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What is the correct syntax for 'else if'?
... python "else if" is spelled "elif".
Also, you need a colon after the elif and the else.
Simple answer to a simple question. I had the same problem, when I first started (in the last couple of weeks).
So your code should read:
def function(a):
if a == '1':
print('1a')
elif a == '2...
Summarizing multiple columns with dplyr? [duplicate]
... a bit with the dplyr-syntax. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R.
...
Bash ignoring error for a particular command
...shell to think that the entire pipe has non-zero exit code
when one of commands in the pipe has non-zero exit code (with pipefail off it must the last one).
$ set -o pipefail
$ false | true ; echo $?
1
$ set +o pipefail
$ false | true ; echo $?
0
...
“x not in y” or “not x in y”
...
They always give the same result.
In fact, not 'ham' in 'spam and eggs' appears to be special cased to perform a single "not in" operation, rather than an "in" operation and then negating the result:
>>> import dis
>>> def notin():
'ham' not in 'spam and eggs'
&g...
mysql error 1364 Field doesn't have a default values
...
Set a default value for Created_By (eg: empty VARCHAR) and the trigger will update the value anyways.
create table try (
name varchar(8),
CREATED_BY varchar(40) DEFAULT '' not null
);
share
...
Explain the encapsulated anonymous function syntax
...
It doesn't work because it is being parsed as a FunctionDeclaration, and the name identifier of function declarations is mandatory.
When you surround it with parentheses it is evaluated as a FunctionExpression, and function expressions can be named or not.
The grammar of a FunctionDeclaratio...
MySQL Error 1215: Cannot add foreign key constraint
...
I'm guessing that Clients.Case_Number and/or Staff.Emp_ID are not exactly the same data type as Clients_has_Staff.Clients_Case_Number and Clients_has_Staff.Staff_Emp_ID.
Perhaps the columns in the parent tables are INT UNSIGNED?
They need to be exactly the same...
MySQL INNER JOIN select only one row from second table
I have a users table and a payments table, for each user, those of which have payments, may have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL sta...
How do I break a string over multiple lines?
... edited May 30 '19 at 22:23
Alexander Mills
1
answered Sep 24 '10 at 19:54
Matt WilliamsonMatt Williamson
...
Return multiple columns from pandas apply()
I have a pandas DataFrame, df_test . It contains a column 'size' which represents size in bytes. I've calculated KB, MB, and GB using the following code:
...