深度学习-概率知识

伯努利分布和二项式分布

https://blog.csdn.net/adczsw/article/details/118331225

雅克比矩阵

逻辑回归

https://cloud.tencent.com/developer/article/1694338

卷积神经网络

https://zhuanlan.zhihu.com/p/21930884

如何确定神经网络的层数和隐藏层神经元数量

https://zhuanlan.zhihu.com/p/100419971

激活函数

激活函数的主要作用是提供网络的非线性表达建模能力,想象一下如果没有激活函数,那么神经网络只能表达线性映射,此刻即便是有再多的隐藏层,其整个网络和单层的神经网络都是等价的。

RELU sigmod tanh

0-1(二元输出层) 用 sigmod
其他的偏向 RELU

首先使用 ReLU,速度最快,然后观察模型的表现。
如果 ReLU 效果不是很好,可以尝试 Leaky ReLU 或 Maxout 等变种。
尝试 tanh 正切函数(以零点为中心,零点处梯度为 1)。
在深度不是特别深的 CNN 中,激活函数的影响一般不会太大。
Kaggle 比赛,试试 Mish?

Back Propagation(梯度反向传播)实例讲解(经典必看)

https://zhuanlan.zhihu.com/p/40378224

拟合说明

过拟合:训练出的模型在测试集上 Loss 很小,在训练集上 Loss 较大
欠拟合:训练出的模型在测试集上 Loss 很大,在训练集上 Loss 也很大
拟合:训练的刚刚好,在测试集上 Loss 很小,在训练集上 Loss 也很小

梯度下降优化算法

  1. 运动梯度下降算法
  2. RMSprop
  3. Adam

Batch Normalization 原理与实战 (加快收敛)

https://zhuanlan.zhihu.com/p/34879333

transforms.Normalize

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transform.ToTensor(),
transform.Normalize((0.5,0.5,0.5),(0.5,0.5,0.5))

那 transform.Normalize()是怎么工作的呢?以上面代码为例,ToTensor()能够把灰度范围从 0-255 变换到 0-1 之间,而后面的 transform.Normalize()则把 0-1 变换到(-1,1).具体地说,对每个通道而言,Normalize 执行以下操作:

image=(image-mean)/std

其中 mean 和 std 分别通过(0.5,0.5,0.5)和(0.5,0.5,0.5)进行指定。原来的 0-1 最小值 0 则变成(0-0.5)/0.5=-1,而最大值 1 则变成(1-0.5)/0.5=1

torch.nn.MaxPool2d 详解

https://blog.csdn.net/weixin_38481963/article/details/109962715

卷积数据输入说明

卷积输入输出是四维张量

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import torch
import torch.nn as nn

# 仅定义一个 3x3 的池化层窗口
m = nn.MaxPool2d(kernel_size=(3, 3))

# 定义输入
# 四个参数分别表示 (batch_size, C_in, H_in, W_in)
# 分别对应,批处理大小,输入通道数,图像高度(像素),图像宽度(像素)
# 为了简化表示,我们只模拟单张图片输入,单通道图片,图片大小是6x6
input = torch.randn(1, 1, 6, 6)

print(input)

output = m(input)

print(output)

torch.nn.Linear() 详解

https://www.cnblogs.com/blairgrowing/p/15976598.html

One/zero-shot

One/zero-shot learning 都是用来进行学习分类的算法。One-shot learning 就是对某一/某些类别只提供一个或者少量的训练样本;http://vision.stanford.edu/documents/Fei-FeiFergusPerona2006.pdfZero-shot learning 顾名思义就是对某一/某些类别完全不提供训练样本。

Word Embedding(文本数据转换为数值型数据)

文本表示的类型:

基于 one-hot、tf-idf、textrank 等的 bag-of-words;
主题模型:LSA(SVD)、pLSA、LDA;
基于词向量的固定表征:word2vec、fastText、glove
基于词向量的动态表征:ELMO、GPT、bert

nn.Embedding 的用法和理解

https://blog.csdn.net/qq_39540454/article/details/115215056

docker命令介绍

mac 下,挂载 docker 容器日志

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docker run -it -v /var/lib/docker/containers:/var/lib/docker/containers alpine sh /

chatgpt-intro

ModuleNotFoundError: No module named ‘html.parser’; ‘html’ is not a package

/Users/huangzhenzeng/Documents/ChatGpt/env/bin/python -m pip install –upgrade pip

