Initializing help system before first use

# problem.delRows

Purpose
Delete rows from a matrix.
Topic areas
Problem Creation, Optimizer
Synopsis
`problem.delRows(rowind)`
Argument

rowind: list[constraint] | An integer array containing the rows to delete.

Further information
1. After rows have been deleted from a problem, the numbers of the remaining rows are moved down so that the rows are always numbered from 0 to ROWS-1 where ROWS is the problem attribute containing the number of non-deleted rows in the matrix.
2. If the problem has already been optimized, or an advanced basis has been loaded, and you delete a row for which the slack column is non-basic, the current basis will no longer be valid - the basis is "lost". If you go on to re-optimize the problem, a warning message is displayed ( 140) and the Optimizer automatically generates a corrected basis.
You can avoid losing the basis by only deleting basic rows (see problem.getBasis), bringing a non-basic row into the basis first if necessary (see problem.getPivots and problem.pivot).
3. This function cannot be called while the current problem is being solved or when it is in an interrupted state. Use problem.postSolve to restore the problem to a non-solving state.
4. Argument rowind may contain either xpress.constraint objects or integer indices.
Related topics
problem.addRows, problem.delCols, problem.getBasis, problem.getPivots, problem.pivot.
Parent Topic Xpress problem object methods

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