大约有 13,330 项符合查询结果（耗时：0.0387秒） [XML]
Convert unix time to readable date in pandas dataframe
...12.15
3 1349979305 12.19
4 1350065705 12.15
In [25]: df['date'] = pd.to_datetime(df['date'],unit='s')
In [26]: df.head()
Out[26]:
date price
0 2012-10-08 18:15:05 12.08
1 2012-10-09 18:15:05 12.35
2 2012-10-10 18:15:05 12.15
3 2012-10-11 18:15:05 12.19
4 2012-10-12 18:15:...
Linux: copy and create destination dir if it does not exist
...he info page (viewable at http://www.gnu.org/software/coreutils/manual/html_node/cp-invocation.html#cp-invocation or with info cp or man cp):
--parents
Form the name of each destination file by appending to the target
directory a slash and the specified name of the source file. The
...
Extracting text OpenCV
...s(cv::Mat img)
{
std::vector<cv::Rect> boundRect;
cv::Mat img_gray, img_sobel, img_threshold, element;
cvtColor(img, img_gray, CV_BGR2GRAY);
cv::Sobel(img_gray, img_sobel, CV_8U, 1, 0, 3, 1, 0, cv::BORDER_DEFAULT);
cv::threshold(img_sobel, img_threshold, 0, 255, CV_THRESH_O...
Upgrading PHP in XAMPP for Windows?
...e\bin with the newer versions.
Now the trick: take the files which have a '_2' in their names (for example php5apache2_2.dll or php5apache2_2_filter.dll), copy them in the apache\bin subdirectory and remove the '_2' part, overwriting the existing files. This is necessary because by XAMPP uses Apache...
Naming returned columns in Pandas aggregate function? [duplicate]
...l() function on the multi-level column to form new labels:
df.columns = ["_".join(x) for x in df.columns.ravel()]
For example:
import pandas as pd
import pandas.rpy.common as com
import numpy as np
data = com.load_data('Loblolly')
print(data.head())
# height age Seed
# 1 4.51 3 3...
how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...use a query like this: "start transaction; create temporary table temporary_table as select * from test where false; copy temporary_table from 'data_file.csv'; lock table test; update test set data=temporary_table.data from temporary_table where test.id=temporary_table.id; insert into test select * ...
Handling an empty UITableView. Print a friendly message
...xtension:
import UIKit
extension UITableView {
func setEmptyMessage(_ message: String) {
let messageLabel = UILabel(frame: CGRect(x: 0, y: 0, width: self.bounds.size.width, height: self.bounds.size.height))
messageLabel.text = message
messageLabel.textColor = .black
...
Installing PDO driver on MySQL Linux server
...-get install php5-mysql
There is no limitation between using PDO and mysql_ simultaneously. You will however need to create two connections to your DB, one with mysql_ and one using PDO.
share
|
im...
Where can I learn how to write C code to speed up slow R functions? [closed]
...:
SEXP foobar(){
SEXP ab;
PROTECT(ab = allocVector(STRSXP, 2));
SET_STRING_ELT( ab, 0, mkChar("foo") );
SET_STRING_ELT( ab, 1, mkChar("bar") );
UNPROTECT(1);
}
Using Rcpp, you can write the same function as:
SEXP foobar(){
return Rcpp::CharacterVector::create( "foo", "bar" ) ;
}
...
What is the difference between C# and .NET?
...ment 0x00000200
.stackreserve 0x00100000
.subsystem 0x0003 // WINDOWS_CUI
.corflags 0x00000001 // ILONLY
// Image base: 0x05DB0000
// =============== CLASS MEMBERS DECLARATION ===================
.class public auto ansi beforefieldinit Example.Class1
extends [mscorlib]System.Objec...