feasible descent direction

基本解釋

After finite iterations, the iteration point gets into the feasible set and the master direction is a feasible direction of descent.
有限次迭代后，迭代點(diǎn)進(jìn)入可行集且主方向是一可行下降方向。
At each iteration, the method uses a linearly constrained positive semidefinite quadratic problem to generate a feasible descent direction.
在每次迭代時(shí)，這種方法都利用一種線性約束半正定二次問題來產(chǎn)生一個(gè)合理的下降方向；
So at every nonstationary point there exists at least one feasible descent direction, every iterate generated by the methods is feasible so long as the initial iterate is feasible .
這樣在每一個(gè)非穩(wěn)定點(diǎn)處至少存在一個(gè)可行的下降方向，在初始點(diǎn)是可行點(diǎn)的條件下，此算法產(chǎn)生的每一個(gè)迭代點(diǎn)都是可行點(diǎn)。