Spatial | GIS and Spatial Analysis lecture notes | Map library
kandi X-RAY | Spatial Summary
kandi X-RAY | Spatial Summary
these pages are a compilation of lecture notes for my introduction to gis and spatial analysis course (es214). they are ordered in such a way to follow the course outline, but most pages can be read in any desirable order. the course (and this book) is split into two parts: data manipulation & visualization and exploratory spatial data analysis. the first part of this book is usually conducted using arcgis desktop whereas the latter part of the book is conducted in r. arcgis was chosen as the gis data manipulation environment because of its “desirability” in job applications for undergraduates in the unites states. but other gis software environments, such as the open source software qgis, could easily be adopted in lieu of arcgis–even r can be used to perform many spatial data manipulations such as clipping, buffering and projecting. even though some of the chapters of this book make direct reference to
Support
Quality
Security
License
Reuse
Top functions reviewed by kandi - BETA
Currently covering the most popular Java, JavaScript and Python libraries. See a Sample of Spatial
Spatial Key Features
Spatial Examples and Code Snippets
Lines of Code : 57License : Non-SPDX (Apache License 2.0)
Copydef _with_space_to_batch_adjust(orig, fill_value, spatial_dims):
"""Returns an `adjusted` version of `orig` based on `spatial_dims`.
Tensor of the same type as `orig` and with shape
`[max(spatial_dims), ...]` where:
adjusted[spatial_dims[ static void withSpatialPartition(
int height, int width, int numOfMovements, HashMap bubbles) {
//creating quadtree
var rect = new Rect(width / 2D, height / 2D, width, height);
var quadTree = new QuadTree(rect, 4);
//will run n def _spatial_output_shape(self, spatial_input_shape):
return [
conv_utils.conv_output_length(
length,
self.kernel_size[i],
padding=self.padding,
stride=self.strides[i],
dilation= Community Discussions
Trending Discussions on Spatial
QUESTION
I am working on a spatial search case for spheres in which I want to find connected spheres. For this aim, I searched around each sphere for spheres that centers are in a (maximum sphere diameter) distance from the searching sphere’s center. At first, I tried to use scipy related methods to do so, but scipy method takes longer times comparing to equivalent numpy method. For scipy, I have determined the number of K-nearest spheres firstly and then find them by cKDTree.query, which lead to more time consumption. However, it is slower than numpy method even by omitting the first step with a constant value (it is not good to omit the first step in this case). It is contrary to my expectations about scipy spatial searching speed. So, I tried to use some list-loops instead some numpy lines for speeding up using numba prange. Numba run the code a little faster, but I believe that this code can be optimized for better performances, perhaps by vectorization, using other alternative numpy modules or using numba in another way. I have used iteration on all spheres due to prevent probable memory leaks and …, where number of spheres are high.
ANSWER
Answered 2022-Feb-14 at 10:23Have you tried FLANN?
This code doesn't solve your problem completely. It simply finds the nearest 50 neighbors to each point in your 500000 point dataset:
QUESTION
I have been using "sae" package for R to use small area estimations with spatial fay-herriot models (SFH). Using different distance matrices I occasionally obtained negative values of Mean Squared Errors (MSE).
The following link may reference a similar behavior:
scikit-learn cross validation, negative values with mean squared error
In any case here is a working example:
...ANSWER
Answered 2022-Feb-25 at 14:28I'm pretty sure that this is due to bias correction that generally takes place when you have MSE. You can read about the formula for bias correction that is used in the references they provided in ?sae::meanSFH. In one of the articles, they provided a case study where the average MSE is negative. (I found this in Molina et al., 2009. They identify the bias correction in a few places, but it's very clear on pp. 452-453.)
You can visualize the errors and see how very close they are to zero.
QUESTION
I am working on submitting an R package to CRAN. Right now I am trying to reduce the memory footprint of the package. Because this package deals with spatial data that has a very particular format, I want to include a properly formatted shapefile as an example. If I include the full-size original shapefile, there are no warnings (other than file size) in the R CMD checks. However, if I crop the file and include the cropped version in the package (in "inst/extdata") I get this warning:
...ANSWER
Answered 2022-Feb-11 at 23:59This is a known issue[1] where file will mis-identify DBF files with last-update date in the year 2022. Easiest fix is to not use a 2022 update date when saving the file. Alternatively you can simply change the second byte of the file after the fact, e.g.:
QUESTION
I hope this is a simple question but I currently can't wrap my head around.
What I want to do is break out of a while loop which contains a delay when a promise gets resolved.
In pseudocode this would look like:
...ANSWER
Answered 2022-Feb-01 at 19:45Minor modification of your idea to make it work better:
QUESTION
I am maintaining an R package for spatial data. When I run checks on R-devel (Windows), I get: "Warning: multiple methods tables found for 'direction'", which prohibits me from resubmitting my R package. I've checked and there is only one function direction() which is from the raster package - a package I don't explicitly import, but is suggested in sf which I do. Any ideas of what this could be/a workaround?
