fix : calculate dos_smearing without reading DOS first

[wenfei-li]

The reason behind this bug is that in calculating DOS_smearing, the program first takes the calculated DOS as input:

			 for(int i=0;i<number;i++)
			 {
				 in >> energy[i] >> dos[i];
			 }
			 if(!in.eof())
			 {
				 //std::cout<<"\n Read Over!"<<std::endl;
			 }
			 in.close();

This might have something to do with the input buffer. Also, it is bad practice to use the output file of the program as input file.
The way to fix this is to save the array that stores DOS and use that in calculating DOS_smearing, instead of reading from DOS.

[caic99]

Hi @wenfei-li ,
Thank you for your work!
You can attach the detail of bug in PR description (exactly the thing you replied in #746 ), and summarize this bug in PR subject.

[wenfei-li]

Hi @wenfei-li , Thank you for your work! You can attach the detail of bug in PR description (exactly the thing you replied in #746 ), and summarize this bug in PR subject.

not sure how to do that :P