Drawing polygons in r

The above example uses the highlightOptions parameter to emphasize the currently moused-over polygon. You can use highlightOptions with all of the shape layers described on this page. Very detailed i.

drawing polygons in r

Circles are added using addCircles. Circles are similar to circle markers ; the only difference is that circles have their radii specified in meters, while circle markers are specified in pixels. As a result, circles are scaled with the map as the user zooms in and out, while circle markers remain a constant size on the screen regardless of zoom level. When plotting circles, only the circle centers and radii are required, so the set of valid data sources is different than for polygons and the same as for markers.

See the introduction to Markers for specifics. Rectangles are added using the addRectangles function. It takes lng1lng2lat1and lat2 vector arguments that define the corners of the rectangles.

drawing polygons in r

These arguments are always required; the rectangle geometry cannot be inferred from the data object. Leaflet for R. Lines and Shapes Leaflet makes it easy to take spatial lines and shapes from R and add them to maps. Polygons are separated by rows of NA, NA. It is not possible to represent multi-polygons nor polygons with holes using this method; use SpatialPolygons instead.

geom_polygon in ggplot2

Highlighting shapes The above example uses the highlightOptions parameter to emphasize the currently moused-over polygon. Circles Circles are added using addCircles. Rectangles Rectangles are added using the addRectangles function.The default value of NULL means that no shading lines are drawn.

A zero value of density means no shading nor filling whereas negative values and NA suppress shading and so allow color filling. The default, NAis to leave polygons unfilled, unless density is specified. If density is specified with a positive value this gives the color of the shading lines.

The default, NULLmeans to use par "fg". The coordinates can be passed in a plotting structure a list with x and y componentsa two-column matrix, …. See xy. The coordinates can contain missing values. The behaviour is similar to that of linesexcept that instead of breaking a line into several lines, NA values break the polygon into several complete polygons including closing the last point to the first point.

See the examples below. When multiple polygons are produced, the values of densityanglecolborderand lty are recycled in the usual manner. Shading of polygons is only implemented for linear plots: if either axis is on log scale then shading is omitted, with a warning. These fill a region if the polygon border encircles it an odd or non-zero number of times, respectively.

Shading lines are handled internally by R according to the fillOddEven argument, but device-based solid fills depend on the graphics device.

The windowspdf and postscript devices have their own fillOddEven argument to control this. Becker, R.

How to draw POLYGON -draw any polygon by using 1 method

Created by DataCamp. Polygon Drawing polygon draws the polygons whose vertices are given in x and y. Community examples Looks like there are no examples yet.

Post a new example: Submit your example. API documentation. Put your R skills to the test Start Now.The R polygon function draws a polygon to a plot. The basic R syntax for the polygon command is illustrated above. In the following tutorial, I will show you six examples for the application of polygon in the R language.

In this example, we are going to draw a simple square polygon to an empty R plot. But as you will see in the next examples, the polygon R function has much more to offer. In the following example, I will show you how to create a frequency polygon in R.

We can draw a frequency polygon plot with the following R code. First, we draw the line of the frequency polygon with the plot function:. To make the polygon frequency plot a bit prettier, we can also add some squares at the cut-points of our frequency polygon:. And finally, we can add some line segments to the figure:. Looks good. The following application of the polygon function is quite often used to make the plot of a probability density function PDF more visible.

With the following R code, you can fill the area below a density curve with color i. Figure 4: Polygon Below Poisson Distribution. But we can modify the polygon in several ways…. As you can see, we are just overlaying the blue polygon of Example 4 with our restricted polygon. However, we could of cause just skip the polygon of Example 4 and draw only the restricted polygon.

At this point, you know how to restrict polygons to certain X-values. However, we could also restrict a polygon to certain values on the Y-axis…. We can either restrict our density polygon to a fixed Y-range — or even prettier, we can restrict our polygon to the shapes of two densities.

We can now use the values of our first and second density to draw a polygon between the two densities:. As you can see in the plot, the second densities follows a normal distribution that is partly lower and partly higher than our first density. Interestingly, the polygon is reflecting this by drawing the polygon sometimes below the first density line and sometimes above the first density line.

