| DiaCanvas2 Reference Manual |
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DiaExpression — A linear expression, part of a DiaConstraint.
struct DiaExpression; void dia_expression_add (DiaExpression **expr, DiaVariable *var,gdouble c); void dia_expression_add_expression (DiaExpression **expr, DiaExpression *expr2); void dia_expression_times (DiaExpression *expr,gdouble c); void dia_expression_free (DiaExpression *expr);
DiaExpression is a small data structure that holds a linear expression. The DiaConstraint class holds a DiaExpression. It is advised to use the DiaConstraint function rather than those functions directly.
struct DiaExpression {
guint len;
struct _DiaExpressionElem
{
DiaVariable *variable;
gdouble constant;
} elem[1];
};
void dia_expression_add (DiaExpression **expr, DiaVariable *var,gdouble c);
Add "c * var" to expr (expr = expr + (c * var)).
| expr : | |
| var : | |
| c : |
void dia_expression_add_expression (DiaExpression **expr, DiaExpression *expr2);
Add expr2 to expr (expr = expr + expr2).
| expr : | |
| expr2 : |
void dia_expression_times (DiaExpression *expr,gdouble c);
Multiply expr with value c (expr = expr * c).
| expr : | |
| c : |
| << DiaVariable | DiaConstraint >> |