Random access file

File handling statements allow the manipulation of sequential and random access files. (Since there is considerable variation from one system to the next, the following information is given in general terms only.) Devices are treated... 

All setup data and results are stored in Data Resource Files rather than standard sequential or random access files. This has turned out to be a key feature contributing to a flexible and low maintenance system. These are ASCII files which can be typed to the screen, printed, or edited with a word processor. They contain information organized by variable name, value, and units. The following is an example of a data resource file ... 

Problems may arise if the lengths of the inverted lists differ. This may be because certain wavenumbers are more typical than others or certain chemical structures appear more often, for example, -C-C- is more frequent than -C=C-. The solution to this problem is the appHcation of Hash coding algorithms the key is coded by a random number that is then stored in a random access file. 

PVFM polyvinyl formal RAF random access file... 

A copy (5V4 inch floppy disk) of a menu-driven computer program to calculate Gibbs free energy of formation and change in Gibbs free energy for reactions (including random access data file of compound coefficients) is available for a nominal fee. For details, contact C. L. Yaws, Dept, of Chem. Eng. Lamar University, P.O. Box 10053, Beaumont, Texas 77710, USA. 

File—External (physical) only may be sequential or random access. 

A computer program, containing the data for all compounds, is available for a nominal fee (Carl L. Yaws, Box 10053, Lamar University, Beaumont, TX 77710, phone/FAX 409-880-8787). The computer program (random data file) is in ASCII which can be accessed by other software. 

The standard deviation of each scanner reading has been estimated to be 0. 7 when using a scale of 0-255 units, and the positional accuracy of the instrument is claimed to be 2pm. Data from the microdensitometer are stored in binary format on magnetic tape as an array, typical dimensions being 600 x 600. Prior to analysis the data are reconverted to integer format and copied into a random-access disc file. 

THIS PROGRAM CONTAINS A ROUTINE TO GAIN RANDOM ACCESS THE DATA FILE. THIS ENABLES ANY COMPONENT SUB-FILE TO BE PICKED OUT FOR EDITING. IT DOES THIS BY WRITING THE VALUES INTO A SECOND FILE (DATA FILE 2) UNTIL THE REQUIRED SUB-FILE IS REACHED, THE DATA IN THE "... 

For efficiency purposes, we need to put our FASTA-formatted sequences into another format. The author has developed a file format, the Sequence Database format (SDB), that allows for fast random access to multiple sequences stored in a single file. See Note 2b for descriptions of the command-line utilities available (as part of the Mercator distribution) for creating and accessing SDB files. We will use the fa2sdb utility to put our softmasked genomes into SDB format. 

The file BND/YY/B, which after execution of LMTO (if NOEVC = 1) contains the eigenvalues and ti characters, is a random (direct) access file. This file organisation very often causes problems when LMTOPACK is implemented on machines other than Burroughs B7800. The problem is that the Burroughs, for which the programmes were written, allows sequential write and subsequent random read in a file with fixed record length, while most other machines do not. 

Example VIC If a company stored all of their folders in a file cabinet alphabetically, then an employee would be able to find any folder in the file with roughly equal speed (randomly accessible). However, if the folders were stored flat in nonalphabetized order in a box, then the employee would have to sequentially search for the desired folder in the box. These filing systems are analogous to the randomly accessible and sequentially accessible memory storage units. 

More advanced streaming properties may require a server to properly stream. The server controls how the stream is being sent and may be able to compensate for network traffic problems, allow variable bit-rate playback, and let the listener randomly access different parts of the file (instead of listening in a linear fashion). Streaming media servers are sold by a number of streaming format companies and must be installed on the sending computer. This means that you may need to find an ISP that specializes in streaming media to distribute your media or work with your local ISP to get the proper server software installed. 

PYI —Collection of records that normally consist of matching types of fields. Records in a file may be accessed sequentially (the entire file must be read until the needed record is reached) or randomly (the record contains a key field, which determines its physical location in storage). 

FILE 1 iUNFORMATTED,TYPE=RANDOM (DIRECT) ACCESS, ... 

The upshot is that, if the repulsion integrals are to be stored then the m (at most) permutationally distinct integrals will be stored together with their labels and any code which accesses the file so generated must assume that the integrals occur in random order. 

For direct access to any record in response to a random enquiry, calculation of where to find the record within the file is also very simple and very quick. 

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