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Combine two columns of text in pandas dataframe
...
if both columns are strings, you can concatenate them directly:
df["period"] = df["Year"] + df["quarter"]
If one (or both) of the columns are not string typed, you should convert it (them) first,
df["period"] = df["Year"].astype(str) + df["quarter"]
Beware...
Read file line by line using ifstream in C++
...d "token" you meant "delimiter". Right. With a comma, you'd say: int a, b; char c; while ((infile >> a >> c >> b) && (c == ','))
– Kerrek SB
Oct 18 '14 at 15:25
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Undefined, unspecified and implementation-defined behavior
...t's look at a classic example:
#include <iostream>
int main()
{
char* p = "hello!\n"; // yes I know, deprecated conversion
p[0] = 'y';
p[5] = 'w';
std::cout << p;
}
The variable p points to the string literal "hello!\n", and the two assignments below try to modify tha...
Adding a newline into a string in C#
...fkdfdsfdflkdkfk@ dfsdfjk72388389@ kdkfkdfkkl@ jkdjkfjd@ jjjk@ The New line character is not effective in the text file.
– balaweblog
Oct 22 '08 at 4:08
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How to import CSV file data into a PostgreSQL table?
...lution paraphrased here:
Create your table:
CREATE TABLE zip_codes
(ZIP char(5), LATITUDE double precision, LONGITUDE double precision,
CITY varchar, STATE char(2), COUNTY varchar, ZIP_CLASS varchar);
Copy data from your CSV file to the table:
COPY zip_codes FROM '/path/to/csv/ZIP_CODES.txt' ...
In VIM, how do I break one really long line into multiple lines?
Say I have a super long line in the VIM editor (say around 300+ characters). How would I break that up into multiple lines so that the word boundaries roughly break at 80 characters?
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What is the difference between const int*, const int * const, and int const *?
...ften this is seen with C-style strings where you have a pointer to a const char. You may change which string you point to but you can't change the content of these strings. This is important when the string itself is in the data segment of a program and shouldn't be changed.
bar is a constant or fi...
How can I get selector from jQuery object
...rn this.tagName; })
.get()
.reverse()
.concat([this.nodeName])
.join(">");
var id = $(this).attr("id");
if (id) {
selector += "#"+ id;
}
var classNames = $(this).attr("class");
if (cla...
Bitwise operation and usage
...(where n is the bit number, and 0 is the least significant bit):
unsigned char a |= (1 << n);
Clear a bit:
unsigned char b &= ~(1 << n);
Toggle a bit:
unsigned char c ^= (1 << n);
Test a bit:
unsigned char e = d & (1 << n);
Take the case of your list for exampl...
Concatenate strings in Less
...e it was changing my background-image url, and I wasn't too sure how to do concatenation :)
– hatsrumandcode
Dec 22 '15 at 16:18
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