Author Archives: Robins

Output the error log of CMD in windows to the txt file: use > > to log.txt

sometimes in Windows to run some CMD commands or command files: batch command files such as.bat,.cmd files,.exe files CMD window will flash back, there will be some error reasons, we would like to see, in order to targeted to solve the problem. At this time can think of is output error to the log file to preserve the view or record the screen software with high frame rate CMD window flash back inside displayed error information.

for now, I’m only going to talk about output to the log .

situation 1: run the command flash back directly in CMD.

solution: enter the command in the newly opened CMD window in the format: command > > log.txt

for example: ipconfig/all> > D:\test\log.txt is to output IP configuration information to the path D:\test\log.txt log file,

if the path is log.txt means output to the current directory,

like ipconfig/all> > Log.txt outputs logs to the C:\Windows\System32 directory, and the program that runs the ipconfig/all command ipconfig.exe is in the C:\Windows\System32 directory


Situation 2: run the.exe (.cmd,.bat, etc.) program

in CMD

solution: in the directory where exe program is located, hold Shift and right-click in the blank, enter the command in the open CMD window, the format is: exe program name > > log.txt

log output path as in scenario 1.

note: double-clicking the.exe,.cmd,.bat file will have the same effect as typing the program name on the CMD command line in scenario 2 to start the program.

USES scenario 2 to process and run visible exe,.cmd,.bat files. It has more advantages than double-clicking to run them. It is more controllable in the whole process, and more parameters can be added to the command line to assist running these files, such as making the run log TXT file.

Extension of image edge by Python opencv

original image

expands the image outwards according to the pixel value of the image boundary, expanding 50 pixels in each direction.
a = cv2. CopyMakeBorder (img, 50,50,50,50, cv2. BORDER_REPLICATE)

near the boundary of the 50 pixels fold out (axisymmetric) :
a = cv2. CopyMakeBorder (img, 50,50,50,50, cv2 BORDER_REFLECT)

constant fill:

a = cv2.copymakeborder (img,50,50,50, cv2.border_constant,value=[0,255,0])

Attributeerror: ‘dataframe’ object has no attribute ‘IX’ error

“AttributeError: ‘DataFrame’ object has no attribute ‘ix'”

recently reported when using the ix method of DataFrame

after searching on the Internet, is removed from the series.ix and dataframe.ix method at the beginning of pandas’ 1.0.0 version.

my solution: use the loc method of DataFrame or the iloc method instead.

check pandas

for details


reference: https://hacpai.com/article/1581255121678

Vue error: did you register the component correctly? For.., make sure to provide the “name” option (solved)

P> question:
did you register the component?For recursive components, make sure to provid the "name" option

For recursive components, make sure to provid the “name” option

import ComponentA from './ComponentA.vue'
import ComponentB from './ComponentB.vue'
export default {
  component: {
    ComponentA,ComponentB
  },
  // ...
}

solution:
to correct component 

import ComponentA from './ComponentA.vue'
import ComponentB from './ComponentB.vue'
export default {
  components: {
    ComponentA,ComponentB
  },
  // ...
}

How many pieces of data can list store in Java?

from the perspective of language, java.util.List is an interface, under which there are multiple N implementations, the most commonly used are ArrayList and LinkedList and its various inheritance or synchronization implementation (such as Vector/Queue/Stack)
ArrayList inside is to take the array storage, then the upper limit is Integer.MAX_VALUE
LinkedList inside is a LinkedList, theoretically infinite

also, everything in the List is in memory (although you can implement one yourself), so how much you can put depends on the size and type of stuff you’re putting. The
size aspect is easy to calculate, if one object is 1K, then 400,000 will take up at least 400M memory (not counting other usage).
virtual machine memory classification, if it is a common object, generally use the Heap space, if it is a constant or something like string.intern (), then use the Permanent Generation.

in actual development, the default memory size of virtual machine varies according to different virtual machine implementations. The maximum heap size can be adjusted with -xmx when the application is launched, such as adjusting the maximum heap size to 2G:

java -Xmx2048m cn.gefostudio.App

adjust the maximum size of the immortal band to 1G:

java -XX:MaxPermSize=1024m cn.gefostudio.App

HTML using title attribute to display text with mouse hover

mouse hover display text, HTML use title attribute can achieve the effect of text display, this attribute is more practical, the need for friends can refer to

< A href=# title=” here is the text displayed “> hello< /a>

when we hover over hello last time we will have text and here is the text that is displayed.

