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<DIV><FONT size=2>Hi all</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>I am doing transmission calculation by pwcond.x. I have 2
question about the efficiency of it.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2>(1) The most severe problem was that </FONT><FONT size=2>I
felt the transmission calculation by pwcond.x was too </FONT></DIV>
<DIV><FONT size=2>slow. As an example, the </FONT><FONT size=2>system contains a
</FONT><FONT size=2>6-atom lead and about 100-atom scattering region.
T</FONT></DIV>
<DIV><FONT size=2>he kx and ky was </FONT><FONT size=2>8 and 1 respectively. The
input file for pwcond.x is as follows:</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>----------------</FONT></DIV>
<DIV><FONT size=2>&inputcond<BR>
outdir='./outdir',<BR> prefixl='lead'<BR>
prefixs='cen',<BR> tran_file='trans.0'<BR>
ikind = 1,<BR> energy0=2.0d0,<BR>
denergy=-0.2d0<BR> ewind=4.d0,<BR>
epsproj=1.d-7,<BR> nz1 = 10,<BR> /<BR>
5<BR> 0.0000000 0.0000000
0.2500000<BR> 0.1250000 0.0000000
0.5000000<BR> 0.2500000 0.0000000
0.5000000<BR> 0.3750000 0.0000000
0.5000000<BR> -0.5000000 0.0000000
0.2500000<BR> 21<BR>------------------</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>It took about 1 hour to get a transmission value for a certain
energy on a 8-node parallel cluster</FONT></DIV>
<DIV><FONT size=2>with 1 G memory, 2.5 GHz CPU and infiniband. Is it a
reasonable one?</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>(2) I notice that the time needed for the transmission is
linear proportional to the number of </FONT></DIV>
<DIV><FONT size=2>energy points. That means if the time needed for a single
energy point is 1 hour, it will take </FONT></DIV>
<DIV><FONT size=2>20 hours for 20 energy points. This is different with some
other scientific softwares. Is it natural</FONT></DIV>
<DIV><FONT size=2>for pwcond.x?</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Thank you in advance</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Best wishes</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Wang</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>------------------------------------<BR>王秦镜，复旦大学物理系研究生<BR>Wang
Qinjing, Physics Department, <BR>Fudan University</FONT></DIV></BODY></HTML>