如何启动Perl的交互式控制台，类似于Ruby的irb命令或python的python命令?

我试图从一组帧使用FFMPEG使用libx264编解码器编码。mp4视频。

这是我正在运行的命令:

/usr/local/bin/ffmpeg -r 24 -i frame_%05d.jpg -vcodec libx264 -y -an video.mp4

我有时会得到以下错误:

[libx264 @ 0xa3b85a0] height not divisible by 2 (520x369)

在搜索了一下之后，似乎这个问题与缩放算法有关，可以通过添加-vf参数来修复。

然而，在我的例子中，我不想做任何缩放。理想情况下，我希望保持尺寸与框架完全相同。任何建议吗?是否存在h264强制的某种纵横比?

我想使用一个开关在网页上的段落标签的布局。

我使用后伪元素:

p:after {content: url("../img/paragraph.gif");}

现在我需要从页面中删除此CSS代码。

这怎么容易做到呢?

我还想补充一点:

页面上已经使用了jQuery 和我不想包括或删除文件包含CSS。

为什么在训练期间需要调用zero_grad() ?

|  zero_grad(self)
|      Sets gradients of all model parameters to zero.

我如何克隆一个数组列表，也克隆其项目在Java?

例如，我有:

ArrayList<Dog> dogs = getDogs();
ArrayList<Dog> clonedList = ....something to do with dogs....

我希望clonedList中的对象与dogs list中的对象不一样。

我有一个ksh脚本，它返回一个长列表的值，换行符分隔，我想只看到唯一的/不同的值。这是可能的吗?

例如，我的输出是一个目录下的文件后缀:

焦油 广州 java 广州 java 焦油 类 类

我想看到这样的列表:

焦油 广州 java 类

让我们假设我们用python编写了这样一个简单的守护进程:

def mainloop():
    while True:
        # 1. do
        # 2. some
        # 3. important
        # 4. job
        # 5. sleep

mainloop()

我们使用start-stop-daemon守护它，默认情况下发送SIGTERM (TERM)信号在——stop上。

让我们假设当前执行的步骤是#2。此时，我们发送TERM信号。

结果是执行立即终止。

我发现我可以使用signal.signal(信号。SIGTERM，处理程序)，但问题是它仍然中断当前执行并将控制传递给处理程序。

所以，我的问题是-是否有可能不中断当前的执行，而是在一个分离的线程中处理TERM信号(?)，以便我能够设置shutdown_flag = True，以便mainloop()有机会优雅地停止?

是否可以使用新的Firebase数据库Cloud Firestore来计算一个集合有多少项?

如果是，我该怎么做?

这是我的错误:

(mysite)zjm1126@zjm1126-G41MT-S2:~/zjm_test/mysite$ pip install lxml
Downloading/unpacking lxml
  Running setup.py egg_info for package lxml
    Building lxml version 2.3.
    Building without Cython.
    ERROR: /bin/sh: xslt-config: not found

    ** make sure the development packages of libxml2 and libxslt are installed **

    Using build configuration of libxslt
Installing collected packages: lxml
  Running setup.py install for lxml
    Building lxml version 2.3.
    Building without Cython.
    ERROR: /bin/sh: xslt-config: not found

    ** make sure the development packages of libxml2 and libxslt are installed **

    Using build configuration of libxslt
    building 'lxml.etree' extension
    gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -I/usr/include/python2.6 -c src/lxml/lxml.etree.c -o build/temp.linux-i686-2.6/src/lxml/lxml.etree.o -w
    src/lxml/lxml.etree.c:4: fatal error: Python.h: 没有那个文件或目录
    compilation terminated.
    error: command 'gcc' failed with exit status 1
    Complete output from command /home/zjm1126/zjm_test/mysite/bin/python -c "import setuptools;__file__='/home/zjm1126/zjm_test/mysite/build/lxml/setup.py';execfile(__file__)" install --single-version-externally-managed --record /tmp/pip-jOhgvD-record/install-record.txt --install-headers /home/zjm1126/zjm_test/mysite/include/site/python2.6:
    Building lxml version 2.3.

Building without Cython.