You need even more examples? No problem! Just have a look at the following video of the YouTube channel intromediateecon. In the video, the speaker explains some cool tricks for the application of polygon in R — especially for drawing polygon shades below a bell curve. Your email address will not be published. Post Comment.In the previous part, we presented general concepts with a map with little information country borders only. The modular approach of ggplot2 allows to successively add additional layers, for instance study sites or administrative delineations, as will be illustrated in this part.

The full list of packages necessary for this series of tutorials can be installed with:. We start by loading the basic packages necessary for all maps, i. The package rnaturalearth provides a map of countries of the entire world.

The function can return sp classes default or directly sf classes, as defined in the argument returnclass :. We start by defining two study sites, according to their longitude and latitude, stored in a regular data.

Drawing beautiful maps programmatically with R, sf and ggplot2 — Part 2: Layers

As such, we can adjust all characteristics of points e. A better, more flexible alternative is to use the power of sf : Converting the data frame to a sf object allows to rely on sf to handle on the fly the coordinate system both projection and extentwhich can be very useful if the two objects here world map, and sites are not in the same projection. To achieve the same result, the projection here WGS84, which is the CRS code has to be a priori defined in the sf object:.

It would be informative to add finer administrative information on top of the previous map, starting with state borders and names. The package maps which is automatically installed and loaded with ggplot2 provides maps of the USA, with state and county borders, that can be retrieved and converted as sf objects:. State names are part of this data, as the ID variable.

A simple but not necessarily optimal way to add state name is to compute the centroid of each state polygon as the coordinates where to draw their names. WGS84 are not exact, which is perfectly fine for our drawing purposes. State names, which are not capitalized in the data from mapscan be changed to title case using the function toTitleCase from the package tools :. County data are also available from the package mapsand can be retrieved with the same approach as for state data.

We can also fill in the county using their area to visually identify the largest counties. To make a more complete map of Florida, main cities will be added to the map. We first prepare a data frame with the five largest cities in the state of Florida, and their geographic coordinates:. Once you have your API key, you can run the following code to automatically retrieve geographic coordinates of the five cities:. We can now convert the data frame with coordinates to sf format:.

This is not really satisfactory, as the names overlap on the points, and they are not easy to read on the grey background. For the final map, we put everything together, having a general background map based on the world map, with state and county delineations, state labels, main city names and locations, as well as a theme adjusted with titles, subtitles, axis labels, and a scale bar:.

This example fully demonstrates that adding layers on ggplot2 is relatively straightforward, as long as the data is properly stored in an sf object. The full list of packages necessary for this series of tutorials can be installed with: install.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service. The dark mode beta is finally here.

Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. Note that you need to install the pillow library.

Also, I scaled up your coordinates by the factor of so that we can see the polygon on the x screen. First needs tkintersecond - pygame. So if your polygon is flying and bouncing around, use second, but if it's just stable thing, use first.

Also, in python2 use from Tkinternot from tkinter. I've checked this code on raspberrypi3, it works. PIL in this case uses imagemagickwhich is really good image editing tool. All the other answers seems veryhigh level, I guess that is my impression as a mechanical engineer. Here's a simple version of the code:. If you want to draw polygons on a matrix representing an image, scikit-image has 3 functions for you:.

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Correct me if your benchmark said the contrary, but I think these functions are quite fast. Learn more. How to draw polygons with Python?

drawing polygons in r

Ask Question. Asked 2 years, 11 months ago. Active 2 months ago. Viewed 24k times. I have input values of x, y coordinates in the following format: [[1,1], [2,1], [2,2], [1,2], [0. Raptor Fan W. Fan 1 1 gold badge 1 1 silver badge 3 3 bronze badges. Which library are you using for drawing? Active Oldest Votes. Using matplotlib. Julien Julien 8, 3 3 gold badges 20 20 silver badges 43 43 bronze badges.

Maybe you add plt. I use Spyder and plt. Another way to draw a polygon is this: import PIL. Hope this helps. Nurjan Nurjan 4, 4 4 gold badges 26 26 silver badges 42 42 bronze badges. PIL in this case uses imagemagickwhich is really good image editing tool If you also need to apply effects on image, use PIL. If you need more difficult math-figures, use matplotlib.

