Purpose: To form structures having planes of symmetry by reflecting part
of the structure in the coordinate planes, and to set flags so that
symmetry is utilized in the solution.
Card:
Cols Parameter
----------------------
1- 2 GX
3- 5 I1
6-10 I2
11-80 blank
Parameters:
Integers
(I1) - Tag number increment.
(12) - This integer is divided into three independent digits, in
columns 8, 9, and 10 of the card, which control reflection
in the three orthogonal coordinate planes. A one in column
8 causes reflection along the X-axis (reflection in Y, Z
plane); a one in column 9 causes reflection along the Y-axis;
and a one in column 10 causes reflection along the Z axis.
A zero or blank in any of these columns causes the corres-
ponding reflection to be skipped.
Decimal Numbers
The decimal number fields are not used.
No. of Planes Matrix Fill Factor
of Symmetry Storage Time Time
0 N^2 N^2 N^3
1 N^2/2 N^2/2 N^3/4
2 N^2/4 N^2/4 N^3/16
3 N^2/8 N^2/8 N^3/64
The matrix factor time represents the optimum for a large matrix
factored in core. Generally, somewhat longer times will be observed.
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