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How to create PDF files in Python [closed]
...ich takes some images from user and then creates a PDF file which contains all of these images.
14 Answers
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Drop multiple tables in one shot in mysql
...e A has two children B and C. Then we can use the following syntax to drop all tables.
DROP TABLE IF EXISTS B,C,A;
This can be placed in the beginning of the script instead of individually dropping each table.
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How to print a dictionary line by line in Python?
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Hmm. I think my problem is even worse than that. Basically I've parsed out some data from an HTML table, and I happened to store it in a dictionary, and now I'm trying to take that dictionary data and put it into a DataFrame before I export it all to an Oracle table....it's pret...
How to get a random number in Ruby
...6). A roll in craps could be simulated with 2 + rand(6) + rand(6).
Finally, if you just need a random float, just call rand with no arguments.
As Marc-André Lafortune mentions in his answer below (go upvote it), Ruby 1.9.2 has its own Random class (that Marc-André himself helped to debug,...
Checking for empty queryset in Django
...if not my_objects: to demonstrate that this is how they do it in the docs. All else is utterly irrelevant so I do not get your point. They could as well make a thousand queries and it would still be totally irrelevant as this is not the point of this answer, with which I make clear that I agree.
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Does .NET have a way to check if List a contains all items in List b?
...s easy:
public class ListHelper<T>
{
public static bool ContainsAllItems(List<T> a, List<T> b)
{
return !b.Except(a).Any();
}
}
This checks whether there are any elements in b which aren't in a - and then inverts the result.
Note that it would be slightly mo...
SQL to determine minimum sequential days of access?
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@Artem: That was what I initially thought but when I thought about it, if you have an index on (UserId, CreationDate), the records will show up consecutively in the index and it should perform well.
– Mehrdad Afshari
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Convert .pem to .crt and .key
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Converting Using OpenSSL
These commands allow you to convert certificates and keys to different formats to make them compatible with specific types of servers or software.
Convert a DER file (.crt .cer .der) to PEM
openssl x509 -inform der -in certificate.cer -o...
How to turn on/off ReactJS 'development mode'?
...me helpers off during production. Just using the minified react will leave all those potential optimizations on the table as well.
Ultimately the magic comes down to React embedding references to process.env.NODE_ENV throughout the codebase; these act like a feature toggle.
if (process.env.NODE_ENV ...
64 bit OS下int占几个字节？ - C/C++ - 清泛网 - 专注C/C++及内核技术
...混淆。int是由编程语言设计决定的，不受编译器的影响。__int64才是8位的。另外，指针是受编译器 OS影响的，3...int固定4字节，不要受64 bit的混淆。int是由编程语言设计决定的，不受编译器的影响。
__int64才是8位的。
另外，指...