For animation, use pygame.Raw on GitHub. Edit this page. For a long time, R has had a relatively simple mechanism, via the maps package, for making simple outlines of maps and plotting lat-long points and paths on them. More recently, with the advent of packages like sprgdaland rgeosR has been acquiring much of the functionality of traditional GIS packages like ArcGIS, etc.

This is an exciting development, but not always easily accessible for the beginner, as it requires installation of specialized external libraries that may, on some platforms, not be straightforward and considerable familiarity with GIS concepts. More recently, a third approach to convenient mapping, using ggmap has been developed that allows the tiling of detailed base maps from Google Earth or Open Street Maps, upon which spatial data may be plotted.

Nor will cover the somewhat more simplified approach to projections using the mapproj package. It is pretty sweet, but does not support different projections. I feel that the above twp topics should cover a large part of what people will need for making useful maps of field sites, or sampling locations, or fishing track lines, etc.

Here is no fill, with a red line. Remember, fixed value of aesthetics go outside the aes function. This is just like it is above, but we can map fill to region and make sure the the lines of state borders are white. We now have the numbers that we want, but we need to attach those to every point on polygons of the counties.

If you were needing a little more elbow room in the great Golden State, this shows you where you can find it:. I personally like more color than ggplot uses in its default gradient. Can we do something similar with ggplot? Note that the scale of these maps from package maps are not great.

We can zoom in to the Bay region, and it sort of works scale-wise, but if we wanted to zoom in more, it would be tough. The ggmap package is the most exciting R mapping tool in a long time! You might be able to get better looking maps at some resolutions by using shapefiles and rasters from naturalearthdata. That was a fail, but we got a warning about it too. Zoom levels go from 3 world scale to 20 house scale.

For this, I have whittled down some stuff in the coded wire tag data base to georeferenced marine locations in British Columbia where at least one Chinook salmon was recovered in between and inclusive.

To see how I did all that you can check out this. These locations in BC are hierarchically structured. That looks good. It appears like we could probably color code over the whole area down to region, and then down to area within subregions. Note that I am saving them to PDFs because it is no fun to make a web page with all of those in there.

Authored by Eric C. Anderson working as a Federal employee. Content on this website is a government work in the public domain in the U. Templates and plugins to build the site are modified from Hadley Wickham's Advanced R website. Powered by jekyllknitrand pandoc.

Source available on github. Reproducible Research Course by Eric C. How's this site built? See all sources at the course repository on GitHub. Making Maps with R Intro For a long time, R has had a relatively simple mechanism, via the maps package, for making simple outlines of maps and plotting lat-long points and paths on them.

Use ggmap to make some pretty decent looking maps I feel that the above twp topics should cover a large part of what people will need for making useful maps of field sites, or sampling locations, or fishing track lines, etc.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service.

The dark mode beta is finally here. Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. I would like to draw SpatialPolygons from library sp with holes in ggplot2. In ggplot2, the way polygons with holes are drawn force to draw them once using filland another time using colourotherwise you may see lines crossing polygons.

When dealing with multiple subpolygons, some with holes, this is more tricky, the order of points features as defined by broom::tidy may not allow for filling polygons see image below. Do any of you have a solution to get rid of this filling problem behaviour? Could be a good time to "go over" to the sf package. Adding lines shows the source of the problem. This code which is not very elegant, sorry makes the path go back to the starting point of the first piece before proceeding to 3rd.

This post is a good question and already received great answers. I also believe people should learn how to work with sf objects as it is the next generation of the spatial data type in R. Learn more. Draw SpatialPolygons with multiple subpolygons and holes using ggplot2 Ask Question.

Asked 2 years, 10 months ago. Active 6 months ago. Viewed times. Glorfindel One solution would involve separating the polygons in the SpatialPolygons function call.

Is this a possibility or are you looking for a solution from xy. Active Oldest Votes. Yes indeed. Your answer solves the problem asked here in a simple way. I guess this will encourage people having this problem to migrate to sf I was personally waiting the moment when sf was stable enough with parameters and function names. However, this raises my other problem of being able to draw hatched area polygons with sf features.


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