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Reading vector data files to in‐memory data models efficiently is a crucial step to handle the ever‐growing volume of geographical data. Although advanced IO solutions like distributed file systems or Message Passing Interface parallel IO work well in some high‐end computing environments, the 20‐year‐old OGR simple features library is still the de facto tool for loading vector files when developing GIS algorithms in most scenarios, which is not very efficient when data become larger. In this article, we analyze the bottleneck of the OGR library and find that excessive small objects are the main source of slowness. We then offer advice to improve efficiency when using OGR. To further verify our findings and provide an alternative to the OGR library in performance‐sensitive scenarios, we develop a library based on continuous memory pools to avoid small objects. Experiments show that our advice is effective and our library can be several times faster than the OGR library for IO‐intensive programs. [ABSTRACT FROM AUTHOR]

The first application of GaoFen-3 synthetic aperture radar (SAR) interferometry to monitoring co-seismic deformation of an earthquake is presented in this paper. First, two GaoFen-3 SAR images spanning the 2017 surface-wave magnitude ( M s ) 7.0 Jiuzhaigou earthquake were mosaicked, coregistered and processed into an interferogram with visible fringes. After the removal of severe orbital errors and unwrapping, the co-seismic deformation field is obtained. Finally, the fault parameters and slip distribution are determined based on the deformation field. To evaluate the performance of GaoFen-3 in this case, the interferogram, co-seismic deformation field, derived fault parameters and slip distribution are compared with those derived from Radarsat-2, Sentinel-1A and Advanced Land Observing Satellite-2 (ALOS-2) Phased Array type L-band Synthetic Aperture Radar-2 (PALSAR-2). The comparisons between the deformation field obtained from GaoFen-3 and those obtained from Radarsat-2 and Sentinel-1A show Pearson's correlation coefficient ( r) values > 90%, demonstrating that GaoFen-3 interferometry can measure the co-seismic deformation effectively. The resultant slip model obtained by GaoFen-3 interferometric measurements shows a simple, elliptical pattern of slip, reaching a maximum of approximately 1 m at depths of 10–13 km. The rake angle is almost 0 ∘ , which suggests left-lateral strike-slip motion, consistent with previous studies. [ABSTRACT FROM AUTHOR]