我stackNavigator用于在屏幕之间导航.我componentDidMount()在第二个活动中正在调用两个API .当我第一次加载它时,它会成功加载.然后我按回按钮返回第一个活动.然后,如果我再次进行第二次活动,则不会调用API,我会收到渲染错误.我无法找到任何解决方案.任何建议,将不胜感激.
我正在尝试使用 spark 应用程序访问 s3 数据。我正在应用 Spark SQL 来检索数据。它不采用 group by 子句。
DataFrame summaryQuery=sql.sql("Select score from summary order by updationDate desc);
summaryQuery.groupBy("sessionId").count().show();
summaryQuery.show();
我也直接尝试
DataFrame summaryQuery=sql.sql("Select score from summary group by sessionId order by updationDate desc);
summaryquery.show();
但在这两种情况下，我都遇到了 SQL 异常。
Exception in thread "main" org.apache.spark.sql.AnalysisException: expression 'score' is neither present in the group by, nor is it an aggregate function. Add to group by or wrap in first() (or first_value) if you don't care which value you get.;
请指定我如何查询数据。
I am using matplotlib library of python for plotting graphs. My program is to detect the outliers in the system. I am making an interface for this. I have to show this graph in browser on clicking the button. Here is my php file code :-
<?php
if (isset($_POST['button']))
{
echo shell_exec("python3 /var/www/html/python/anomalies.py 2>&1");
}
?>
<html>
<body>
<center>
<form method="post">
<table>
<tr>
<td>
Enter CSV file path:
</td>
<td>
<input type="text" name="path">
</td>
</tr>
</table>
<p>
<button name="button">Identify Anomalies</button> …我试图调用function每当我选择一个项目picker，并显示与所选择的项目alert。
这就是我在做什么：-
import React, { Component } from 'react';
import { AppRegistry, StyleSheet, TextInput, View, Alert, Button,Platform,ActivityIndicator, Text, Picker, ScrollView } from 'react-native';
export default class FirstProject extends Component {
constructor(props) {
super(props);
this.state = {
isLoading: true,
throttlemode:'',
}
}
GetSelectedThrottleModeItem=(throttlemode)=>{
Alert.alert(this.state.throttlemode)
}
render() {
return (
<View style={styles.MainContainerAddCamp}>
<Text style={{fontSize: 12}}> Throttle Mode</Text>
<Picker style={styles.PickerStyleClass}
selectedValue={this.state.throttlemode}
onValueChange={(throttlemodeValue, throttlemodeIndex) => this.GetSelectedThrottleModeItem(this.setState({throttlemode:throttlemodeValue}))}>
<Picker.Item label="Asap" value="asap" />
<Picker.Item label="Even" value="even" />
</Picker>
</View>
);
} …