Hi Sandeep,

This error indicates that the mrc file data values are all zero. The error occured when making the histogram that is shown in the Volume Viewer dialog, when it was trying to scale it to fit the width of the dialog. Of course, our code should not generate an error in this case. I will fix it for the next release.

If you will be opening mrc files that may be all zero you can change chimera/share/VolumeViewer/histogram.py line 26

hscale = float(cheight) / max_height

to

if max_height == 0: hscale = 1 else: hscale = float(cheight) / max_height

Then you will not get any error and the histogram will display correctly.

Thanks for pointing out this problem.

I am not familiar with pdb2mrc so I do not know why it is generating a volume consisting of all zeros.

Tom

Date: Wed, 30 Jun 2004 21:33:12 -0600 From: Sandeep N Seshadri sandeep@nmsu.edu To: chimera-dev@cgl.ucsf.edu Subject: [chimera-dev] regd error when opening a .mrc file

i am getting the following error when i try to open a .mrc file . i generated a .pdb file and use a pdb2mrc to generate a .mrc file . i tried opening the .pdb file it works fine but when i try to open the .mrc file it gives the error.

if anyone has any idea on why this error occurs please let me know

thanks sandeep

Error while processing test-helix.mrc: ZeroDivisionError: float division (see reply log for Python traceback info) Traceback (most recent call last): File "/home/sandeep/chimera/share/__main__.py", line 56, in ? value = chimeraInit.init(sys.argv) File "/home/sandeep/chimera/share/chimeraInit.py", line 275, in init prefixableType=1) File "/home/sandeep/chimera/share/chimera/__init__.py", line 886, in open models = func(filename, *args, **kw) File "/home/sandeep/chimera/share/VolumeViewer/ChimeraExtension.py", line 30, in open_cb d.add_data_sets([g]) File "/home/sandeep/chimera/share/VolumeViewer/__init__.py", line 175, in add_data_sets self.redisplay_cb() File "/home/sandeep/chimera/share/VolumeViewer/__init__.py", line 459, in redisplay_cb self.show_using_dialog_settings(self.focus_region) File "/home/sandeep/chimera/share/VolumeViewer/__init__.py", line 380, in show_using_dialog_settings tp.update_histograms(data_region) File "/home/sandeep/chimera/share/VolumeViewer/__init__.py", line 1142, in update_histograms cw.update_histogram(data_region, read_matrix, self.dialog.message) File "/home/sandeep/chimera/share/VolumeViewer/__init__.py", line 1465, in update_histogram h.show_data(Numeric.log(s.counts + 1)) File "/home/sandeep/chimera/share/VolumeViewer/histogram.py", line 26, in show_data hscale = float(cheight) / max_height ZeroDivisionError: float division