[Help-glpk] two question about LP with GLPK

[George Andrew]

Hi, Andrew and other guys,

 
I have 2 questions about LP with glpk.
1) How to deal with problems with constraint boundary disturbance quickly. For 
example, originally I have L_i<x_i<U_i (i=1,...n), when I get the answer of x, 
how can I get another answer with glpk quickly to L_i-e<x_i<U_i+e,where e is a 
number(such as 0.2 or 0.5)?
 
2) If x_i can only be some real number defined in a known table which satisfy 
L_i<x_i<U_i. For example 1<x_1<2 and x_1 can only possibly be a number in the 
table of {1.1,1.13,1.5,1.77,1.93}.The table has no special structure other than 
ascending sorted. How can I deal with such problems in glpk?
 
Thanks.
George