Vue error resolution: typeerror: cannot read property ‘_ t’ of undefined”

[Vue warn]: Error in render: “TypeError: Cannot read property ‘_t’ of undefined”
The compatibility issue between Vue and i18n is the multi-language configuration used in the project. The solution is as follows:

    Vue.use(iView)

replace

Vue.use(iView, {
  i18n: function(path, options) {
    let value = i18n.t(path, options)
    if (value !== null && value !== undefined) {
      return value
    }
    return ''
  }
})

Internationalization other items are configured unchanged and are recorded only.
Reference articles:
https://github.com/iview/iview/issues/1090

How does lightningchart, a high performance chart control, draw maps in 3D?

LightningChart is primarily a charting component (charts are graphical representations of data) rather than a virtual environment creation tool. However, LightningChart provides multiple ways to use geographic maps, not only in 2D, but also in 3D.
If you are primarily interested in 3D maps, Artion can provide three examples of possible ideas. First, you can import a map/image into a “chart” and create a surface whose geometry and color are based on map elements (such as shading). Example of this type in ExampleArgesurface:

Example large surface
As shown in ExampleGlobal Surface3D, such a surface can be wrapped in any shape

Example Globesurface3D
You can also use the information/data from the map (for example, boundary residents, population size, etc.) to create Chart 3D objects (which can be pointlineseries3D, meshModel, polygon3D, etc.). In ExamplePopulationPolygons3D demonstrates a kind of such a method.

Example population polygon 3D
LightningChart.net is fully GPU-accelerated and optimized for displaying massive amounts of data in real time — over 1 billion data points. LightningChart includes a wide range of 2D, Advanced 3D, Polar, Smith, 3D Pake/Doughnut, Geographic Maps and GIS charts as well as volume mapping capabilities for science, engineering, medicine, aviation, trade, energy and other fields.

Solution to the problem of selecting node sass when creating vue-cli3

Because :
vue-cli3.0 defaults to using the yarn package management tool instead of the original NPM

In yarn, node-sass, the default download will most likely fail if you don’t over the wall

The solution

	yarn config set sass_binary_site http://cdn.npm.taobao.org/dist/node-sass -g

So when use the yarn to download the node – sass don’t stuck an error failed to install
this method not only solve the vue cli3 installation node – sass error
is used to solve the yarn package management tools installation node – sass error problem
Problem solving

Leetcode 832. Flip image

Answer key
They’re very clear, so do what they say, flip it horizontally first, and then flip it backwards.
Horizontal reverse can use its own reverse, reverse directly and 1 XOR can be.
code

class Solution {
public:
    vector<vector<int>> flipAndInvertImage(vector<vector<int>>& A) {
        int n = A.size();
        for(int i = 0; i < n; i++){
            reverse(A[i].begin(),A[i].end());
        }
        for(int i = 0; i < n; i++){
            for(int j = 0; j < A[0].size(); j++){
                A[i][j] = A[i][j]^1;
            }
        }
        return A;
    }
};

Fatal: reusing to merge unrelated histories

Git: fatal: refusing to merge unrelated nothing is solved
Today to create a local warehouse (README), the local warehouse and making the association, found that the git pull, git feach remind fatal: refusing to merge unrelated nothing

access to the Internet to check the reason was that the two branches are two different versions, and have different submission history

add

$git pull origin master --allow-unrelated-histories

Can allow irrelevant history to mention, forced merger, really solved this problem, thank you

Resolving fatal: reusing to merge unrelated histories in Git

An error of Git
Sometimes there are some problems in the process of using Git, so when you solve each problem, you need to summarize and record it, so that you won’t do it again.
A, fatal: refusing to merge unrelated nothing
Today, while creating a project with Git, the following error occurred when two branches were merged.

~/SpringSpace/newframe on  master ⌚ 11:35:56
$ git merge origin/druid
fatal: refusing to merge unrelated histories

The key to the problem here is: fatal: refusing to merge unrelated nothing
you might be in the git pull or git push are likely to encounter, this is because the two branches without relationship. So what's the solution?
Second, solutions
Behind the commands you add - allow - unrelated - nothing
for example:
git merge master - allow - unrelated - nothing 

~/SpringSpace/newframe on  druid ⌚ 11:36:49
$ git merge master --allow-unrelated-histories
Auto-merging .gitignore
CONFLICT (add/add): Merge conflict in .gitignore
Automatic merge failed; fix conflicts and then commit the result.

If you are a git pull or git push to fatal: refusing to merge unrelated nothing
in the same way:
git pull origin master - allow - unrelated - nothing
and so on, this is the perfect solution to cough up!

fatal: refusing to merge unrelated histories

Git: fatal: refusing to merge unrelated nothing to solve the
today creates a local warehouse (README), the local warehouse, and making the association, found that the Git pull, Git feach remind fatal: refusing to merge unrelated nothing
the reason was that the two branches are two different versions, with a different history

git pull origin master --allow-unrelated-histories

window.open () several ways to open windows

    opens Baidu in the current window and makes the URL appear in the search bar.
window.open("http://www.baidu.com/", "_self");
    Open Baidu
a new window

window.open("http://www.baidu.com/", "_blank");
    Open a new window and name it “hello”
window.open("", "hello");
    > In addition, there are several options for the second argument of the open function :
_top: If there are framesets on the page, the URL replaces the top layer of framesets. That is, if there are no framesets, the effect is equivalent to _self._parent: the page pointed to by the URL is loaded into the parent of the current frame. If there are no framesets, the effect is equivalent to _self._media: the page pointed to by the URL is loaded into the HTML code area contained in the Media Bar. If there is no Media Bar, add it to itself.

    If you want to add something else to the new window, you need a third parameter :
Channelmode: yes | no | 1 | 0 (window display for theater mode [full screen displays the current web page, including the toolbar], or channel mode [general show]). Directories: yes | no | 1 | 0 (whether to add directory buttons, such as under the IE there could be a “link” button on the top) fullscreen: yes | no | 1 | 0 (the browser handle full screen mode, and hide the title bar and menu, etc.) the menubar: Yes | no | 1 | 0 (whether to display the menu bar of the browser by default) resizeable: yes | no | 1 | 0 (window can resize) scrollbars: yes | no | 1 | 0) (whether to allow a horizontal or vertical scroll bar titlebar: yes | no | 1 | 0 (whether to add a title bar) toolbar: yes | no | 1 | 0 (whether to add the default browser toolbar) status: Yes | no | 1 | 0 (whether to display the status bar) location: yes | no | 1 | 0 (whether to display the search bar) copyhistory: yes | no | 1 | 0 (seems to have been abandoned, if as long as the toolbars, according to the history button will be displayed) height: the height of the window, the minimum value of 100 pixels width: the width of the window, the minimum value of 100 pixels left: the window of the distance relative to the screen on the left

window.open("http://www.baidu.com/", "_self","height=400,width=400,top=10,left=10,resizable=yes");

There is one last argument to the open function, which is about history, whether the window being opened has the same history URL as the window being opened, or whether it is a separate memory.