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XPRBnewvar

Purpose

Declare a single variable.

Synopsis

XPRBvar XPRBnewvar(XPRBprob prob, int type, const char *name, double bdl, double bdu);  

Arguments

prob  

Reference to a problem.

type  

The variable type, which may be one of:

XPRB_PL	continuous;
XPRB_BV	binary;
XPRB_UI	general integer;
XPRB_PI	partial integer;
XPRB_SC	semi-continuous;
XPRB_SI	semi-continuous integer.

name  

The variable name (of unlimited length). May be NULL if not required.

bdl

The variable's lower bound

bdu

The variable's upper bound

Return value

Reference to the new variable if function executed successfully, NULL otherwise.

Example

XPRBprob prob;
XPRBvar x1, x2;
 ...
x1 = XPRBnewvar(prob, XPRB_UI, "abc3", 1, 100);
x2 = XPRBnewvar(prob, XPRB_SC, "klm2", 0, 20);

This defines an integer variable x1, taking values between 1 and 100, with the name abc3, and a semi-continuous variable x2, taking the value 0 or values between 1 and 20, with the name klm2.

Further information

1. The creation of a variable in BCL involves not only its name but also its type and bounds (which may be infinite, defined by the corresponding Xpress-MP constants). The function returns the BCL reference to the variable (i.e. a model variable). If the indicated name is already in use, BCL adds an index to it. If no variable name is given, BCL generates a default name starting with VAR. If a partial integer, semi-continuous, or semi-continuous integer variable is being created, the integer or semi-continuous limit (i.e. the lower bound of the continuous part for partial integer and semi-continuous, and of the semi-continuous integer part for semi-continuous integer) is set to the maximum of 1 and bdl. This value can be subsequently modified with the function XPRBsetlim.

2. The lower and upper bounds may take values of -XPRB_INFINITY and XPRB_INFINITY for minus and plus infinity respectively.