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3 min readTo delete added lines between two files in bash, you can use the diff command to compare the two files and then use grep to filter out the added lines. You can do this by running the following command: diff file1.txt file2.txt | grep '^> ' | cut -c3- | comm -23 - <(sort -u file1.txt) | sed '/^>/d' > deleted_lines.txt This command will compare file1.txt and file2.
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4 min readIn Bash, you can assign different outputs to different variables by using command substitution along with the assignment operator. Command substitution allows you to capture the output generated by a command and assign it to a variable.To assign different outputs to different variables, you can use command substitution within a variable assignment statement. For example, you can assign the output of a command to a variable by enclosing the command within $() or backticks (`).
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4 min readTo grep all keywords from an array in a bash script, you can iterate through the array and use the grep command to search for each keyword. You can do this by looping through the array elements and using grep -w to match whole words. Here is an example script that demonstrates this: #.
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5 min readTo properly assign a null value from a bash script to MySQL, you can use the following method. When inserting data into a MySQL database and you want to assign a null value to a column, you can do so by using the keyword "NULL" (in uppercase) without any quotes.
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5 min readTo modify printf with the last -10 command in bash, you can use the !! shortcut to access the previous command and then pipe the output to printf with the desired format. For example, you can use the following command to print the last -10 command in a specific format: !! | tail -10 | printf "%s\n" This will retrieve the last -10 command from the command history, extract only the last 10 lines using tail, and then print them using printf with the specified format.
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4 min readYou can check for the latest available Python 3.x version from bash by using the command curl to make a request to the official Python website and grep to filter out the latest version number. You can use the following command:curl -s 'https://www.python.org/downloads/' | grep -o -E 'Python [0-9]+\.[0-9]+\.
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4 min readIn Bash, you can check if an argument starts with "--" by using the built-in parameter expansion feature. You can access the value of each argument by referencing it as $1, $2, $3, and so on.
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4 min readTo add decimal values in bash, you can use the bc command. This command allows you to perform calculations with decimal numbers. Here's a simple example of how you can add two decimal values in bash using the bc command:result=$(echo "3.14 + 2.5" | bc) echo $resultIn this example, the echo command is used to provide the calculation "3.14 + 2.5" to the bc command. The bc command then performs the addition and stores the result in the variable result.
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5 min readTo get the value from a text file for a particular string in bash, you can use the grep command along with some text processing commands like awk or cut.Here's a simple example: value=$(grep "search_string" file.txt | awk '{print $2}') echo $value In this example, we are searching for the "search_string" in the file.txt and then using awk to extract the value associated with that string (assuming it's in the second column).
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4 min readTo set grid layout gravity using Kotlin, you can use the GridLayout.LayoutParams class to specify the gravity for each cell in the grid layout. You can create a new instance of GridLayout.LayoutParams and set the gravity using the setGravity method with the desired Gravity constant as the parameter. For example, to set the gravity of a view in the grid layout to Gravity.CENTER, you can do the following: val params = GridLayout.LayoutParams() params.setGravity(Gravity.CENTER) view.
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4 min readTo export D3.js visualizations to an image or PDF, you can use the html2canvas library in combination with jsPDF. First, use html2canvas to capture the HTML elements containing the D3.js visualization and convert them to a canvas element. Then, pass this canvas element to jsPDF to generate a PDF document or convert it to an image by using the toDataURL method. This approach allows you to save your D3.