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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not initialized.
From PHP documentation:
No warning is generated if the variable does not exist. T...
How to create PDF files in Python [closed]
...ich takes some images from user and then creates a PDF file which contains all of these images.
14 Answers
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Concatenate text files with Windows command line, dropping leading lines
...is via the command line. Unfortunately I only have Windows, and cannot install new software.
12 Answers
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How do you turn a Mongoose document into a plain object?
...ng is that JSON.parse(JSON.encode(doc)) works and returns an object with all of the correct properties. Is there a better way to do this?
...
The purpose of Model View Projection Matrix
...d space to camera space, projection from camera to screen.
If you compose all three, you can use the one result to map all the way from object space to screen space, making you able to work out what you need to pass on to the next stage of a programmable pipeline from the incoming vertex positions....
Assembly code vs Machine code vs Object code?
...e to machine code with the use of an assembler or a compiler, though we usually think of compilers in association with high-level programming language that are abstracted further from the CPU instructions.
Building a complete program involves writing source code for the program in either assembly or...
How Python web frameworks, WSGI and CGI fit together
...
How WSGI, CGI, and the frameworks are all connected?
Apache listens on port 80. It gets an HTTP request. It parses the request to find a way to respond. Apache has a LOT of choices for responding. One way to respond is to use CGI to run a script. Another w...
moving committed (but not pushed) changes to a new branch after pull
...of work ("Your branch is ahead of 'origin/master' by 37 commits.") which really should have gone into its own branch rather than into master . These commits only exist on my local machine and have not been pushed to origin , but the situation is complicated somewhat in that other devs have been p...
What's the rationale for null terminated strings?
... by a
special character, which B spelled
*e. This change was made partially
to avoid the limitation on the length
of a string caused by holding the
count in an 8- or 9-bit slot, and
partly because maintaining the count
seemed, in our experience, less
convenient than using a terminato...