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How can I convert an RGB image into grayscale in Python?
I'm trying to use matplotlib to read in an RGB image and convert it to grayscale.
12 Answers
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How to properly import a selfsigned certificate into Java keystore that is available to all Java app
I do want to import a self signed certificate into Java so any Java application that will try to establish a SSL connection will trust this certificate.
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MySQL, better to insert NULL or empty string?
I have a form on a website which has a lot of different fields. Some of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
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What do the makefile symbols $@ and $< mean?
What do the $@ and $< do exactly?
6 Answers
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What is the Oracle equivalent of SQL Server's IsNull() function?
In SQL Server we can type IsNull() to determine if a field is null. Is there an equivalent function in PL/SQL?
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Convert SQLITE SQL dump file to POSTGRESQL
I've been doing development using SQLITE database with production in POSTGRESQL. I just updated my local database with a huge amount of data and need to transfer a specific table to the production database.
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jquery-ui sortable | How to get it work on iPad/touchdevices?
How do I get the jQuery-UI sortable feature working on iPad and other touch devices?
3 Answers
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How to write multiple line property value using PropertiesConfiguration?
I have a properties file with a property with a List value (comma separated), how to write this property in a multi-line ? (backslash after the comma)?
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How many characters can UTF-8 encode?
If UTF-8 is 8 bits, does it not mean that there can be only maximum of 256 different characters?
10 Answers
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Do AJAX requests retain PHP Session info?
If I had a user logged onto my site, having his id stored in $_SESSION , and from his browser he clicked a 'Save' button which would make an AJAX request to the server. Will his $_SESSION and cookies be retained in this request, and can I safely rely on the id being present in the $_SESSION ?
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