Merge pull request #1 from bareid/master

Created a new notebook.
Error obtained by model-fiting A param is nw approximately equal to error value obtained by the average analytical sig_b value from Monte Carlo
Using the meshgrid generated using sdss params to plot convolved devauc on loglog scale but values very close to zero so -inf and can not plot.; may need to use our own xgrid ygrid, and somehow relate this to a linespace of r values as in aopt=0 and aopt=1 plots
resulting gaussian from table values not normalized
minor fix
commit
only  symmetrical variance matrices result in a circular profile
changed gaussian addition
the double loop for plotting de vauc too large 1361*2048 run by external script
added plots resulting from dev plot
attempted to open data file by pyfits