Pass parameters to the YML file, ansible playbook command

extract: https://ansible-book.gitbooks.io/ansible-first-book/content/yong_ming_ling_xing_chuan_di_can_shu.html

= ansible-books.io/ansible-first-book/content/yong_ming_ling_xing_chuan_di_can_shu.html

passes the parameter

from the command line

defines the command line variable

in the release.yml file, hosts and user are defined as variables that need to be passed from the command line.

  • hosts: ‘{{host}}
    remote_user:’ {{user}}

    the tasks:

    • …
      USES the command line variable

to pass value on the command line: 

 ansible-playbook e33_var_in_command.yml --extra-vars "hosts=web user=root"

The

parameter can also be passed in json format: 

ansible-playbook e33_var_in_command.yml --extra-vars "{'hosts':'vm-rhel7-1', 'user':'root'}"

can also put parameters in the file: 


ansible-playbook e33_var_in_command.yml --extra-vars "@vars.json"

Module in linux driver_ platform_ Learning driver macro


Linux driver module_platform_driver macro learning

It is common to see this macro module_platform_driver on Linux devices. The following figure shows a character device driver. Today we’re going to learn about this macro.

2, the macro is in kernel/include/Linux/platform_device. H defined inside. We find that this calls another macro, module_driver.

. So where is the module_driver macro defined?For once, the macro is in kernel/include/Linux/device. The definition of h.

The macro module_platform_driver can be used to write much less code. The purpose of the macro is to define the platform driver registration function and the platform driver unregistration function with the specified name, and to register and unregister the platform driver within the function body with the functions platform_driver_register() and Platform_driver_unregister (), respectively.


static int x_init(void)
{
return platform_driver_register(& xxx);
}
module_init(xxx_init);
static void __exit xxx_init(void)
{
return platform_driver_unregister(& xxx);
}
module_exit(xxx_exit);

Time, strftime and strptime in Python

The most common

time.time() returns a floating point number in seconds. But the type that strfTime handles is time.struct_time, which is actually a tuple. Both strpTime and localTime will return this type. 

>>> import time
>>> t = time.time()
>>> t
1202872416.4920001
>>> type(t)
<type 'float'>
>>> t = time.localtime()
>>> t
(2008, 2, 13, 10, 56, 44, 2, 44, 0)
>>> type(t)
<type 'time.struct_time'>
>>> time.strftime('%Y-%m-%d', t)
'2008-02-13'
>>> time.strptime('2008-02-14', '%Y-%m-%d')
(2008, 2, 14, 0, 0, 0, 3, 45, -1)

1, strftime usage

strftime can be used to get the current time, you can format the time as a string, and so on, which is pretty handy. However, it should be noted that the acquired time is the time of the server, and pay attention to the time zone issues, such as GAE lying that the time is the 0 time zone of GMT, which needs to be converted by itself.

Strftime ()

strftime ()
we can use the strftime () function to format the time in the desired format 

#!/usr/bin/python
import time

t = (2009, 2, 17, 17, 3, 38, 1, 48, 0)
t = time.mktime(t)
print time.strftime("%b %d %Y %H:%M:%S", time.gmtime(t))

#输出：Feb 17 2009 09:03:38

2. Strptime

The

Python time strptime() function parses a time string into a time tuple according to the specified format.
python time date formatting symbol:

  • %y two-digit years are (00-99)
  • %y four-digit years are (000-9999)
  • %m months (01-12)
  • %d months (0-31)
  • %H 24 H hours (0-23)

    • 0

  • 1% I 12-hour hours (01-12)

    • 3% m minutes (00=59)

    4

  • 5% S Second (00-59)
  • %a local simplified name of the week
  • %a local simplified name of the week
  • %b local simplified name of the month
  • %b local complete name of the month
  • %c local corresponding date and time expression

    • 0

  • 1% a day (001-366)
    • 2
  • 3% p local a.m. The number of weeks of the year (00-53) Sunday is the beginning of the week
  • %w (0-6), Sunday is the beginning of the week
  • %w (00-53) Monday is the beginning of the week
  • %x local corresponding date is
  • %x local corresponding time is

    • 0

  • 1 %Z current time zone name

    • 2

  • 3 %% %% %U number itself

    • 4

5

instance: 

#!/usr/bin/python
import time

struct_time = time.strptime("30 Nov 00", "%d %b %y")
print "returned tuple: %s " % struct_time

#输出：returned tuple: (2000, 11, 30, 0, 0, 0, 3, 335, -1)

IntelliJ idea sets the default working directory

project more and more, using eclipse felt too card, decided to try the idea.

under multiple modules, system.getproperty (“user.dir”) gets the path to the module when you run the project.

to set the default Working Directory

setting method:

Run -> Edit Configurations -> Working directory


Defaults-> Application

set Working directory to $MODULE_DIR$so that each module gets its own project root path