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Fri Apr 29 06:00:01 EDT 2022 ======================================== Slept from ten to six-thirty. Woke briefly around four. Mostly sunny until late afternoon then becoming partly cloudy. Highs in the upper 50s. Southeast winds 5 to 10 mph. Fifteen minutes on the exercise bike in the morning. # Work Geospatial community sessions, played with QGIS a little. https://docs.qgis.org/3.22/en/docs/gentle_gis_introduction/index.html 3.10. Common problems with vector data > Working with vector data does have some problems. We already mentioned the issues that can arise with vectors captured at different scales. Vector data also needs a lot of work and maintenance to ensure that it is accurate and reliable. Inaccurate vector data can occur when the instruments used to capture the data are not properly set up, when the people capturing the data aren’t being careful, when time or money don’t allow for enough detail in the collection process, and so on. > > If you have poor quality vector data, you can often detect this when viewing the data in a GIS. For example slivers can occur when the edges of two polygon areas don’t meet properly (see Fig. 3.39). > ../../_images/vector_slivers.png > > Fig. 3.39 Slivers occur when the vertices of two polygons do not match up on their borders. At a small scale (e.g. 1 on left) you may not be able to see these errors. At a large scale they are visible as thin strips between two polygons (2 on right). > > Overshoots can occur when a line feature such as a road does not meet another road exactly at an intersection. Undershoots can occur when a line feature (e.g. a river) does not exactly meet another feature to which it should be connected. Figure Fig. 3.40 demonstrates what undershoots and overshoots look like. > ../../_images/vector_overshoots.png > > Fig. 3.40 Undershoots (1) occur when digitised vector lines that should connect to each other don’t quite touch. Overshoots (2) happen if a line ends beyond the line it should connect to. We did a s'mores team-building thing at work that was kind of fun. Madlibs and campire stories over video conference. # Home * [x] drop off guitar at Kate's * [ ] D&D tonight? No, but maybe Mothership with Ed and Jay? Dropped off a guitar and amp for Isla after work. Chatted with Kate for a few minutes. Ten minute walk in the evening. Sunny and not cold. Saw several morning doves, and heard a woodpecker pecking. Chatted with Ed on Jitsi for a few minutes. Servings: grains 5/6, fruit 1/4, vegetables 2/4, dairy 2/2, meat 2/3, nuts 1/0.5 Breakfast: pineapple, coffee, naan, egg, beans, tomatoes Lunch: Cappuccino, beef burrito Dinner: chips, salsa

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