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Proposed revised American standard code for information interchange


CLP-the Cornell list processor

Presented in this paper are the highlights of CLP, a teaching language which has been employed at Cornell University and was constructed to serve as a means of introducing simulation and other list-processing concepts. The various …

Algorithm 253: [F2]: Eigenvalues of real symmetric matrix by the QR method


Alogorithm 252 [Z]: vector coupling or Clebsch-Gordan coefficients


Algorithm 254: [F2]: Eigenvalues and eigenvectors of a real symmetric matrix by the QR method


Certification of algorithm 21 [S17]: Bessel function for a set of integer orders


Remark on algorithm 231 [F1]: matrix inversion


The use of FORTRAN in subroutines with COBOL main programs

By using the proper COBOL coding techniques and accounting for differences in storage allocation and library routines between the two languages, it is possible to write FORTRAN IV subroutines that may be called from COBOL main …

Data input by question and answer

A data input scheme for a time-sharing computer is described in this paper. Instead of using format statements to determine the input, the computer asks the user for the required values one at a time. The computer converses with …

Numerical integration of a differential-difference equation with a decreasing time-lag

Systems in which variable time-lags are present are of common occurrence in biology. Variable flow rates are a common cause of these variable lags. At present no extensive body of knowledge exists concerning the effects which …

Use of a conditional base number system for encoding sequences of correlated characters

A procedure is described for the relatively efficient encoding of sequences of characters which have predecessor-successor selection rules. The procedure is shown to assign a unique integer to each sequence and to generate a  …

Wengert's numerical method for partial derivatives, orbit determination and quasilinearization

In a recent article in the Communications of the ACM, R. Wengert suggested a technique for machine evaluation of the partial derivatives of a function given in analytical form. In solving nonlinear boundary-value problems using …

The use of COBOL subroutines in FORTRAN main programs

If a problem requires both complicated calculations and edited output printing, then the computing part can be efficiently handled in FORTRAN and the editing part, e.g. punctuation, check protect and floating dollar sign, can …

Still another use for FORTRAN II chaining

This is to report a further use of the FORTRAN II Chain System. We, at Sandia, have modified the Chain subroutine to allow for picking up chains from the disk instead of a chain tape. The major change was the addition of a job …

On the numerical solution of an N-point boundary value problem for linear ordinary differential equations

A method for the numerical solution of the n-point boundary value problem for homogeneous linear ordinary differential equations is developed. The method requires two Runge-Kutta integrations over the interval under consideration …

Remark on Romberg quadrature

A modified form of Romberg quadrature is described, which is less sensitive to the accumulation of rounding errors than the customary one.

Expanding the editing function in language data processing

In automatic abstracting, citation indexing, mechanical translation and other such procedures, editing is required whenever the automatic method leaves something to be desired. This paper discusses the economy of editing as a …

Secondary key retrieval using an IBM 7090-1301 system

The secondary key retrieval method involves the preparation of secondary storage lists from primary data records. Search requests are satisfied by logical operations on appropriate lists, producing a complete set of addresses …

Transparent-mode control procedures for data communication, using the American standard code for information interchange—a tutorial

This paper gives the considerations of Task Group X3.3.4 in the area of transparent-mode data communication control philosophy. The appearance of this paper was forecast (under the name of “second-level control”) in the earlier …