Hi,guys,<br>I am not sure am I supposed to ask for help here or not. But I do need your guys&#39; help to give me some hint solving this problem.<br>I have a parallel fortran code which is written by us. It seems like working well but actually the output from 1 node to 5 nodes are the same(the results I think are correct).When I am using more than 6 nodes, the output is different,which I think is wrong.<br>
For example,the following lines are the output from 1(or 2) node calculation and 6 nodes calculation. Look at the data. The atomic positions are the same. But the order of atoms are different. Why dose this happen? Why the results are different with 5 nodes and 6 nodes?<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; atom type&nbsp;&nbsp;&nbsp; atomic position<br>&nbsp;&nbsp;&nbsp; 1&nbsp;&nbsp;Al&nbsp; &nbsp; 0.0000&nbsp; &nbsp; 0.0000&nbsp; &nbsp;-1.8869<br>
&nbsp; &nbsp; 2&nbsp;&nbsp;O&nbsp; &nbsp; -1.6539&nbsp; &nbsp; 0.1249&nbsp; &nbsp;-1.0842<br>
&nbsp; &nbsp; 3&nbsp;&nbsp;O&nbsp; &nbsp;&nbsp;&nbsp;0.7188&nbsp; &nbsp;-1.4947&nbsp; &nbsp;-1.0842<br>
&nbsp; &nbsp; 4&nbsp;&nbsp;O&nbsp; &nbsp;&nbsp;&nbsp;0.9351&nbsp; &nbsp; 1.3699&nbsp; &nbsp;-1.0842<br>
&nbsp; &nbsp; 5&nbsp;&nbsp;Al&nbsp; &nbsp; 2.3727&nbsp; &nbsp;-1.3699&nbsp; &nbsp;-0.2816<br>
&nbsp; &nbsp; 6&nbsp;&nbsp;Al&nbsp; &nbsp;-2.3727&nbsp; &nbsp; 1.3699&nbsp; &nbsp; 0.2816<br>
&nbsp; &nbsp; 7&nbsp;&nbsp;O&nbsp; &nbsp;&nbsp;&nbsp;1.6539&nbsp; &nbsp;-0.1249&nbsp; &nbsp; 1.0842<br>
&nbsp; &nbsp; 8&nbsp;&nbsp;O&nbsp; &nbsp; -0.7188&nbsp; &nbsp; 1.4947&nbsp; &nbsp; 1.0842<br>
&nbsp; &nbsp; 9&nbsp;&nbsp;O&nbsp; &nbsp; -0.9351&nbsp; &nbsp;-1.3699&nbsp; &nbsp; 1.0842<br>
&nbsp; &nbsp;10&nbsp;&nbsp;Al&nbsp; &nbsp; 0.0000&nbsp; &nbsp; 0.0000&nbsp; &nbsp; 1.8869<br>
<br>
&nbsp; &nbsp; 1&nbsp;&nbsp;Al&nbsp; &nbsp; 0.0000&nbsp; &nbsp; 0.0000&nbsp; &nbsp;-1.8869<br>
&nbsp; &nbsp; 2&nbsp;&nbsp;O&nbsp; &nbsp; -1.6539&nbsp; &nbsp; 0.1249&nbsp; &nbsp;-1.0842<br>
&nbsp; &nbsp; 3&nbsp;&nbsp;O&nbsp; &nbsp;&nbsp;&nbsp;0.7188&nbsp; &nbsp;-1.4947&nbsp; &nbsp;-1.0842<br>
&nbsp; &nbsp; 4&nbsp;&nbsp;Al&nbsp; &nbsp; 0.9351&nbsp; &nbsp; 1.3699&nbsp; &nbsp;-1.0842<br>
&nbsp; &nbsp; 5&nbsp;&nbsp;O&nbsp; &nbsp;&nbsp;&nbsp;2.3727&nbsp; &nbsp;-1.3699&nbsp; &nbsp;-0.2816<br>
&nbsp; &nbsp; 6&nbsp;&nbsp;O&nbsp; &nbsp; -2.3727&nbsp; &nbsp; 1.3699&nbsp; &nbsp; 0.2816<br>
&nbsp; &nbsp; 7&nbsp;&nbsp;O&nbsp; &nbsp;&nbsp;&nbsp;1.6539&nbsp; &nbsp;-0.1249&nbsp; &nbsp; 1.0842<br>
&nbsp; &nbsp; 8&nbsp;&nbsp;Al&nbsp; &nbsp;-0.7188&nbsp; &nbsp; 1.4947&nbsp; &nbsp; 1.0842<br>
&nbsp; &nbsp; 9&nbsp;&nbsp;Al&nbsp; &nbsp;-0.9351&nbsp; &nbsp;-1.3699&nbsp; &nbsp; 1.0842<br>
&nbsp; &nbsp;10&nbsp;&nbsp;Al&nbsp; &nbsp; 0.0000&nbsp; &nbsp; 0.0000&nbsp; &nbsp; 1.8869<br><br>Your help is really appreciated,<br>Wayne<br>