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Check if value already exists within list of dictionaries?
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Here's one way to do it:
if not any(d['main_color'] == 'red' for d in a):
# does not exist
The part in parentheses is a generator expression that returns True for each dictionary that has the key-value pair you are looking for, otherwise False.
If the key coul...
Does the ternary operator exist in R?
As the question asks, is there a control sequence in R similar to C's ternary operator ? If so, how do you use it? Thanks!
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How can one print a size_t variable portably using the printf family?
I have a variable of type size_t , and I want to print it using printf() . What format specifier do I use to print it portably?
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In C++, if throw is an expression, what is its type?
I picked this up in one of my brief forays to reddit:
4 Answers
4
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The role of #ifdef and #ifndef
In this what is the role of #ifdef and #ifndef , and what's the output?
4 Answers
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WebException how to get whole response with a body?
In WebException I cannot see body of GetResponse. This is my code in C#:
3 Answers
3
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Plotting a list of (x, y) coordinates in python matplotlib
... have a list of pairs (a, b) that I would like to plot with matplotlib in python as actual x-y coordinates. Currently, it is making two plots, where the index of the list gives the x-coordinate, and the first plot's y values are the a s in the pairs and the second plot's y values are the b s i...
Filter output in logcat by tagname
I'm trying to filter logcat output from a real device (not an emulator) by tag name but I get all the messages which is quite a spam. I just want to read messages from browser which should be something like "browser: " or "webkit: " , but it doesn't work...
Here it is what I get:
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What is the meaning of git reset --hard origin/master?
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git reset --hard origin/master
says: throw away all my staged and unstaged changes, forget everything on my current local branch and make it exactly the same as origin/master.
You probably wanted to ask this before you ran the command. The des...
What's a standard way to do a no-op in python?
I often find myself writing if / elif / else constructs in python, and I want to include options which can occur, but for which the corresponding action is to do nothing. I realise I could just exclude those if statements, but for readability I find it helps to include them all, so that if you are l...