Contribution to the high precision local networks general problem: Specific theoretician and practical conditions of judgement, intermediate parameters qualifications and final results (Spanish text).

摘要

The present investigation deals with the reliability of the data, intermediate parameters and final results concerning the design, observation and computation of a local high precision network.; Nowadays precision, rigour, quality definitively is highly demanded.; Precision concept is fundamental in any geodetic work and, joined with reliability and cost, define the three fundamental parameters in any geodetic action (Nunez et al. 1991).; It can be defined reliability as the capacity of a network to detect gross errors in the observations. (Nunez et al. 1991).; So it is necessary to check the error figures and computation algorithms, included the numerical rounding errors introduced by the successive arithmetic operations of the computer, which play an important role.; An important part of the investigation is devoted to the resolution of a least-squares equations system as an example Ax-K=R (where A is the design matrix, K the independent terms vector and R the residuals vector), both free network or tie, where it can be found that the matrix S=ATPA is highly sensitive to any rounding operation, resulting in a great discrepancies in the solution vector of the unknowns X.; This sensibility is inevitable and could become a grave inconvenient in the final results of a network with highly levels of precision and rigour demanded, such as deforming networks.; However, before to decide the observation repetition, probably with a new methodology and another instrumentation, we can improve the situation with some new calculation procedure.; Main topics of the investigation are: (1) Error boundaries in S and b=ATPK. (2) Matrix inverse alternatives. (3) Consideration about all the information available in the covariance matrix through a new error figures. (4) Error figures about observables. (5) Lineal system equations generation with exact design matrices which avoid the rounding errors.; These are the principal aspects to be treated in the present investigation entitled: "Contribution to the high precision local networks general problem: specific theoretician and practical conditions of judgement, intermediate parameters qualifications and final results".