ERROR: /bin/sh: xslt-config: not found



** make sure the development packages of libxml2 and libxslt are installed **



Using build configuration of libxslt

running install

running build

running build_py

running build_ext

building 'lxml.etree' extension

gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -I/usr/include/python2.6 -c src/lxml/lxml.etree.c -o build/temp.linux-i686-2.6/src/lxml/lxml.etree.o -w

src/lxml/lxml.etree.c:4: fatal error: Python.h: 没有那个文件或目录

compilation terminated.

error: command 'gcc' failed with exit status 1

----------------------------------------
Command /home/zjm1126/zjm_test/mysite/bin/python -c "import setuptools;__file__='/home/zjm1126/zjm_test/mysite/build/lxml/setup.py';execfile(__file__)" install --single-version-externally-managed --record /tmp/pip-jOhgvD-record/install-record.txt --install-headers /home/zjm1126/zjm_test/mysite/include/site/python2.6 failed with error code 1
Storing complete log in /home/zjm1126/.pip/pip.log

我该怎么办?

更新:

(mysite)zjm1126@zjm1126-G41MT-S2:~/zjm_test/mysite$ pip install lxml
Downloading/unpacking lxml
  Running setup.py egg_info for package lxml
    Building lxml version 2.3.
    Building without Cython.
    Using build configuration of libxslt 1.1.26
    Building against libxml2/libxslt in the following directory: /usr/lib
Installing collected packages: lxml
  Running setup.py install for lxml
    Building lxml version 2.3.
    Building without Cython.
    Using build configuration of libxslt 1.1.26
    Building against libxml2/libxslt in the following directory: /usr/lib
    building 'lxml.etree' extension
    gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -I/usr/include/libxml2 -I/usr/include/python2.6 -c src/lxml/lxml.etree.c -o build/temp.linux-i686-2.6/src/lxml/lxml.etree.o -w
    src/lxml/lxml.etree.c:4: fatal error: Python.h: 没有那个文件或目录
    compilation terminated.
    error: command 'gcc' failed with exit status 1
    Complete output from command /home/zjm1126/zjm_test/mysite/bin/python -c "import setuptools;__file__='/home/zjm1126/zjm_test/mysite/build/lxml/setup.py';execfile(__file__)" install --single-version-externally-managed --record /tmp/pip-NJw2ws-record/install-record.txt --install-headers /home/zjm1126/zjm_test/mysite/include/site/python2.6:
    Building lxml version 2.3.

Building without Cython.

Using build configuration of libxslt 1.1.26

Building against libxml2/libxslt in the following directory: /usr/lib

running install

running build

running build_py

running build_ext

building 'lxml.etree' extension

gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -I/usr/include/libxml2 -I/usr/include/python2.6 -c src/lxml/lxml.etree.c -o build/temp.linux-i686-2.6/src/lxml/lxml.etree.o -w

src/lxml/lxml.etree.c:4: fatal error: Python.h: 没有那个文件或目录

compilation terminated.

error: command 'gcc' failed with exit status 1

----------------------------------------
Command /home/zjm1126/zjm_test/mysite/bin/python -c "import setuptools;__file__='/home/zjm1126/zjm_test/mysite/build/lxml/setup.py';execfile(__file__)" install --single-version-externally-managed --record /tmp/pip-NJw2ws-record/install-record.txt --install-headers /home/zjm1126/zjm_test/mysite/include/site/python2.6 failed with error code 1
Storing complete log in /home/zjm1126/.pip/pip.log

日志:

