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How can I format a decimal to always show 2 decimal places?

...y, wrapping num in a tuple is a coding convention to prevent a duck typing error on arguments during string formatting. It doesn't have any effect in this case with a float conversion, but it prevents an unexpected type error when converting to strings. Consider r = 1; "%s" % r; r = (1, 2); "%s" %...
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How to drop columns using Rails migration

...table_name, :column_name, :column_type. Otherwise you'll get the following error when trying to run the migration: remove_column is only reversible if given a type – Dennis Mar 26 '14 at 13:35 ...
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App Inventor 2 UrsPahoMqttClient 拓展 - 物联网轻量级MQTT协议 · App Inventor 2 中文网

... 由于错误或中断,无法建立连接。可以通过属性 LastErrorCode 和 LastErrorMessage 查看错误原因。 Connect 常量属性: 为了简化状态查询,已经实现了 IsConnected 和 IsDisconnected 属性: 下面的状态图解释了连接建立和...
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How do I get Flask to run on port 80?

... So it's throwing up that error message because you have apache2 running on port 80. If this is for development, I would just leave it as it is on port 5000. If it's for production either: Not Recommended Stop apache2 first; Not recommended as...
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Android Crop Center of Bitmap

... targeted width height targeted height I was getting out of memory errors sometimes when using the accepted answer, and using ThumbnailUtils resolved those issues for me. Plus, this is much cleaner and more reusable. ...
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typedef struct vs struct definitions [duplicate]

... are different, defining S both in the structs and global spaces is not an error, as it is not redefining the same identifier, but rather creating a different identifier in a different place. To make the difference clearer: typedef struct S { int x; } T; void S() { } // correct //void T() ...
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Is is possible to check if an object is already attached to a data context in Entity Framework?

I am getting the following error when trying to attach an object that is already attached to a given context via context.AttachTo(...) : ...
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How do you debug MySQL stored procedures?

...oesn't seem to work for FUNCTIONS and I have no idea why. It always gives "Error Code: 1415. Not allowed to return a result set from a function". Is there any recourse? – Patrick M Jul 28 '15 at 21:29 ...
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Get Insert Statement for existing row in MySQL

... See this if you get the error mysqldump: Couldn't execute 'SELECT @@GTID_MODE': Unknown system variable 'GTID_MODE' (1193) gist.github.com/arun057/5556563 – Daniel Schaffer Jul 12 '13 at 22:39 ...
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Python - 'ascii' codec can't decode byte

I'm really confused. I tried to encode but the error said can't decode... . 7 Answers ...