# ediffana/edensgrid

Edit: all calculations on non-centrosymmetric structures are wrong. I am working on a solution.
Edit 11/10/2010: Fixed in 0.3 version available on the repo.

Two new packages made it in the fedora repos. Not in centos, I used featured in fortran and python not available in the versions of gfortran and subprocess 🙁

edensgrid calculates (difference) electron density grids. The input is a list 3 fcf file from shelx, the output, an ascii file with the 3D array flattened (2D slices separated by two blank lines). The fourier transform is done with fftw3.

ediffana calculates some stats and plot the distribution of the difference electron density maps (like in wingx). As this is the difference between the model and experimental data, the result should be a normal distribution. Otherwise, you are missing something in your model. The input is a cif file and a electron density map from edensgrid. The ouput is a gnuplot graph or a matplotlib output (default) with some stats in the terminal.

To launch ediffana, just type “ediffana” and your filename without extension, you can put multiple filenames and the graphs will be stacked in one window.

To install them, just yum ediffana and/or edensgrid
For the usage, in a terminal, just type ediffana ‐‐help or edensgrid ‐‐help, the are a few more options.

 #### m104i #### mean: -0.0000 median: 0.0029 s^2: 0.0657 min: -0.3155 max: 0.6505 Skewness: -0.013 (normal: 0) Kurtosis: 1.440 (normal: 0) Normal test: 2.72e+04, 0.00 Report of linear regression of the normal probability plot: Slope = 0.9948, Intercept = -0.0000 r2 = 0.990 partial fit (left side): Slope = 1.3925, Intercept = 0.0480 r2 = 0.985 partial fit (right side): Slope = 2.2717, Intercept = -0.1862 r2 = 0.950 

If there is any problem, feel free to talk about it in a comment or send me an email to pascal22p@parois.net. These are not heavily tested yet.