ERROR: Can not execute setup.py since setuptools is not available in the build environment

pip install –upgrade setuptools

选房知识点

选房前,一定要踩点楼盘

朝向顺序

东南 -》西南 -》东北次选 -》 西北不要了

优先考虑点

通勤 -》教育 -》户型 -》朝向

考虑点

1.选南向看景的,不选南向靠路的 2.选择次楼王栋的,不选楼王栋的 3.有的选的情况下,不选有底商的 4.选靠路窄的,不选路宽的 5.选靠普通马路的,不选挨着高架的 6.选普通的景,不选楼前是儿童乐园区的 7.选小区中间的,不选挨着路边的

参考

深圳住建局 几个人才房 选房参考

  1. 深铁熙府项目选房结果公示:http://zjj.sz.gov.cn/ztfw/zfbz/fpjg/content/post_10500899.html
  2. 新城华苑项目选房结果公示:http://www.baoan.gov.cn/bajshej/gkmlpt/content/10/10507/post_10507490.html#5445

android更新apk方式

禁默安装

App 内升级调用 PackageInstaller

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public static void installApk1(
final @NonNull File apkFile, final @NonNull PermissionsActivity permissionsActivity) {
String apkName = "appInstall.apk";
long apkFileLength = apkFile.length();

PackageManager pm = permissionsActivity.getPackageManager();
PackageInstaller packageInstaller = pm.getPackageInstaller();
packageInstaller.registerSessionCallback(new PackageInstaller.SessionCallback() {
@Override
public void onCreated(int sessionId) {
Log.e(TAG, "Install Start sessionId-> " + sessionId);
}

@Override
public void onBadgingChanged(int sessionId) {}

@Override
public void onActiveChanged(int sessionId, boolean active) {}

@Override
public void onProgressChanged(int sessionId, float progress) {}

@Override
public void onFinished(int sessionId, boolean success) {
if (success) {
Log.e(TAG, "Silent Install Success");
} else {
Log.e(TAG, "Silent Install Fail");
}
}
});

int count;
int sessionId;
byte[] buffer = new byte[65536];

InputStream inputStream;
OutputStream outputStream;
PackageInstaller.Session session = null;
PackageInstaller.SessionParams sessionParams;

try {
sessionParams = new PackageInstaller.SessionParams(PackageInstaller.SessionParams.MODE_FULL_INSTALL);
sessionId = packageInstaller.createSession(sessionParams);
session = packageInstaller.openSession(sessionId);

inputStream = new FileInputStream(apkFile);
outputStream = session.openWrite(apkName, 0, apkFileLength);

while((count = inputStream.read(buffer)) != -1) {
outputStream.write(buffer, 0, count);
float progress = ((float)count / (float)apkFileLength);
session.setStagingProgress(progress);
}
session.fsync(outputStream);

inputStream.close();
outputStream.flush();
outputStream.close();

Intent intent = new Intent();
intent.setAction("xinan.intent.action.APP_INSTALL");
PendingIntent pendingIntent = PendingIntent.getBroadcast(permissionsActivity.getBaseContext(), 0, intent, 0);
session.commit(pendingIntent.getIntentSender());
} catch (Exception e) {
e.printStackTrace();
if (session != null) {
session.abandon();
}
} finally {
}
}

注册系统服务

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public class AutoStartAppReceiver extends BroadcastReceiver {
private final String TAG = "AutoStartReceiver";
private final String ACTION_BOOT = "android.intent.action.BOOT_COMPLETED";
private final String ACTION_CUSTOM_BOOT = "xinan.intent.action.BOOT_COMPLETED";
private final String ACTION_CUSTOM_AFTER_SYSTEM_UI = "xinan.intent.action.AfterStartSystemUI";
private final String ACTION_APP_INSTALL = "xinan.intent.action.APP_INSTALL";

