On 31/03/17 13:19, Stephen P. Molnar wrote: > I have a block of data extracted from a quantum mechanical calculation:
How is this data stored? On paper? In a database? In XML? A CSV file? Plain text? The answer to that will go a long way to pointing you in the right direction for a solution. > CARTESIAN COORDINATES (A.U.) > ---------------------------- > NO LB ZA FRAG MASS X Y Z > 0 C 6.0000 0 12.011 -3.265636 0.198894 0.090858 > 1 C 6.0000 0 12.011 -1.307161 1.522212 1.003463 > 2 C 6.0000 0 12.011 1.213336 0.948208 -0.033373 > 3 N 7.0000 0 14.007 3.238650 1.041523 1.301322 > 4 C 6.0000 0 12.011 -5.954489 0.650878 0.803379 > 5 C 6.0000 0 12.011 5.654476 0.480066 0.013757 > > where the number of lines depends upon the molecule being considered. > > I want to extract the block of data starting on line 4 and column 4. A block of data needs a start and end. Where is the end? Also which of the above lines is line 4? I'd read it as the one starting the actual raw data values. But it could be the 4th line of values that you want? It might help to know the OS you are using too because Unix in particular has some OS level tools that might simplify preparing the data. -- Alan G Author of the Learn to Program web site http://www.alan-g.me.uk/ http://www.amazon.com/author/alan_gauld Follow my photo-blog on Flickr at: http://www.flickr.com/photos/alangauldphotos _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor