Volume 1 Chapter 5 Numeric Searches in Graphics QUEST3D

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5.1.3 Screen Searches

Both database screens and query screens have been discussed in chapter 2. A complete list of the 682 1D and 2D bit screens is given in Appendix 1 of the printed documentation but note that normally a user would assign bit screens only in the range 1-155.

The command SCREEN (or SCRE) and the keyword *BTEST (or *BTES) are available for screen searches:

For (a)-(c) the individual screens n1, n2, n3, n4 etc. are linked by the logical operator .AND. Thus all must be satisfied for a hit to be registered.

For (d) the individual screens n1, n2, n3, n4 etc. are linked by the logical operator .OR.

Screen assignments and *BTEST constructions are made using the SCREEN sub-menu shown below.

Full details of SCREEN and *BTEST are given in chapter 9 of Vol.2.

Ex.1 Suppose we wish to use the following bit screeens: 34 entry contains uncorrected errors

49 neutron studies

Both screens must be satisfied for a hit to be registered, ie. error-free neutron studies.

Ex.2 Suppose we wish to find all hexagonal and rhombohedral entries (bit screens 107 and 109 resp.)

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Volume 1 Chapter 5 Chemical Formula Searches in Graphics QUEST3D.