EMRESOL

Function of the program:   Calculate the resolution of the EM reconstruction. The function is similar to the program EMSF of Dr. Tim Baker.

Purpose of the program:   The program EMSF was under VMS (now may has a UNIX version) and the output of EMSF was not easy to understand. The bin shell range was listed in reciprocal value. In order to work under UNIX and has an easy-understand output, Ricardo Bernal wrote the original codes of EMRESOL. I modified it a lot to simplify the codes and use the volume of reciprocal space to divide each bin shell so that each bin shell has same number of structure factors. The purpose of doing so is to make all the bin shell has same statistic weight. Later, the program has also been modified to support GRACE plot. The GRACE plot can be view by the UNIX software Xmgrace to see the curve directly under UNIX. Previously, the output ASCII file need to be transfer to Windows and use Excel to plot the curve. The new version also support to use the Xmgrace to directly generate PostScript or JPEG image plot. In addition, it can append resolution results to previous one so that people can compare the resolution results from different reconstructions.

Usage of the program:

• Usage: emresol [option] map1.asf map2.asf

• Options:

  Options	explanations
  -a	append instead of overwrite the output file
  -b Number_of_bin	set the resolution bin number,default is 80
  -h Highest_Resolution	set the highest resolution, default is 5.0A
  -l Lowest_Resolution	set the lowest resolution, default is 100.0A
  -c Cutoff_SF	set the cutoff of the SF, default is 0.0
  -o Output_filename	set the output file name, default is emresol.out
  -p Plot_filename	set the plot file name, default is emresol_plot.out
  -s legend_title	set the plot file name, default is emresol_plot.out
  -t Plot_type	set the plot type, default is 1 0: ASCII plot; 1: GRACE plot
  -v	give verbose output when running, default is not

• Options only available for command line:

  Options	explanations
  -i	run program interactively
  -m maxref	set the maximum SF number, default is 5000000
  -g	show Y axis grid lines, only available for GRACE plot
  -q	hide the phase plot, only available for GRACE plot
  -k tick_minor_step	set X axis tick minor step, 0.5 = 0.5A, 1 = 1A, 2 = 2A(default) only available for GRACE plot

• Example for EMRESOL:

  Run it interactively	emresol -i
  Run it by command line	emresol -b 40 -h 10 -l 50 map1.asf map2.asf
  Plot as XMGRACE plot	emresol -b 40 -h 10 -l 50 -p resolution.agr -t 1 map1.asf map2.asf

BUG REPORT: If you meet any bugs or problems of the programs, please email me at xc@purdue.edu.