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XSLPvalidformula

Purpose

Check a formula in internal (parsed or unparsed) format for unknown tokens

Synopsis

int XPRS_CC XSLPvalidformula(int *inType, double *inValue, int *nToken,
               char *Name, char *StringTable);

Arguments

inType	Array of token types providing the formula.
inValue	Array of values corresponding to the types in inType
nToken	Number of the first invalid token in the formula. A value of zero means that the formula is valid. May be NULL if not required.
Name	Character buffer to hold the name of the first invalid token. May be NULL if not required.
StringTable	Character buffer holding the names of the unidentified tokens (this can be created by XSLPpreparseformula).

Example

The following example pre-parses the formula "sin ( x + y )" and then tries to identify the unknown tokens:

int n, Index, NewType, Type[20];
double Value[20];
char Strings[200], Name[20];
XSLPpreparseformula(Prob, "sin ( x + y )", NULL,
                    Type, Value, Strings, NULL);
for (;;) {
  XSLPvalidformula(&Type[n], &Value[n], &n, Name, Strings);
  if (n == 0) break;
  Index = 0;
  if (Type[n+1] == XSLP_LB) { /* function */
    NewType = XSLP_IFUN;
    XSLPgetindex(Prob, XSLP_INTERNALFUNCNAMESNOCASE,
                 Name, &Index);
  }
  else { /* try for column */
    NewType = XSLP_VAR;
    XSLPgetindex(Prob, 2, Name, &Index);
  }
  if (Index) {
    Type[n] = NewType; Value[n] = Index;
  }
  else {
    printf("\nUnidentified token %s",Name);
    break;
  }
}

XSLPpreparseformula converts the formula into unparsed internal format. XSLPvalidformula then checks forward from the last invalid token and tries to identify it as an internal function (followed by a left bracket) or as a column (otherwise). If it cannot be identified, the checking stops with an error message. Otherwise, the token type and value are updated and the procedure continues.