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python - How to deal with SettingWithCopyWarning in Pandas

Background I just upgraded my Pandas from 0.11 to 0.13.0rc1. Now, the application is popping out many new warnings. One of them ... : x[0:4]+x[5:7]+x[8:10]) Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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How to replace all occurrences of a string in JavaScript

I have this string in my JavaScript code: "Test abc test test abc test test test abc test test abc" Doing: ... above. How can I replace all occurrences of it? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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192 views

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c++ - What are copy elision and return value optimization?

What is copy elision? What is (named) return value optimization? What do they imply? In what situations can ... the standard reference. See common cases here. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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java - What does "Could not find or load main class" mean?

A common problem that new Java developers experience is that their programs fail to run with the error message: Could ... causes it, and how should you fix it? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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jquery - How to use a variable for a key in a JavaScript object literal?

Why does the following work? <something>.stop().animate( { 'top' : 10 }, 10 ); Whereas this doesn't ... a CSS property to the animate function as a variable. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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What Is Selenium And What Is WebDriver?

What is Selenium? When you open the official page of the Selenium, the first thing you read is "Selenium ... two questions in the interview point of view. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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How to compare arrays in JavaScript?

I'd like to compare two arrays... ideally, efficiently. Nothing fancy, just true if they are identical, ... arrays without having to iterate through each value? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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python - How to filter Pandas dataframe using 'in' and 'not in' like in SQL

How can I achieve the equivalents of SQL's IN and NOT IN? I have a list with the required values. Here's ... like a horrible kludge. Can anyone improve on it? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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html - How can I center text (horizontally and vertically) inside a div block?

I have a div set to display:block (90px height and width), and I have some text inside. I need the text to be ... -align:middle, but it didn't work. Any ideas? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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javascript - event.preventDefault() vs. return false

When I want to prevent other event handlers from executing after a certain event is fired, I can use one ... use preventDefault instead? What's the better way? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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157 views

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debugging - Reference - What does this error mean in PHP?

What is this? This is a number of answers about warnings, errors, and notices you might encounter while programming ... - What does this symbol mean in PHP? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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How do you parse and process HTML/XML in PHP?

How can one parse HTML/XML and extract information from it? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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datetime - How to use ThreeTenABP in Android Project

I'm asking this question because I'm new to Java and Android and I searched for hours trying to figure this out. ... Server VM (build 25.91-b14, mixed mode) Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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javascript - Why does jQuery or a DOM method such as getElementById not find the element?

What are the possible reasons for document.getElementById, $("#id") or any other DOM method / jQuery selector ... : Cannot read property 'style' of null Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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javascript - What is the difference between client-side and server-side programming?

I have this code: <script type="text/javascript"> var foo = 'bar'; <?php file_put_contents('foo.txt' ... when you see answers talking about specific languages. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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python - "Least Astonishment" and the Mutable Default Argument

Anyone tinkering with Python long enough has been bitten (or torn to pieces) by the following issue: def ... line is executed, meaning at function definition. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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java - How can I fix 'android.os.NetworkOnMainThreadException'?

I got an error while running my Android project for RssReader. Code: URL url = new URL(urlToRssFeed) ... .NetworkOnMainThreadException How can I fix this issue? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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119 views

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c++ - What are the basic rules and idioms for operator overloading?

Note: The answers were given in a specific order, but since many users sort answers according to votes, rather than ... by those who came up with the idea.) Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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96 views

1 answer

c++ - Can a local variable's memory be accessed outside its scope?

I have the following code. #include <iostream> int * foo() { int a = 5; return &a; } int main ... memory of a local variable inaccessible outside its function? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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174 views

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java - The Use of Multiple JFrames: Good or Bad Practice?

Closed. This question is opinion-based. It is not currently accepting answers. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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297 views

1 answer

swift - What does "Fatal error: Unexpectedly found nil while unwrapping an Optional value" mean?

My Swift program is crashing with EXC_BAD_INSTRUCTION and one of the following similar errors. What does this error ... answer or edit the existing wiki answer. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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205 views

1 answer

html - How do I remove the space between inline/inline-block elements?

Given this HTML and CSS: span { display:inline-block; width:100px; background-color:palevioletred; } <p> <span> Foo </span> <span> Bar </span> </p> Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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c++ - Undefined, unspecified and implementation-defined behavior

What is undefined behavior in C and C++? What about unspecified behavior and implementation-defined behavior? What is the difference between them? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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397 views

1 answer

jquery - Why does my JavaScript code receive a "No 'Access-Control-Allow-Origin' header is present on the requested resource" error, while Postman does not?

Mod note: This question is about why XMLHttpRequest/fetch/etc. on the browser are subject to the Same Access ... (xhr.responseText); alert(textStatus); }); Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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250 views

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html - Why don't flex items shrink past content size?

I have 4 flexbox columns and everything works fine, but when I add some text to a column and set it to a big font ... ="col col4">Lorem ipsum dolor</div> </div> Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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106 views

1 answer

r - Why are these numbers not equal?

The following code is obviously wrong. What's the problem? i <- 0.1 i <- i + 0.05 i ## [1] 0.15 if(i==0.15 ... "i does not equal 0.15") ## i does not equal 0.15 Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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169 views

1 answer

r faq - How to make a great R reproducible example

Question&Answers:os Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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1.1k views

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java - build: Cannot determine build data storage root for project /home/abed/thingsboard

When I build my project, I see this error in IntelliJ IDEA: build: Cannot determine build data storage root ... -determine-build-data-storage-root-for-project-home-abed-thingsboa...

asked Oct 7, 2021 in Technique[技术] by 深蓝 (71.8m points)

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