小编Kai*_*tze的帖子

import pandas as pd
import pandas_datareader.data as web

coins = pd.read_html('https://coinmarketcap.com/')

for name in coins[0][1][1:]:
    print(name)

结果在下面的错误消息中.当我打印硬币时,我得到了完整的表格,但是当我尝试获取特定信息时,它会给我这个错误消息.我知道这种格式是有效的,因为我已经从我学习的其他练习中完全复制了它,并且刚刚更改了网站.非常感谢.

C:\Users\AppData\Local\Programs\Python\Python36-32\python.exe C:/Users/Desktop/python_work/crypto/crypto_corr.py
Traceback (most recent call last):
  File "C:\Users\AppData\Local\Programs\Python\Python36-32\lib\site-packages\pandas\core\indexes\base.py", line 2525, in get_loc
    return self._engine.get_loc(key)
  File "pandas\_libs\index.pyx", line 117, in pandas._libs.index.IndexEngine.get_loc
  File "pandas\_libs\index.pyx", line 139, in pandas._libs.index.IndexEngine.get_loc
  File "pandas\_libs\hashtable_class_helper.pxi", line 1265, in pandas._libs.hashtable.PyObjectHashTable.get_item
  File "pandas\_libs\hashtable_class_helper.pxi", line 1273, in pandas._libs.hashtable.PyObjectHashTable.get_item
KeyError: 1

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:/Users/Desktop/python_work/crypto/crypto_corr.py", line 6, in <module>
    for name …

当我在 Travis-CI 上测试 Angular 项目时，出现了两个异常：

$ ng test
The test command requires to be run in an Angular project, but a project definition could not be found.
The command "ng test" exited with 1.

$ ng e2e
The e2e command requires to be run in an Angular project, but a project definition could not be found.
The command "ng e2e" exited with 1.

错误消息非常令人困惑。我用谷歌搜索了“ Angular 项目定义”，但没有找到任何相关内容。

我查看了Angular CLI wiki，但没有关于ng test和 的有用信息ng e2e，更不用说“项目定义 …

在阅读了Git - git-submodule 文档后，我决定将以前项目中的两个文件导入到新项目的根目录中，因为我不想手动同步这两个文件。但是，当我执行以下命令时出现错误：

$ git submodule add -b master -f --name latexci -- \
    https://github.com/donizyo/LaTeX-Travis.git .
fatal: empty string is not a valid pathspec. please use . instead if you meant to match all paths
usage: git submodule--helper clone [--prefix=<path>] [--quiet] [--reference <repository>] [--name <name>] [--depth <depth>] --url <url> --path <path>

    --prefix <path>       alternative anchor for relative paths
    --path <path>         where the new submodule will be cloned to
    --name <string>       name of the new submodule
    --url <string> …

我想监听NavigationStart事件并判断它的url属性是否为/logout. 如果是这样，当我的侦听器检测到正确的NavigationStart事件时，路由器应该停止触发连续事件，例如RoutesRecognized、GuardsCheckStart、ChildActivationStart等。否则路由器应该继续路由。

import { Component, OnInit } from '@angular/core';
import { Router, NavigationStart } from '@angular/router';


@Component({
  selector: 'app-navbar',
  templateUrl: './navbar.component.html',
  styleUrls: ['./navbar.component.scss']
})
export class NavbarComponent implements OnInit {

  constructor(
    private router: Router,
  ) {
    router.events.filter(event => event instanceof NavigationStart).subscribe(
      (event: NavigationStart) => {
        if (event.url == '/logout') {
          this.logout();
          // TODO stop firing successive events
        }
      }
    );
  }

  ngOnInit() { …