------------------------------------------------------------
/home/zjm1126/zjm_test/mysite/bin/pip run on Thu Mar  3 17:07:27 2011
Downloading/unpacking mysql-python
  Running setup.py egg_info for package mysql-python
    running egg_info
    creating pip-egg-info/MySQL_python.egg-info
    writing pip-egg-info/MySQL_python.egg-info/PKG-INFO
    writing top-level names to pip-egg-info/MySQL_python.egg-info/top_level.txt
    writing dependency_links to pip-egg-info/MySQL_python.egg-info/dependency_links.txt
    writing pip-egg-info/MySQL_python.egg-info/PKG-INFO
    writing top-level names to pip-egg-info/MySQL_python.egg-info/top_level.txt
    writing dependency_links to pip-egg-info/MySQL_python.egg-info/dependency_links.txt
    writing manifest file 'pip-egg-info/MySQL_python.egg-info/SOURCES.txt'
    warning: manifest_maker: standard file '-c' not found
    reading manifest file 'pip-egg-info/MySQL_python.egg-info/SOURCES.txt'
    reading manifest template 'MANIFEST.in'
    warning: no files found matching 'MANIFEST'
    warning: no files found matching 'ChangeLog'
    warning: no files found matching 'GPL'
    writing manifest file 'pip-egg-info/MySQL_python.egg-info/SOURCES.txt'
Installing collected packages: mysql-python
  Running setup.py install for mysql-python
    Running command /home/zjm1126/zjm_test/mysite/bin/python -c "import setuptools;__file__='/home/zjm1126/zjm_test/mysite/build/mysql-python/setup.py';execfile(__file__)" install --single-version-externally-managed --record /tmp/pip-XuVIux-record/install-record.txt --install-headers /home/zjm1126/zjm_test/mysite/include/site/python2.6
    running install
    running build
    running build_py
    creating build
    creating build/lib.linux-i686-2.6
    copying _mysql_exceptions.py -> build/lib.linux-i686-2.6
    creating build/lib.linux-i686-2.6/MySQLdb
    copying MySQLdb/__init__.py -> build/lib.linux-i686-2.6/MySQLdb
    copying MySQLdb/converters.py -> build/lib.linux-i686-2.6/MySQLdb
    copying MySQLdb/connections.py -> build/lib.linux-i686-2.6/MySQLdb
    copying MySQLdb/cursors.py -> build/lib.linux-i686-2.6/MySQLdb
    copying MySQLdb/release.py -> build/lib.linux-i686-2.6/MySQLdb
    copying MySQLdb/times.py -> build/lib.linux-i686-2.6/MySQLdb
    creating build/lib.linux-i686-2.6/MySQLdb/constants
    copying MySQLdb/constants/__init__.py -> build/lib.linux-i686-2.6/MySQLdb/constants
    copying MySQLdb/constants/CR.py -> build/lib.linux-i686-2.6/MySQLdb/constants
    copying MySQLdb/constants/FIELD_TYPE.py -> build/lib.linux-i686-2.6/MySQLdb/constants
    copying MySQLdb/constants/ER.py -> build/lib.linux-i686-2.6/MySQLdb/constants
    copying MySQLdb/constants/FLAG.py -> build/lib.linux-i686-2.6/MySQLdb/constants
    copying MySQLdb/constants/REFRESH.py -> build/lib.linux-i686-2.6/MySQLdb/constants
    copying MySQLdb/constants/CLIENT.py -> build/lib.linux-i686-2.6/MySQLdb/constants
    running build_ext
    building '_mysql' extension
    creating build/temp.linux-i686-2.6
    gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -Dversion_info=(1,2,3,'final',0) -D__version__=1.2.3 -I/usr/include/mysql -I/usr/include/python2.6 -c _mysql.c -o build/temp.linux-i686-2.6/_mysql.o -DBIG_JOINS=1 -fno-strict-aliasing -DUNIV_LINUX -DUNIV_LINUX
    In file included from _mysql.c:29:
    pymemcompat.h:10: fatal error: Python.h: 没有那个文件或目录
    compilation terminated.
    error: command 'gcc' failed with exit status 1
    Complete output from command /home/zjm1126/zjm_test/mysite/bin/python -c "import setuptools;__file__='/home/zjm1126/zjm_test/mysite/build/mysql-python/setup.py';execfile(__file__)" install --single-version-externally-managed --record /tmp/pip-XuVIux-record/install-record.txt --install-headers /home/zjm1126/zjm_test/mysite/include/site/python2.6:
    running install

running build

running build_py

creating build

creating build/lib.linux-i686-2.6

copying _mysql_exceptions.py -> build/lib.linux-i686-2.6

creating build/lib.linux-i686-2.6/MySQLdb

copying MySQLdb/__init__.py -> build/lib.linux-i686-2.6/MySQLdb

copying MySQLdb/converters.py -> build/lib.linux-i686-2.6/MySQLdb

copying MySQLdb/connections.py -> build/lib.linux-i686-2.6/MySQLdb

copying MySQLdb/cursors.py -> build/lib.linux-i686-2.6/MySQLdb

copying MySQLdb/release.py -> build/lib.linux-i686-2.6/MySQLdb

copying MySQLdb/times.py -> build/lib.linux-i686-2.6/MySQLdb

creating build/lib.linux-i686-2.6/MySQLdb/constants

copying MySQLdb/constants/__init__.py -> build/lib.linux-i686-2.6/MySQLdb/constants

copying MySQLdb/constants/CR.py -> build/lib.linux-i686-2.6/MySQLdb/constants

copying MySQLdb/constants/FIELD_TYPE.py -> build/lib.linux-i686-2.6/MySQLdb/constants

