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Adding new column to existing DataFrame in Python pandas
...a new object (a copy) with all the original columns in addition to the new ones.
df1 = df1.assign(e=e.values)
As per this example (which also includes the source code of the assign function), you can also include more than one column:
df = pd.DataFrame({'a': [1, 2], 'b': [3, 4]})
>>> df...
Rotating x axis labels in R for barplot
...you'll probably want to use colMeans(x) instead of just x if you want only one label per group.
– MichaelChirico
Oct 7 '16 at 3:59
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How to write trycatch in R
...h(
{
# Just to highlight: if you want to use more than one
# R expression in the "try" part then you'll have to
# use curly brackets.
# 'tryCatch()' will return the last evaluated expression
# in case the "try" part was completed...
NullPointerException accessing views in onCreate()
... {
void exampleFragmentCallback();
}
private Button btnOne;
private Button btnTwo;
private Button btnThree;
private Callback callback;
@Override
public void onAttach(Activity activity)
{
super.onAttach(activity);
try
{
...
Print function log /stack trace for entire program using firebug
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Try stepping through your code one line or one function at a time to determine where it stops working correctly. Or make some reasonable guesses and scatter logging statements through your code.
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difference between foldLeft and reduceLeft in Scala
... returned backwards, because we used foldLeft instead of foldRight.
Watch One Fold to rule them all for a more in depth explanation.
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Get an array of list element contents in jQuery
... ways to do the same thing (you could use $.map() to generate the array in one go), but they amount to the same thing.
– Shog9
Nov 1 '13 at 16:01
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How does Duff's device work?
... at the do so much. Instead, look at the switch and the while as old-fashioned computed GOTO statments or assembler jmp statements with an offset. The switch does some math and then jmps to the right place. The while does a boolean check and then blindly jmps to right about where the do was.
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How to search a Git repository by commit message?
... your history, check the reflog as your safety net. Look for Build 0051 in one of the commits listed by
git reflog
You may have simply set your HEAD to a part of history in which the 'Build 0051' commit is not visible, or you may have actually blown it away. The git-ready reflog article may be o...
List all the files that ever existed in a Git repository
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In one of my repos, I get quite a few duplicate lines (including a number of blank lines at the beginning of the output) with the second command that aren't dupes with the first.
– Slipp D. Thompson
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