c++ - Correctly formatting the output -

my software has show end result user, data received though uart port, need format , round data.

i did write algorihtm that, feeling there has better solution.

my output can have mutiple ranges, need round , format correctly.

example:

1 of many results go ->

0.000 ohm 2.000 ohm

2.01 ohm 20.00 ohm

20.1 ohm 100.0 ohm

100 ohm 200 ohm

i made simple structure hold basic data formating

struct _range {   float from; //0.000 first example    float to; //2.000    int decimal; //3, decimal places need   int unit; //unit format, ohm in example   float div; //sometimes need divide result @ range   //example, when reach 1000va need divide 1000 1kva }; 

i have static function called addunittoresult, 1 add unit result.

now asking me write function correctly format result string , round double ( need double later compare ).

correctly format means if result 0, should format 3 dedimal places.

i hope can me guys

edit:

this have handle round , dividing.

void resultbox::setresult(float res) {     this->measurecounter++;     this->valueavg +=res;     if (res > this->valuemax)         this->valuemax = res;     if (res < this->valuemin)         this->valuemin = res;       float tttmp;     if (this->rangecount > 0 && this->ranges[0].decimal >= 0)     {         tttmp = converter::cutdecimal(res,this->ranges[0].decimal);     }         int decimal = getdecimalplaces(res,0);      float div = getdivision(res);      int unit = getunit(res);     tttmp=tttmp/div;     this->result = tttmp;      float tmpres = res /div;      this->isvalid =true;      wchar restext[20];     wchar finaltext[20];     wchar maxtext[20];     wchar mintext[20];      char restext[20];      tmpres = res/div;;      std::ostringstream ss;     ss << std::fixed << std::setprecision(decimal) << tttmp;     std::string s = ss.str();     if (decimal > 0 && s[s.find_last_not_of('0')] == '.')     {          s.erase(s.size()-decimal+1);     }        converter::dtoa(restext,tmpres);     switch(decimal)     {     case 0:         if (floor(tttmp) == tttmp)         {             swprintf(restext,l"%.0f",tttmp);         }else         {             swprintf(restext,l"%s",s.c_str());         }          swprintf(maxtext,l"%.0f",this->getmax());         swprintf(mintext,l"%.0f",this->getmin());         break;     case 1:         if (floor(tttmp) == tttmp)         {             swprintf(restext,l"%.1f",tttmp);         }else         {             swprintf(restext,l"%s",s.c_str());         }          swprintf(maxtext,l"%.1f",this->getmax());         swprintf(mintext,l"%.1f",this->getmin());         break;     case 2:         if (floor(tttmp) == tttmp)         {             swprintf(restext,l"%.2f",tttmp);         }else         {             swprintf(restext,l"%s",s.c_str());         }          swprintf(maxtext,l"%.2f",this->getmax());         swprintf(mintext,l"%.2f",this->getmin());         break;     case 3:         if (floor(tttmp) == tttmp)         {             swprintf(restext,l"%.3f",tttmp);         }else         {             swprintf(restext,l"%s",s.c_str());         }          swprintf(maxtext,l"%.3f",this->getmax());         swprintf(mintext,l"%.3f",this->getmin());         break;     case 4:         if (floor(tttmp) == tttmp)         {             swprintf(restext,l"%.4f",tttmp);         }else         {             swprintf(restext,l"%s",s.c_str());         }          swprintf(maxtext,l"%.4f",this->getmax());         swprintf(mintext,l"%.4f",this->getmin());         break;     case 5:         if (floor(tttmp) == tttmp)         {             swprintf(restext,l"%.5f",tttmp);         }else         {             swprintf(restext,l"%s",s.c_str());         }          swprintf(maxtext,l"%.5f",this->getmax());         swprintf(mintext,l"%.5f",this->getmin());         break;     }       //pogledamo če je majni     if (res < this->getmin())     {         if (lowerenabled == true)         {             wcscpy(finaltext,l"<");         }         else         {             wcscpy(finaltext,l"");         }         wcscat(finaltext,mintext);     }     else if (res > this->getmax())     {         wcscpy(finaltext,l">");         wcscat(finaltext,maxtext);     }     else     {         wcscpy(finaltext,restext);     }     if (res == this->getmin())     {         wcscpy(finaltext,mintext);     }     if (res == this->getmax())     {         wcscpy(finaltext,maxtext);     }      if (this->unitbox)     {         wchar mm[10];         wcscpy(mm,l"");         tabsguiproxy::margeresultandunit(mm,unit);         if (mm[0] == ' ')             this->unitbox->settext(&mm[1]);         else             this->unitbox->settext(mm);     }      this->m_ptextblock->settext(finaltext);     if (this->resultlimit)     {         if (unit == measruement_units::kva)         {             float fff = this->resultlimit->getvalue()*1000;             std::wostringstream ss1;             ss1 << std::fixed << std::setprecision(decimal) << fff;             std::wstring s1 = ss1.str();             if (decimal > 0 && s1[s1.find_last_not_of('0')] == '.')             {                 s1.erase(s1.size()-decimal+1);             }              if (wcscmp(restext,s1.c_str()) == 0)             {                  this->setgoodresult();             }else             {                 float mmm = fabs(_wtof(s1.c_str()) - this->resultlimit->getvalue()*1000) ;                 //else if (fabs(idelresoult - ideltalim) <= 0.001 || idelresoult < ideltalim)                 if (mmm<= 0.001 || tttmp < (_wtof(s1.c_str())))                 {                     this->setgoodresult();                 }                 else                 {                     this->setbadresult();                 }             }         }         else         {             float fff = this->resultlimit->getvalue();             std::wostringstream ss1;             ss1 << std::fixed << std::setprecision(decimal) << fff;             std::wstring s1 = ss1.str();             if (decimal > 0 && s1[s1.find_last_not_of('0')] == '.')             {                 s1.erase(s1.size()-decimal+1);             }              if (wcscmp(restext,s1.c_str()) == 0)             {                  this->setgoodresult();             }             else             {                 float mmm = fabs(_wtof(restext) - this->resultlimit->getvalue()) ;                 //else if (fabs(idelresoult - ideltalim) <= 0.001 || idelresoult < ideltalim)                 if (mmm<= 0.001 || tttmp < (_wtof(s1.c_str())))                 {                     this->setgoodresult();                 }                 else                 {                     this->setbadresult();                 }             }         }     }  } 

