod_wrap


std::string os_dtoa_format(double  x){
        ostringstream outStr;
#ifndef USE_DTOA
        outStr << x;
        return outStr.str();
#else
        outStr << "";
        char *charResult;
    int decimalPointPos;
    int sign;  
    int strLength = 0;
    int k = 0;
    charResult = os_dtoa(x, 0, 0, &decimalPointPos, &sign, NULL);
    // get the length
    // get the sign, 1 for negative
    if( sign == 1) outStr << "-";
    strLength = strlen( charResult);
    // return charResult if we have nan or infinity  -- if so, return orginal string
    if(decimalPointPos == 9999){
        for(k = 0; k < strLength; k++)outStr << charResult[ k];
        return outStr.str();            
    }
    if(decimalPointPos == strLength){ //don't we have an integer?
        for(k = 0; k < strLength; k++)outStr << charResult[ k];
        return outStr.str();
    } 
    if(decimalPointPos >= 0){
        if(decimalPointPos > strLength){
                // put in all of the characters from charResult
                outStr << charResult[ 0];
                outStr <<  ".";
                for(k = 1; k < strLength; k++) outStr << charResult[ k];
                //for(k = strLength; k < decimalPointPos; k++) outStr <<  "0";
                outStr <<  "e";
                outStr <<  decimalPointPos -  1;
        }else{
                for(k = 0; k < decimalPointPos; k++) outStr << charResult[ k];
                outStr <<  ".";
                for(k = decimalPointPos; k < strLength; k++) outStr << charResult[ k];
        }
    }else{
                outStr << charResult[ 0];
                outStr <<  ".";
        //for(k = 0; k < -decimalPointPos; k++) outStr << "0";
        for(k = 1; k < strLength; k++)outStr <<  charResult[ k];
                outStr <<  "e";
                outStr <<  decimalPointPos -1 ;
    }
    //
    os_freedtoa( charResult);
        return outStr.str();
#endif
}// end os_dtoa_format

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