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Replacing Pandas or Numpy Nan with a None to use with MysqlDB
... out an error saying nan is not in the field list. I need to find a way to convert the 'nan' into a NoneType.
7 Answers
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Parse v. TryParse
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If the string can not be converted to an integer, then
int.Parse() will throw an exception
int.TryParse() will return false (but not throw an exception)
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Downloading a Google font and setting up an offline site that uses it
...u downloaded (.ttf should be extracted)
Go to "http://ttf2woff.com/" and convert any .ttf extracted from zip to .woff
Edit desiredfontname.css and replace any url within it [between 'url(' and ')'] with the corresponding converted .woff file you got on ttf2woff.com; path you write should be acco...
Deserialize json object into dynamic object using Json.net
...est]
public void DynamicDeserialization()
{
dynamic jsonResponse = JsonConvert.DeserializeObject("{\"message\":\"Hi\"}");
jsonResponse.Works = true;
Console.WriteLine(jsonResponse.message); // Hi
Console.WriteLine(jsonResponse.Works); // True
Console.WriteLine(JsonConvert.Seriali...
Difference between Covariance & Contra-variance
...nk about the logical reasons that underly these relationships. Why can we convert IEnumerable<Tiger> to IEnumerable<Animal> safely? Because there is no way to input a giraffe into IEnumerable<Animal>. Why can we convert an IComparable<Animal> to IComparable<Tiger>? ...
SQL “between” not inclusive
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@scottb Personally, I would find it annoying to have to convert to datetimes every single time I wanted to display, export, import, or write a class with a datetime. I think SQL Server has plenty of built-in functionality to manipulate and compare datetimes for most purposes.
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Best way to work with dates in Android SQLite [closed]
... date column.
Retrieving dates as strings from SQLite you can then format/convert them as required into local regionalised formats using the Calendar or the android.text.format.DateUtils.formatDateTime method.
Here's a regionalised formatter method I use;
public static String formatDateTime(Conte...
sqlite database default time value 'now'
... the timestamp (created_at-column) is saved as unix epoch UTC timezone and converted to local timezone only when necessary.
Using unix epoch saves storage space - 4 bytes integer vs. 24 bytes string when stored as ISO8601 string, see datatypes. If 4 bytes is not enough that can be increased to 6 or...
What is the !! (not not) operator in JavaScript?
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Converts Object to boolean. If it was falsey (e.g. 0, null, undefined, etc.), it will be false, otherwise, true.
!oObject // inverted boolean
!!oObject // non inverted boolean so true boolean representation
So !! is not a...
Graphviz: How to go from .dot to a graph?
...dot file, which is valid according to the syntax. How do I use graphviz to convert this into an image?
11 Answers
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