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Getting and removing the first character of a string
...ht back" "r" "ight back"
[[3]]
[1] "at yah" "a" "t yah"
Now, we can use the trusty sapply + [ method to pull out the desired substrings.
myFirstStrings <- sapply(myStrings, "[", 2)
myFirstStrings
[1] "h" "r" "a"
mySecondStrings <- sapply(myStrings, "[", 3)
mySecondStrings
[...
Why are empty catch blocks a bad idea? [closed]
...ng to do, but often it's a sign that a developer saw an exception, didn't know what to do about it, and so used an empty catch to silence the problem.
It's the programming equivalent of putting black tape over an engine warning light.
I believe that how you deal with exceptions depends on what l...
Why does one often see “null != variable” instead of “variable != null” in C#?
...is in C by doing:
if (5 == x)
A typo here will result in invalid code.
Now, in C# this is all piffle. Unless you're comparing two Boolean values (which is rare, IME) you can write the more readable code, as an "if" statement requires a Boolean expression to start with, and the type of "x=5" is I...
Convert JSON String to Pretty Print JSON output using Jackson
...e updated the question, maybe you will get some more idea what's happening now.
– arsenal
Jan 26 '13 at 3:09
The probl...
What is the lifetime of a static variable in a C++ function?
...]
[2] In C++11 statics are initialized in a thread safe way, this is also known as Magic Statics.
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Scatter plot and Color mapping in Python
...here is a reference page of colormaps showing what each looks like. Also know that you can reverse a colormap by simply calling it as cmap_name_r. So either
plt.scatter(x, y, c=t, cmap=cm.cmap_name_r)
# or
plt.scatter(x, y, c=t, cmap="cmap_name_r")
will work. Examples are "jet_r" or cm.plasma_...
What is the point of function pointers?
...couple of void pointers to sortable data and a pointer to a function that knows how to compare two elements of these data structures. This allows us to create our function of choice for the job, and in fact even allows for choosing the comparison function at run time, e.g. for sorting ascending or d...
Populating a database in a Laravel migration file
...
I know this is an old post but since it comes up in a google search I thought I'd share some knowledge here. @erin-geyer pointed out that mixing migrations and seeders can create headaches and @justamartin countered that sometim...
Batch renaming files with Bash
.../rename pattern which includes new folder structure.
This will ensure we know the names of our target folders. When we
rename we'll need to use it on the target file name.
# generate the rename target
target="$(sed $sed_pattern <<< $file)"
# Use absolute path of the rename target to mak...
AttributeError: 'module' object has no attribute 'tests'
...ews.py) was still trying to import the deleted model.
When I took out the now-obsolete import statement, problem solved.
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