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Converting an array of objects to ActiveRecord::Relation
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How can I convert an Array of objects to an ActiveRecord::Relation? Preferably without doing a where each time.
You cannot convert an Array to an ActiveRecord::Relation since a Relation is just a builder for a SQL query and its metho...
How to step through Python code to help debug issues?
... and call pdb.set_trace(). However, you can control debugging behavior via sys.breakpointhook() and use of the environment variable PYTHONBREAKPOINT.
See PEP 553 for more information.
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WPF: Setting the Width (and Height) as a Percentage Value
... I already tried that, but I'm getting this error: '2*' string cannot be converted to Length.'
– Andreas Grech
Apr 4 '09 at 16:06
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How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
...ways have to look at the context to see what, where and why something gets converted to understand what is going on.
Converting rules
Converting to boolean
Converting to integer
Converting to float
Converting to string
Converting to array
Converting to object
Converting to resource
Converting to ...
Converting an object to a string
How can I convert a JavaScript object into a string?
36 Answers
36
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Convert column classes in data.table
I have a problem using data.table: How do I convert column classes? Here is a simple example: With data.frame I don't have a problem converting it, with data.table I just don't know how:
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App Inventor 2 数学代码块 · App Inventor 2 中文网
...(acos)
反正切 (atan)
反正切2 (atan2)
将弧度转换为度数 (convert radians to degrees)
将度数转换为弧度 (convert degrees to radians)
数字转变为小数形式 (format as a decimal)
是否为数字 (is a number)
进制转换 (convert number)
按位与 (bitwise and)...
Convert a list to a data frame
...gth is 132 and each item is a list of length 20. Is there a quick way to convert this structure into a data frame that has 132 rows and 20 columns of data?
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How to secure database passwords in PHP?
... Then leave administration and securing that configuration file up to your system administrators. That way developers do not need to know anything about the production passwords, and there is no record of the password in your source-control.
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How do I check if a string is a number (float)?
...want is_number to return FALSE for 'NaN' this code will not work as Python converts it to its representation of a number that is not a number (talk about identity issues):
>>> float('NaN')
nan
Otherwise, I should actually thank you for the piece of code I now use extensively. :)
G.
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