/**
* 接收广播消息后都会进入 onReceive 方法,然后要做的就是对相应的消息做出相应的处理
*
* @param context 表示广播接收器所运行的上下文
* @param intent 表示广播接收器收到的Intent
*/
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
Log.i(TAG, "onReceive:" + action);
if (ACTION_BOOT.equals(action)
|| ACTION_CUSTOM_AFTER_SYSTEM_UI.equals(action)
|| ACTION_CUSTOM_BOOT.equals(action)) {
launchApp(context);
} else if (ACTION_APP_INSTALL.equals(action)) {
Bundle extras = intent.getExtras();
int status = extras.getInt(PackageInstaller.EXTRA_STATUS);
String message = extras.getString(PackageInstaller.EXTRA_STATUS_MESSAGE);
Log.i(TAG, "onReceive status:" + status + " message:" + message);

switch (status) {
case PackageInstaller.STATUS_PENDING_USER_ACTION:
break;
case PackageInstaller.STATUS_SUCCESS:
Log.d(TAG, "Install succeeded!");
launchApp(context);
break;
case PackageInstaller.STATUS_FAILURE:
case PackageInstaller.STATUS_FAILURE_ABORTED:
case PackageInstaller.STATUS_FAILURE_BLOCKED:
case PackageInstaller.STATUS_FAILURE_CONFLICT:
case PackageInstaller.STATUS_FAILURE_INCOMPATIBLE:
case PackageInstaller.STATUS_FAILURE_INVALID:
case PackageInstaller.STATUS_FAILURE_STORAGE:
Log.e(TAG, "Install failed!" + status + ", " + message);
break;
default:
Log.e(TAG, "Unrecognized status received from installer: " + status);
}
}
}

private void launchApp(Context context) {
try {
String packageName = "com.xinan.ubox";
PackageManager pm = context.getPackageManager();
if (checkApp(pm, packageName)) {
if (!isRunning(context, packageName)) {
Log.i(TAG, "app start:" + packageName);
Intent intentMainActivity = pm.getLaunchIntentForPackage(packageName);
intentMainActivity.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intentMainActivity);
} else {
Log.i(TAG, "app is running:" + packageName);
}
} else {
Log.i(TAG, "app not exist:" + packageName);
}
} catch (Exception e) {
Log.i(TAG, "onReceive error:" + e.getLocalizedMessage());
}
}

private boolean checkApp(PackageManager pm, String packageName) {
try {
PackageInfo packageInfo = pm.getPackageInfo(packageName, 0);
return packageInfo != null;
} catch (Exception e) {
return false;
}
}

public boolean isRunning(Context context, String packageName) {
try {
ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
//获取当前所有存活task的信息
List<ActivityManager.RunningTaskInfo> processInfos = activityManager.getRunningTasks(Integer.MAX_VALUE);
//遍历,若task的name与当前task的name相同,则返回true,否则,返回false
for (ActivityManager.RunningTaskInfo process : processInfos) {
if (process.baseActivity.getPackageName().equals(packageName)
|| process.topActivity.getPackageName().equals(packageName)) {
return true;
}
}

return false;
} catch (Exception e) {
Log.i(TAG, "isRunning error:" + e.getLocalizedMessage());

return false;
}
}
}

manifest 注册接收器

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<!--注册接收系统开机广播消息的广播接收者-->
<receiver
android:name=".AutoStartAppReceiver"
android:enabled="true"
android:exported="true">
<intent-filter android:priority="1000">
<action android:name="android.intent.action.BOOT_COMPLETED" />
<action android:name="xinan.intent.action.AfterStartSystemUI" />
<action android:name="xinan.intent.action.APP_INSTALL" />
<action android:name="xinan.intent.action.BOOT_COMPLETED" />
<category android:name="android.intent.category.HOME" />
</intent-filter>
</receiver>

