Change a single coefficient in the matrix
| 1059 | |
| 1060 | // Change a single coefficient in the matrix |
| 1061 | void Highs::changeCoefficientInterface(const HighsInt ext_row, |
| 1062 | const HighsInt ext_col, |
| 1063 | const double ext_new_value) { |
| 1064 | HighsLp& lp = model_.lp_; |
| 1065 | // Ensure that the LP is column-wise |
| 1066 | lp.ensureColwise(); |
| 1067 | assert(0 <= ext_row && ext_row < lp.num_row_); |
| 1068 | assert(0 <= ext_col && ext_col < lp.num_col_); |
| 1069 | const bool zero_new_value = |
| 1070 | std::fabs(ext_new_value) <= options_.small_matrix_value; |
| 1071 | changeLpMatrixCoefficient(lp, ext_row, ext_col, ext_new_value, |
| 1072 | zero_new_value); |
| 1073 | // Deduce the consequences of a changed element |
| 1074 | // |
| 1075 | // ToDo: Can do something more intelligent if element is in nonbasic |
| 1076 | // column |
| 1077 | // |
| 1078 | const bool basic_column = |
| 1079 | this->basis_.col_status[ext_col] == HighsBasisStatus::kBasic; |
| 1080 | // |
| 1081 | // For now, treat it as if it's a new row |
| 1082 | invalidateModelStatusSolutionAndInfo(); |
| 1083 | |
| 1084 | if (basic_column) { |
| 1085 | // Basis is retained, but is has to be viewed as alien, since the |
| 1086 | // basis matrix has changed |
| 1087 | this->basis_.was_alien = true; |
| 1088 | this->basis_.alien = true; |
| 1089 | } |
| 1090 | |
| 1091 | // Determine any implications for simplex data |
| 1092 | ekk_instance_.updateStatus(LpAction::kNewRows); |
| 1093 | } |
| 1094 | |
| 1095 | HighsStatus Highs::scaleColInterface(const HighsInt col, |
| 1096 | const double scale_value) { |
nothing calls this directly
no test coverage detected