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<span>hello!
</span></div><div><span><br></span></div><div><span style="font-family: 微软雅黑;">I am trying to use epsgd compute matrix's one smallest eigenvalue. And I find a strang thing. There are two matrix A(900000*900000) and B(90000*90000). While solve A use 371 iterations and only 30.83s, solve B use 22 iterations and <span style="line-height: 1.6;">38885s! What could be the reason for this? Or what can I do to find the reason?</span></span></div><div><span style="line-height: 1.6; font-family: 微软雅黑;"><br></span></div><div><span style="line-height: 1.6; font-family: 微软雅黑;">I use" </span><font color="#d4d4d4" face="Consolas, Courier New, monospace"><span style="line-height: 19px; white-space: pre; color: rgb(36, 36, 36); font-family: 微软雅黑; background-color: rgb(255, 255, 255);">-eps_type gd -eps_ncv 300 -eps_nev 3 -eps_smallest_real ". </span></font></div><div><font color="#d4d4d4" face="Consolas, Courier New, monospace"><span style="line-height: 19px; white-space: pre; color: rgb(36, 36, 36); font-family: 微软雅黑; background-color: rgb(255, 255, 255);">And there is one difference I can tell is matrix B has many small value, whose absolute value is less than 10-6. Could this be the reason?</span></font></div>
<div><span style="line-height: 1.6;"><br></span></div><div><span style="line-height: 1.6;">Thank you!</span></div><div><span><br></span></div>
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<div style="font-family:"微软雅黑"; font-size: 14px; color:#000000">Runfeng <span style="line-height: 22.4px;">Jin</span><span style="line-height: 22.4px;"> </span></div>
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