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Selecting multiple columns in a pandas dataframe
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The column names (which are strings) cannot be sliced in the manner you tried.
Here you have a couple of options. If you know from context which variables you want to slice out, you can just return a view of only those columns by passing a list into the...
CSS: center element within a element
... text-align:center;
background-color:blue;
height:400px;
width:600px;
}
.block {
height:100px;
width:200px;
text-align:left;
}
.center {
margin:auto;
background-color:green;
}
.left {
margin:auto auto auto 0;
background-color:red;
}
.right ...
Regex: ignore case sensitivity
...ld look for the i flag. Nearly all regex engines support it:
/G[a-b].*/i
string.match("G[a-b].*", "i")
Check the documentation for your language/platform/tool to find how the matching modes are specified.
If you want only part of the regex to be case insensitive (as my original answer presumed)...
View's SELECT contains a subquery in the FROM clause
...
create view view_clients_credit_usage as
select client_id, sum(credits_used) as credits_used
from credit_usage
group by client_id
create view view_credit_status as
select
credit_orders.client_id,
sum(credit_orders.number_of_credits) as purchased,...
Does Dart support enumerations?
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how about this approach:
class FruitEnums {
static const String Apple = "Apple";
static const String Banana = "Banana";
}
class EnumUsageExample {
void DoSomething(){
var fruit = FruitEnums.Apple;
String message;
switch(fruit){
case(FruitEnums.Apple):
...
Android: Force EditText to remove focus? [duplicate]
...ocus from the EditText. For example if the Keyboard appears, and the user hides it with the back button, I would like the focus and the cursor to disappear. How can it be done?
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jquery how to empty input field
...nput type="number" min="0' max="10" value="5"></input>? I guess said differently, are you allowed to set a numeric input to be blank?
– Kevin Wheeler
Jun 10 '15 at 21:49
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MongoDB - Update objects in a document's array (nested updating)
...o use the positional "$" operator. Something like:
db.bar.update( {user_id : 123456 , "items.item_name" : "my_item_two" } ,
{$inc : {"items.$.price" : 1} } ,
false ,
true);
Note that this will only increment the first matched subdocument in any...
Coalesce function for PHP?
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Putting func_get_args() inside the foreach (here as $arg) won't change anything from a performance point of view.
– Savageman
Dec 12 '09 at 1:47
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Detect when an HTML5 video finishes
How do you detect when a HTML5 <video> element has finished playing?
7 Answers
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