maps

SuperMap Desktop中配置Google Maps地图投影

由 会有一股神秘感。 提交于 2020-01-24 00:22:09
我们先来了解一下Google Maps采用的地图投影 Google Maps 、 Virtual Earth 等网络地理所使用的地图投影，常被称作 Web Mercator 或 Spherical Mercator ，它与常规墨卡托投影的主要区别就是把 地球模拟为球体而非椭球体 。为什么要投影，请参见LionGG的 《 地图投影为什么 》 为什么是圆形球体，而非椭球体？ 这说来简单，仅仅是由于实现的方便，和计算上的简单，精度理论上差别0.33%之内，特别是比例尺越大，地物更详细的时候，差别基本可以忽略。 Google Maps使用的是WGS 84的参考球体 。 Web 墨卡托投影坐标系 ： 以整个世界范围，赤道作为标准纬线，本初子午线作为中央经线，两者交点为坐标原点，向东向北为正，向西向南为负。 X轴：由于赤道半径为6378137米，则赤道周长为2*PI*r = 2*20037508.3427892，因此X轴的取值范围： [-20037508.3427892,20037508.3427892]。 Y轴：由墨卡托投影的公式可知，同时上图也有示意，当纬度φ接近两极，即90°时，y值趋向于无穷。这是那些“懒惰的工程师”就把Y轴的取值范围也限定在 [-20037508.3427892,20037508.3427892]之间，搞个正方形。 懒人的好处，众所周知，事先切好静态图片

Google Api Key Missing

由 纵然是瞬间 提交于 2020-01-23 11:52:49
问题 I am trying to launch an android wearable with an emulator, but it crashes on startup and getting the following error: java.lang.RuntimeException: API key not found. Check that <meta-data android:name="com.google.android.geo.API_KEY" android:value="your API key"/> is in the <application> element of AndroidManifest.xml But the weird part is i did defined it in my manifest like this: New editted that "works" <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com

Google Api Key Missing

由 家住魔仙堡 提交于 2020-01-23 11:52:31
问题 I am trying to launch an android wearable with an emulator, but it crashes on startup and getting the following error: java.lang.RuntimeException: API key not found. Check that <meta-data android:name="com.google.android.geo.API_KEY" android:value="your API key"/> is in the <application> element of AndroidManifest.xml But the weird part is i did defined it in my manifest like this: New editted that "works" <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com

GMap .net offline

由 帅比萌擦擦* 提交于 2020-01-22 20:15:08
问题 I'm developing an application using Gmap in c# (great API, btw), not to confuse with google-map API, and I did some really cool and useful stuff ever since. My problem is that some of my clients won't have an internet connection, and that is why I need to be able to display the background (the map) offline. I used to use the property GMap.NET.AccessMode.ServerAndCache; to get my data from the server, and now I would like to be able to use GMap.NET.AccessMode.CacheOnly with a full cache.

Calculate distance and ETA from maps in swift

由 百般思念 提交于 2020-01-22 15:57:47
问题 I am currently using this code below that will open maps with driving guide to a certain destination. let lat1 : NSString = "57.619302" let lng1 : NSString = "11.954928" let latitute:CLLocationDegrees = lat1.doubleValue let longitute:CLLocationDegrees = lng1.doubleValue let regionDistance:CLLocationDistance = 10000 let coordinates = CLLocationCoordinate2DMake(latitute, longitute) let regionSpan = MKCoordinateRegionMakeWithDistance(coordinates, regionDistance, regionDistance) let options = [

Remove border lines in ggplot map/choropleth

由 心不动则不痛 提交于 2020-01-22 10:53:50
问题 I would like to remove the lines between regions of a choropleth generated in ggplot . My question is motivated by a very large map with very very small regions (census block groups) that are so numerous that it's impossible to see the color filling the shape given the density of the borders. I'm using updated RStudio on a Mac with ggplot2 version 1.0.0; the same problem does not seem to occur on Windows. Here are examples (using counties) that have different colors for each county so that

Remove border lines in ggplot map/choropleth

由 牧云@^-^@ 提交于 2020-01-22 10:52:05
问题 I would like to remove the lines between regions of a choropleth generated in ggplot . My question is motivated by a very large map with very very small regions (census block groups) that are so numerous that it's impossible to see the color filling the shape given the density of the borders. I'm using updated RStudio on a Mac with ggplot2 version 1.0.0; the same problem does not seem to occur on Windows. Here are examples (using counties) that have different colors for each county so that

Class not found when unmarshalling: android.support.v7.widget.Toolbar$SavedState

由 点点圈 提交于 2020-01-21 01:45:25
问题 i am using Maps API to create a simple android app and i get a wierd error i can't solve. It usually happens when i rotate my device. I'm using google services 8.4.0 4-23 15:39:47.503 9419-9419/com.licenta.vladut.mmap E/Parcel: Class not found when unmarshalling: android.support.v7.widget.Toolbar$SavedState java.lang.ClassNotFoundException: android.support.v7.widget.Toolbar$SavedState at java.lang.Class.classForName(Native Method) at java.lang.Class.forName(Class.java:308) at android.os

Django and Folium integration

由 最后都变了- 提交于 2020-01-20 08:20:29
问题 Django newbie here: my aim is to integrate Folium to an html page. so what I have at the moment: polls/views.py def show_map(request): #creation of map comes here + business logic m = folium.Map([51.5, -0.25], zoom_start=10) test = folium.Html('<b>Hello world</b>', script=True) popup = folium.Popup(test, max_width=2650) folium.RegularPolygonMarker(location=[51.5, -0.25], popup=popup).add_to(m) context = {'my_map': m} return render(request, 'polls/show_folium_map.html', context) polls/urls.py

Converting code using hash to array

由 人走茶凉 提交于 2020-01-17 15:31:21
问题 I am charged with making a Perl module more efficient. It takes log entries which are currently uniquely identified by date and server name and inserts them into our mysql database for later processing. I've posted the original file and my attempt below. My code doesn't insert into the database. I'm sure its a simple array handling problem but not sure. Original file package UlsaSpectrumAnalyser; use strict; use warnings; use Data::Dumper; use EnmServiceGroup; use StatsDB; use DBI; use
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