copying MySQLdb/constants/ER.py -> build/lib.linux-i686-2.6/MySQLdb/constants

copying MySQLdb/constants/FLAG.py -> build/lib.linux-i686-2.6/MySQLdb/constants

copying MySQLdb/constants/REFRESH.py -> build/lib.linux-i686-2.6/MySQLdb/constants

copying MySQLdb/constants/CLIENT.py -> build/lib.linux-i686-2.6/MySQLdb/constants

running build_ext

building '_mysql' extension

creating build/temp.linux-i686-2.6

gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -Dversion_info=(1,2,3,'final',0) -D__version__=1.2.3 -I/usr/include/mysql -I/usr/include/python2.6 -c _mysql.c -o build/temp.linux-i686-2.6/_mysql.o -DBIG_JOINS=1 -fno-strict-aliasing -DUNIV_LINUX -DUNIV_LINUX

In file included from _mysql.c:29:

pymemcompat.h:10: fatal error: Python.h: 没有那个文件或目录

compilation terminated.

error: command 'gcc' failed with exit status 1

----------------------------------------
Command /home/zjm1126/zjm_test/mysite/bin/python -c "import setuptools;__file__='/home/zjm1126/zjm_test/mysite/build/mysql-python/setup.py';execfile(__file__)" install --single-version-externally-managed --record /tmp/pip-XuVIux-record/install-record.txt --install-headers /home/zjm1126/zjm_test/mysite/include/site/python2.6 failed with error code 1
Exception information:
Traceback (most recent call last):
  File "/home/zjm1126/zjm_test/mysite/lib/python2.6/site-packages/pip-0.8.1-py2.6.egg/pip/basecommand.py", line 130, in main
    self.run(options, args)
  File "/home/zjm1126/zjm_test/mysite/lib/python2.6/site-packages/pip-0.8.1-py2.6.egg/pip/commands/install.py", line 228, in run
    requirement_set.install(install_options, global_options)
  File "/home/zjm1126/zjm_test/mysite/lib/python2.6/site-packages/pip-0.8.1-py2.6.egg/pip/req.py", line 1043, in install
    requirement.install(install_options, global_options)
  File "/home/zjm1126/zjm_test/mysite/lib/python2.6/site-packages/pip-0.8.1-py2.6.egg/pip/req.py", line 559, in install
    cwd=self.source_dir, filter_stdout=self._filter_install, show_stdout=False)
  File "/home/zjm1126/zjm_test/mysite/lib/python2.6/site-packages/pip-0.8.1-py2.6.egg/pip/__init__.py", line 249, in call_subprocess
    % (command_desc, proc.returncode))
InstallationError: Command /home/zjm1126/zjm_test/mysite/bin/python -c "import setuptools;__file__='/home/zjm1126/zjm_test/mysite/build/mysql-python/setup.py';execfile(__file__)" install --single-version-externally-managed --record /tmp/pip-XuVIux-record/install-record.txt --install-headers /home/zjm1126/zjm_test/mysite/include/site/python2.6 failed with error code 1

我试图创建一个基本的OS X框架，现在我刚刚创建了一个测试框架:TestMacFramework.framework，我试图将它导入到一个全新的OS X应用程序项目。

我已经构建了.framework文件并将其导入到新项目中，框架链接正常，我可以引用我添加到框架构建阶段部分的公共头文件。

然而，当我尝试运行容器应用程序时，我得到以下错误:

dyld: Library not loaded: /Library/Frameworks/TestMacFramework.framework/Versions/A/TestMacFramework
  Referenced from: /Users/samharman/Library/Developer/Xcode/DerivedData/TestMacContainer-dzabuelobzfknafuhmgooqhqrgzl/Build/Products/Debug/TestMacContainer.app/Contents/MacOS/TestMacContainer
  Reason: image not found

在谷歌了一下之后，我意识到我需要在我的容器应用程序构建阶段添加一个复制文件部分，所以我已经这样做了，并像这样设置它…

然而，我仍然得到运行时错误。显然我在这里做错了什么，但是苹果开发者库的资源引用了Xcode 2，所以不是很有帮助!

我错过了什么?

更新:

我可以在构建日志中看到我的TestMacFramework.framework被复制到.app contents/frameworks目录中，但它没有被安装到HD上的Library/ frameworks目录中

更新2:

如果我手动将TestMacFramework.framework复制到Library/Frameworks目录中，构建链接是正确的