represents the units (in sense of dimensional analysis) of a variable. More...

#include <units.h>

Inheritance diagram for minsky::Units:

Collaboration diagram for minsky::Units:

Public Member Functions
	Units ()

	Units (const std::string &)

std::string	str () const

std::string	latexStr () const
	insert braces around exponents for LaTeX processing More...

void	normalise ()

Detailed Description

represents the units (in sense of dimensional analysis) of a variable.

first argument is the base unit (eg metre, second), and the second is it's power (eg {{"m",1},{"s",-1}} => m/s)

Definition at line 34 of file units.h.

Constructor & Destructor Documentation

◆ Units() [1/2]

minsky::Units::Units ( )

inline

Definition at line 36 of file units.h.

36 {}

◆ Units() [2/2]

minsky::Units::Units ( const std::string & x )

Definition at line 56 of file variableType.cc.

   {
     if (x.empty()) return;
     // split into numerator and denominator components if / found
     auto divPos=x.find('/');
     vector<string> components;
     components.push_back(x.substr(0,divPos));
     if (divPos!=string::npos)
       components.push_back(x.substr(divPos+1));
     
     if (components.back().find('/')!=string::npos)
       throw runtime_error("too many division signs: "+x);
     
     int coef=1;
     for (auto& i: components)
       {
         if (i.empty())
           throw runtime_error("empty numerator or denominator: "+x);
         const char* b=i.c_str();
         for (const char*j=b;;)
           {
             if (*j=='^'||*j=='\0'||isspace(*j))
               {
                 const string name(b,j); // stash end of unit name
                 if (name.empty())
                   throw runtime_error("empty unit name: "+x);
                 while (isspace(*j)) ++j;
                 if (*j=='^')
                   {
                     auto k=j+1;
                     const int v=strtol(k,const_cast<char**>(&j),10);
                     if (j==k)
                       throw runtime_error("invalid exponent: "+x);
                     if (name!="1")
                       (*this)[name]+=coef*v;
                   }
                 else if (name!="1")
                   (*this)[name]+=coef;
                 if ((*this)[name]==0)
                   erase(name);
                 while (isspace(*j)) ++j;
                 b=j; // update to next unit name
                 if (*j=='\0') break; //loop exits here
               }
             else
               ++j;
           }
         if (b==i.c_str()) // we haven't found any exponents
           emplace(i,coef);
         coef*=-1;
       }
   }

Member Function Documentation

◆ latexStr()

string minsky::Units::latexStr ( ) const

insert braces around exponents for LaTeX processing

Definition at line 40 of file variableType.cc.

References minsky::to_string().

   {
     string s;
     for (auto& i: *this)
       if (!i.first.empty() && i.second!=0)
         {
           s+=i.first;
           if (i.second!=1)
             s+="^{"+to_string(i.second)+"}";
           else
             s+=" ";
         }
     return s;
   }

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◆ normalise()

void minsky::Units::normalise ( )

inline

Definition at line 42 of file units.h.

Referenced by minsky::UnitsExpressionWalker::operator*=(), minsky::UnitsExpressionWalker::operator/=(), minsky::Derivative::units(), and minsky::OperationBase::unitsBinOpCase().

                      {
       for (auto i=begin(); i!=end(); ) {
         auto j=i; ++i;
         if (j->second==0 || j->first.empty()) erase(j);
       }
     }

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◆ str()

string minsky::Units::str ( ) const

Definition at line 33 of file variableType.cc.

Referenced by minsky::GodleyIcon::stockVarUnits(), minsky::SwitchIcon::units(), minsky::VariableBase::units(), and minsky::VariableBase::unitsStr().

   {
     ostringstream s;
     s<<*this;
     return s.str();
   }