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pyplot scatter plot marker size
... size but you are basically specifying the area of the marker. This means, to double the width (or height) of the marker you need to increase s by a factor of 4. [because A = WH => (2W)(2H)=4A]
There is a reason, however, that the size of markers is defined in this way. Because of the scaling o...
How to get ID of the last updated row in MySQL?
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I've found an answer to this problem :)
SET @update_id := 0;
UPDATE some_table SET column_name = 'value', id = (SELECT @update_id := id)
WHERE some_other_column = 'blah' LIMIT 1;
SELECT @update_id;
EDIT by aefxx
This technique can be further...
Undo a Git merge that hasn't been pushed yet
... did a git merge some-other-branch locally, but never pushed the changes to origin master. I didn't mean to merge, so I'd like to undo it. When doing a git status after my merge, I was getting this message:
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When should I use malloc in C and when don't I?
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char *some_memory = "Hello World";
is creating a pointer to a string constant. That means the string "Hello World" will be somewhere in the read-only part of the memory and you just have a pointer to it. You can use the string as read-only. You cannot make changes to it. Example:
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Convert Java Array to Iterable
...r
Iterable<Integer> iterable = Arrays.asList(foo);
Though you need to use an Integer array (not an int array) for this to work.
For primitives, you can use guava:
Iterable<Integer> fooBar = Ints.asList(foo);
<dependency>
<groupId>com.google.guava</groupId>
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When to use symbols instead of strings in Ruby?
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TL;DR
A simple rule of thumb is to use symbols every time you need internal identifiers. For Ruby < 2.2 only use symbols when they aren't generated dynamically, to avoid memory leaks.
Full answer
The only reason not to use them for identifiers that are...
Plotting two variables as lines using ggplot2 on the same graph
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nice example, but how to customize my own colours (E.g. black and orange)?, because it seems that you are using colour= as the variable name.
– Darwin PC
Oct 27 '15 at 14:23
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How to update a single library with Composer?
I need to install only 1 package for my SF2 distribution (DoctrineFixtures).
8 Answers
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Is it expensive to use try-catch blocks even if an exception is never thrown?
We know that it is expensive to catch exceptions. But, is it also expensive to use a try-catch block in Java even if an exception is never thrown?
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How to force JS to do math instead of putting two strings together
I need javascript to add 5 to an integer variable, but instead it treats the variable as a string, so it write out the variable, then add 5 onto the end of the "string". How can I force it to do math instead?
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