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Python pandas: fill a dataframe row by row
The simple task of adding a row to a pandas.DataFrame object seems to be hard to accomplish. There are 3 stackoverflow questions relating to this, none of which give a working answer.
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Start an Activity with a parameter
...nt.
Intent intent = new Intent(FirstActivity.this, SecondActivity.class);
Bundle b = new Bundle();
b.putInt("key", 1); //Your id
intent.putExtras(b); //Put your id to your next Intent
startActivity(intent);
finish();
Then grab the id in your new Activity:
Bundle b = getIntent().getExtras();
int ...
Add list to set?
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You can't add a list to a set because lists are mutable, meaning that you can change the contents of the list after adding it to the set.
You can however add tuples to the set, because you cannot change the contents of a tuple:
>>> a.add(('f', ...
Why doesn't a python dict.update() return the object?
...e (with pragmatically induced exceptions such as pop;-) so they can't possibly be confused with accessors (and in the same vein, assignment is not an expression, the statement-expression separation is there, and so forth).
That doesn't mean there aren't a lot of ways to merge things up when you rea...
Implement Stack using Two Queues
A similar question was asked earlier there , but the question here is the reverse of it, using two queues as a stack. The question...
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Cleaning `Inf` values from an R dataframe
...apply(DT, function(x) replace(x, is.infinite(x),NA)))
Option 2 -- data.table
You could use data.table and set. This avoids some internal copying.
DT <- data.table(dat)
invisible(lapply(names(DT),function(.name) set(DT, which(is.infinite(DT[[.name]])), j = .name,value =NA)))
Or using column ...
How can I use an array of function pointers?
...Array of Function pointers), with the syntax detailed.
int sum(int a, int b);
int subtract(int a, int b);
int mul(int a, int b);
int div(int a, int b);
int (*p[4]) (int x, int y);
int main(void)
{
int result;
int i, j, op;
p[0] = sum; /* address of sum() */
p[1] = subtract; /* address of...
Determining complexity for recursive functions (Big O notation)
...complexity of these recursive functions. I know how to solve simple cases, but I am still trying to learn how to solve these harder cases. These were just a few of the example problems that I could not figure out. Any help would be much appreciated and would greatly help in my studies, Thank you! ...
How to do 3 table JOIN in UPDATE query?
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the answer is yes you can
try it like that
UPDATE TABLE_A a
JOIN TABLE_B b ON a.join_col = b.join_col AND a.column_a = b.column_b
JOIN TABLE_C c ON [condition]
SET a.column_c = a.column_c + 1
EDIT:
For general Update join :
UPDATE TABLEA a
JOIN TABLEB b ON...
How can I transform between the two styles of public key format, one “BEGIN RSA PUBLIC KEY”, the oth
How can I transform between the two styles of public key format,
one format is:
5 Answers
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