let me try explain bit more:

i use struct _range set valid ranges output, when init result create mutiple struct of type range.

let have:

range1 -> 0.000 2.000 ohm range2 -> 2.01 20.00 ohm range3 -> 20.1 100.0 ohm range4 -> 101 200 ohm

when init result create array of 4 struct each containing data

range1 ->  struct _range {   float    = 0.000    float      = 2.000   int   decimal =3;   int   unit        = ohm; //unit format, ohm in example   float div     =1;  };  range2 ->  struct _range {   float    = 2.01    float      = 20.00   int   decimal =2;   int   unit        = ohm; //unit format, ohm in example   float div     =1;  };  range3 ->  struct _range {   float    = 20.1    float      = 100.0   int   decimal =1;   int   unit        = ohm; //unit format, ohm in example   float div     =1;  };  range4 ->  struct _range {   float    = 101    float      = 200   int   decimal =0;   int   unit        = ohm; //unit format, ohm in example   float div     =1;  }; 

now input function can 0 200, , have format text , round float acording ranges in structures.

i hope explains bit more

i think start improve code adding "format" member _range struct this:

struct _range {   float from; //0.000 first example    float to; //2.000    int decimal; //3, decimal places need   int unit; //unit format, ohm in example   float div; //sometimes need divide result @ range   //example, when reach 1000va need divide 1000 1kva   char * format; }; 

then initialize instances of range struct this:

range1.from    = 0.000; range1.to      = 2.000; range1.decimal = 3; range1.format  = "%.3f";  range2.from    = 2.01; range2.to      = 20.00; range2.decimal = 2; range2.format  = "%.2f"; 

then reference format string appropriate range instance when print value. maybe this:

sprintf(pstr, prangeofvalue->format, value);