ANSWER
Answered 2022-Jan-14 at 21:35> library(sp)
> library(raster)
Warning messages:
1: multiple methods tables found for 'direction'
2: multiple methods tables found for 'gridDistance'
QUESTION
I am trying to find the end-effector spatial velocity Jacobian for a robot with a free-floating base. Due to the free-floating base, the jacobian should contain a base component and a manipulator comment (see https://spart.readthedocs.io/en/latest/Tutorial_Kinematics.html#jacobians)
V_ee = end-effector spatial velocity
J_b = base jacobian component
J_m = manipulator jacobian component
v = generalized velocities
V_ee = [J_b, J_m] v
Until now, I was using SPART toolbox to do this in Matlab (https://github.com/NPS-SRL/SPART) and now I am moving to Drake. I tried using CalcJacobianSpatialVelocity in the MultiBodyPlant and the manipulator Jacobian is correct when compared to SPART. However, the base component of the Jacobian is all zeros. This is different from what I expected and from SPART as for a free-floating base, the base velocities contribute to the end-effector spatial velocities.
An example reproduction of this issue can be found here: https://colab.research.google.com/github/vyas-shubham/DrakeTests/blob/main/freeFloating/computeJacobian.ipynb
I think I'm either doing one of these wrong while using Drake:
- Using the CalcJacobianSpatialVelocity wrong. This is unlikely as the manipulator jacobian is correct and the base frame is also correct (only 1 frame in URDF).
- Making a wrong URDF for calculating Jacobians for Free-Floating base. Maybe I need to specify differently in URDF a floating-base for Drake to include this in the Jacobian computation?
ANSWER
Answered 2022-Jan-03 at 23:01Your code is taking the Jacobian of the chaser relative to the target; there is no floating base between them (so the jacobian wrt to the floating base should, indeed, be zero). I think, perhaps, that you want to make frame_A=world_frame?
QUESTION
I have a graph where each node has a spatial position given by (x,y), and the edges between the nodes are only connected if the euclidean distance between each node is sqrt(2) or less. Here's my example:
...ANSWER
Answered 2021-Dec-31 at 10:08I tried applying a Genetic Algorithm to the problem above. I made an initial guess that two additional nodes would connect all three disconnected components.
QUESTION
I am looking for a way to detect if the device I am using can support Dolby Atmos sounds.
After searching around I found this call.
https://github.com/w3c/media-capabilities/blob/main/explainer.md#spatial-audio
...ANSWER
Answered 2021-Dec-24 at 06:57Detecting the codec doesn't necessarily detect whether the system can support Dolby Atmos
Correct.
What reliable way is there to detect if your system will truly support Dolby Atmos whether its with a receiver or a Dolby Atmos compliant sound bar.
Unfortunately, this undetectable from the browser.
The browser itself and even the OS doesn't always know what is downstream. Sorry for the bad news!
QUESTION
I have a set of data values for a scalar 3D function, arranged as inputs x,y,z in an array of shape (n,3) and the function values f(x,y,z) in an array of shape (n,).
EDIT: For instance, consider the following simple function
...ANSWER
Answered 2021-Nov-16 at 17:10All you need is just reshape F[:, 3] (only f(x, y, z)) into a grid. Hard to be more precise without sample data:
If the data is not sorted, you need to sort it:
QUESTION
I would like to extract the unit of measurement (decimal degrees, metres, feet, etc.) from a spatial object in R. For example, if I have an SF data frame that uses the WGS84 co-ordinate reference system (EPSG:4326), I would like to be able to determine that the co-ordinates are specified in decimal degrees. Similarly, I'd like to be able to determine that UTM co-ordinates (e.g. EPSG:32615) are specified in metres.
I have tried using the st_crs() function from the sf package, which returns the co-ordinate reference system in well-known text format. However, I'm struggling to be certain that a regex that extracts the unit of measurement from that well-known text will operate reliably for a wide range of co-ordinate systems.
Is there an existing function that returns the measurement unit for a spatial object?
For example, the following code produces an SF data frame that uses the WGS84 co-ordinate system:
...ANSWER
Answered 2021-Dec-21 at 15:05st_crs() has a parameters argument that returns a list of useful CRS parameters when TRUE, including the units of the CRS. Here's an example with the built-in nc data:
Community Discussions, Code Snippets contain sources that include Stack Exchange Network
Vulnerabilities
No vulnerabilities reported
Install Spatial
Support
Reuse Trending Solutions
Find, review, and download reusable Libraries, Code Snippets, Cloud APIs from over 650 million Knowledge Items
Find more librariesStay Updated
Subscribe to our newsletter for trending solutions and developer bootcamps
Share this Page