参考资料

https://blog.csdn.net/sinat_35622297/article/details/83995957?spm=1001.2101.3001.6650.11&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-11-83995957-blog-128485823.235%5Ev27%5Epc_relevant_multi_platform_whitelistv3&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-11-83995957-blog-128485823.235%5Ev27%5Epc_relevant_multi_platform_whitelistv3&utm_relevant_index=17

https://stackoverflow.com/questions/58085899/android-10-no-activity-found-to-handle-intent

https://zhuanlan.zhihu.com/p/183960413

https://android.googlesource.com/platform/development/+/master/samples/ApiDemos/src/com/example/android/apis/content/InstallApkSessionApi.java

android中backup介绍

  1. adb 备份
    adb backup -f ~/Desktop/log/a.ab -apk com.package.activity

  2. 下载 abe 包

  3. ab 文件解包
    java -jar ~/Downloads/abe/abe.jar unpack ~/Desktop/log/a.ab ~/Desktop/log/a.rar

  4. rar 软件解压 a.rar,即可

android各系统中,formatter适配

Android 中,格式化文件大小(Formatter.formatFileSize),Android8 之前用 1024 为单位,之后采用 1000 为单位。

Formatter 的源码解析

查看 Android 28(Android P)源码

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public static BytesResult formatBytes(Resources res, long sizeBytes, int flags) {
final int unit = ((flags & FLAG_IEC_UNITS) != 0) ? 1024 : 1000;
final boolean isNegative = (sizeBytes < 0);
float result = isNegative ? -sizeBytes : sizeBytes;
int suffix = com.android.internal.R.string.byteShort;
long mult = 1;
if (result > 900) {
suffix = com.android.internal.R.string.kilobyteShort;
mult = unit;
result = result / unit;
}
......
}

formatFileSize 方法源码如下:

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 /* <p>As of O, the prefixes are used in their standard meanings in the SI system, so kB = 1000
* bytes, MB = 1,000,000 bytes, etc.</p>
*
* <p class="note">In {@link android.os.Build.VERSION_CODES#N} and earlier, powers of 1024 are
* used instead, with KB = 1024 bytes, MB = 1,048,576 bytes, etc.</p>
*/
public static String formatFileSize(@Nullable Context context, long sizeBytes) {
if (context == null) {
return "";
}
final BytesResult res = formatBytes(context.getResources(), sizeBytes, FLAG_SI_UNITS);
return bidiWrap(context, context.getString(com.android.internal.R.string.fileSizeSuffix,
res.value, res.units));
}

意思就是在 Android 7 之后单位就变了,使用标准的单位制含义,即国际单位制,就像 1km = 1000 byte 一样;
在 Android 7 及更早的版本是 1024,即 1k = 1024B,这里就不贴代码了,感兴趣的同学可以去看源码。

解决方案

有两个方案,一个是反射设置 FLAG_SI_UNITS 的值,使得与 FLAG_IEC_UNITS 相与不为 0 ,
另外一个方案重新封装一个类,如下,用法与 Android 提供的一样

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public class Formatter {
/** * get file format size * * @param context context * @param roundedBytes file size * @return file format size (like 2.12k) */
public static String formatFileSize(Context context, long roundedBytes) {
return formatFileSize(context, roundedBytes, false, Locale.US);
}

public static String formatFileSize(Context context, long roundedBytes, Locale locale) {
return formatFileSize(context, roundedBytes, false, locale);
}


private static String formatFileSize(Context context, long roundedBytes, boolean shorter, Locale locale) {
if (context == null) {
return "";
}
float result = roundedBytes;
String suffix = "B";
if (result > 900) {
suffix = "KB";
result = result / 1024;
}
if (result > 900) {
suffix = "MB";
result = result / 1024;
}
if (result > 900) {
suffix = "GB";
result = result / 1024;
}
if (result > 900) {
suffix = "TB";
result = result / 1024;
}
if (result > 900) {
suffix = "PB";
result = result / 1024;
}
String value;
if (result < 1) {
value = String.format(locale, "%.2f", result);
} else if (result < 10) {
if (shorter) {
value = String.format(locale, "%.1f", result);
} else {
value = String.format(locale, "%.2f", result);
}
} else if (result < 100) {
if (shorter) {
value = String.format(locale, "%.0f", result);
} else {
value = String.format(locale, "%.2f", result);
}
} else {
value = String.format(locale, "%.0f", result);
}
return String.format("%s%s", value, suffix);
}

}