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XSLPparseformula

Purpose

Parse a formula written as an unparsed array of tokens into internal parsed (reverse Polish) format

Synopsis

int XPRS_CC XSLPparseformula(XSLPprob Prob, int *inType, 
               double *inValue, int *nToken, int *Type, double *Value);

Arguments

Prob	The current SLP problem.
inType	Array of token types providing the unparsed formula.
inValue	Array of values corresponding to the types in inType.
nToken	Address of an integer to receive the number of tokens in the parsed formula (not counting the terminating XSLP_EOF token). May be NULL if not required.
Type	Array of token types providing the parsed formula.
Value	Array of values corresponding to the types in Type.

Example

Assuming that x and y are already defined as columns with index iX and iY respectively, the following example converts the formula "sin(x+y)" into internal parsed format, and then writes it out as a sequence of tokens.

int n, iSin, iX, iY;
int inType[7], Type[20];
double inValue[7], Value[20];
n = 0;
XSLPgetindex(Prob, XSLP_INTERNALFUNCNAMESNOCASE,
             "SIN", &iSin);
Type[n] = XSLP_IFUN;  Value[n++] = iSin;
Type[n++] = XSLP_LB;
Type[n] = XSLP_COL;  Value[n++] = iX;
Type[n] = XSLP_OP;  Value[n++] = XSLP_PLUS;
Type[n] = XSLP_COL;  Value[n++] = iY;
Type[n++] = XSLP_RB;
Type[n++] = XSLP_EOF;
XSLPparseformula(Prob, inType, inValue, 
                 NULL, Type, Value);
printf("\n");
for (n=0;Type[n] != XSLP_EOF;n++) {
  XSLPitemname(Prob, Type[n], Value[n], Buffer);
  printf(" %s", Buffer);
}

Further information

For possible token types and values see the chapter on "Formula Parsing".