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Groups32 has a mechanism to search the groups of orders 132 to find those with given generators satisfying given relations, or to find groups that contain subgroups with the given finite presentation. The algorithm used is quite literal: All group elements are substituted for the generators, and then the orders and relations are checked. A "shortcut" evaluation is used: Once a condition is found to be FALSE, no subsequent conditions are checked.
This is the slowest procedure in Groups32. Direct assembly language coding of G* (and 8 other words) does result in a dramatic speedup of SEARCH.
Here is how SEARCH can be used to identify the dihedral groups, which are groups with two generators, x and y, with x of order 2, but the order of y is not specified. The defining relation is xy = y'x, where ' indicates inverse. The prompted input in the following example is from the command completion user interface that I describe in the next section.
Enter distinct generators as a string e.g. RS means two generators R and S Generators: xyDo you want these to generate the entire group? (y or n) Y
Enter the exact order for each generator. Press Enter for no order specified X is of order 2 Y is of order
A relation is of the form LHS = RHS Put in LHS RHS or LHS ( if RHS is e )
LHS RHS >> xy y'xGenerators: XY Orders: X= 2
RELATIONS: XY = Y'X
 Pressing ESC will abort the search 
2 group order = 2 X = B Y = B
5 group order = 4 X = C Y = B
8 group order = 6 X = D Y = B
13 group order = 8 X = E Y = B
18 group order = 10 X = F Y = B
22 group order = 12 X = G Y = B
27 group order = 14 X = H Y = B
40 group order = 16 X = I Y = B
47 group order = 18 X = J Y = B
52 group order = 20 X = K Y = B
58 group order = 22 X = L Y = B
69 group order = 24 X = M Y = B
78 group order = 26 X = N Y = B
86 group order = 28 X = O Y = B
92 group order = 30 X = P Y = B
111 group order = 32 X = B Y = D
The group of quaternionic units (order 8) can be presented as a group with three generators, a, b, c, and relations ab = c, bc = a, ca = b. The following chart shows the timing for the SEARCH command using different Forth implementations and computers.
Timing for Search 

Groups32 ver 7.0 // Win32Forth high level 
1308270 ms 
Groups32 ver 7.0 // Win32Forth assembly language 
51300 ms 
Groups32 ver 7.0 // SwiftForth 
307656 ms 
Groups32 ver 6.4g // Gforth LINUX 
1794000 ms 
Groups32 ver 6.4g // Gforth on Internet 
2700000 ms 
The entry marked Win32Forth assembly language replaces just nine words by assembly language equivalents  the increase in speed is remarkable.
The entries for Gforth compare a LINUX version of Forth on a personal computer with the timing for the same version (running on a SUN server) accessed via Telnet on the Internet.
Notice that the fastest timing (about 1 min) is for a personal computer using assembly language coding of a few timecritical commands, and the slowest, using the Internet, is about 45 min. With the exception of the entry marked "Internet", the computer used has a Pentium III processor running at 450 Mhz.
The process of searching through a collection of groups to find those with a given set of generators and relations is inherently timeconsuming. This does not preclude the possibility that a better algorithm will make a major improvement.
John J. Wavrik, "Evolution of a Computer Application  Search," Convergence (December 2004)
Journal of Online Mathematics and its Applications