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All questions must be answered. Here are the Answers given by this user in the Forum.

Lists

Python lists are very flexible and can hold arbitrary data.

Lists are a part of Python’s syntax, so they do not need to be declared first.

Arrays

Python arrays are just a thin wrapper on C arrays.

Arrays need to first be imported, or declared, from other libraries (i.e. numpy).
3 years ago
This error happens on your side and NOT the other side. If the other side reset the connection, then the exception message should say:
***
java.net.SocketException reset by peer
***
The cause is the connection inside HttpClient is stale. Check stale connection for SSL does not fix this error. Solution: dump your client and recreate.
3 years ago
***
my.data.frame <- subset(data , V1 > 2 | V2 < 4)
***
An alternative solution that mimics the behavior of this function and would be more appropriate for inclusion within a function body:
***
new.data <- data[ which( data$V1 > 2 | data$V2 < 4) , ]
***
Some people criticize the use of which as not needed, but it does prevent the NA values from throwing back unwanted results. The equivalent (.i.e not returning NA-rows for any NA's in V1 or V2) to the two options demonstrated above without the which would be:
***
new.data <- data[ !is.na(data$V1 | data$V2) & ( data$V1 > 2 | data$V2 < 4) , ]
***
Note: I want to thank the anonymous contributor that attempted to fix the error in the code immediately above, a fix that got rejected by the moderators. There was actually an additional error that I noticed when I was correcting the first one. The conditional clause that checks for NA values needs to be first if it is to be handled as I intended, since ...
***
> NA & 1
[1] NA
> 0 & NA
[1] FALSE
***
Order of arguments may matter when using '&".
3 years ago
***
as.data.frame.matrix(mytable)
***
does what I need -- apparently, the table needs to somehow be converted to a matrix in order to be appropriately translated into a data frame.
3 years ago
This doesn't answer your question directly, but it will give you the elements that are in common. This can be done with Paul Murrell's package compare:
***
library(compare)
a1 <- data.frame(a = 1:5, b = letters[1:5])
a2 <- data.frame(a = 1:3, b = letters[1:3])
comparison <- compare(a1,a2,allowAll=TRUE)
comparison$tM
# a b
#1 1 a
#2 2 b
#3 3 c
***
The function compare gives you a lot of flexibility in terms of what kind of comparisons are allowed (e.g. changing order of elements of each vector, changing order and names of variables, shortening variables, changing case of strings). From this, you should be able to figure out what was missing from one or the other. For example (this is not very elegant):
***
difference <-
data.frame(lapply(1:ncol(a1),function(i)setdiff(a1[,i],comparison$tM[,i])))
colnames(difference) <- colnames(a1)
difference
# a b
#1 4 d
#2 5 e
***
3 years ago
There are numerous approaches to achieve data partitioning. For a more complete approach take a look at the createDataPartition function in the caTools package.

Here is a simple example:
***
data(mtcars)

## 75% of the sample size
smp_size <- floor(0.75 * nrow(mtcars))

## set the seed to make your partition reproducible
set.seed(123)
train_ind <- sample(seq_len(nrow(mtcars)), size = smp_size)

train <- mtcars[train_ind, ]
test <- mtcars[-train_ind, ]
***
3 years ago
that because you calling toggle inside the render method which will cause to re-render and toggle will call again and re-rendering again and so on

this line at your code
***
{Details}
***
you need to make onClick refer to this.toggle not calling it

to fix the issue do this
***
{Details}
***
3 years ago
To help you get the desired outcome in perhaps a different way than you asked:
***
render: function() {
...

...
},
removeTag: function(i) {
// do whatever
},
***
Notice the bind(). Because this is all javascript, you can do handy things like that. We no longer need to attach data to DOM nodes in order to keep track of them.

IMO this is much cleaner than relying on DOM events.
3 years ago
***
componentDidMount() {
window.scrollTo(0, 0)
}
***
React v16.8+
***
useEffect(() => {
window.scrollTo(0, 0)
}, [])
***
3 years ago
Using Hooks (React 16.8.0+)

Create a useWindowDimensions hook.
***
import { useState, useEffect } from 'react';

function getWindowDimensions() {
const { innerWidth: width, innerHeight: height } = window;
return {
width,
height
};
}

export default function useWindowDimensions() {
const [windowDimensions, setWindowDimensions] = useState(getWindowDimensions());

useEffect(() => {
function handleResize() {
setWindowDimensions(getWindowDimensions());
}

window.addEventListener('resize', handleResize);
return () => window.removeEventListener('resize', handleResize);
}, []);

return windowDimensions;
}
***
And after that you'll be able to use it in your components like this
***
const Component = () => {
const { height, width } = useWindowDimensions();

return (

width: {width} ~ height: {height}

);
}
***
3 years ago
***
$( '#formId' )
.submit( function( e ) {
$.ajax( {
url: 'FormSubmitUrl',
type: 'POST',
data: new FormData( this ),
processData: false,
contentType: false
} );
e.preventDefault();
} );
***
3 years ago
From what I understand, your question is not really about whether to use jQuery or not. It's rather: Is it better to bind events inline in HTML or through event listeners?

Inline binding is deprecated. Moreover this way you can only bind one function to a certain event.

Therefore I recommend using event listeners. This way, you'll be able to bind many functions to a single event and to unbind them later if needed. Consider this pure JavaScript code:
***
querySelector('#myDiv').addEventListener('click', function () {
// Some code...
});
***
This works in most modern browsers.

However, if you already include jQuery in your project — just use jQuery: .on or .click function.
3 years ago