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I have a .map file which contains x-ray crystallography data of a bacteriophage. The format of the file is CCP4. I can open the file using VMD. However, I am unable to get the xyz co-ordinates. It shows the following error when I click on the option of saving data in xyz format:

`No timesteps selected; trajectory file will not be written.'

It is a big file of 64MB.

The file I am referring to may be downloaded at:

Can't we save xyz co-ordinates for CCP4 files? Or is it possible to extract any other form of data?

I am new to VMD and these formats. Any help would be appreciated.

share|improve this question
It's an electron density map. What xyz coordinates do you want to extract? – marcin Jul 3 '15 at 11:05

Just Download and Install: CCP4: Software for Macromolecular Crystallography

share|improve this answer
CCP4 is a suite of 200+ programs, just installing it won't solve any problem. – marcin Oct 14 '15 at 10:31

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