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FirstOrDefault: Default value other than null
...p6 = list.FirstOrDefault()?.Bar;
}
For C# 6.0 or later:
Use ?. or ?[ to test if is null before perform a member access Null-conditional Operators documentation
Example:
var barCSharp6 = list.FirstOrDefault()?.Bar;
C# older version:
Use DefaultIfEmpty() to retrieve a default value if the sequen...
Scala: write string to file in one statement
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@Kakaji, could you please elaborate? I've just tested it with strings with newlines, and it works perfectly. It just cannot filter anything - Files.write() writes the byte array as a blob, without analyzing its contents. After all, in some binary data 0x0d byte may have i...
Android: ProgressDialog.show() crashes with getApplicationContext
...'s definitely weird and it's a total hack, but it worked for me. I need to test the bug I was having in 1.6 to see if I can STOP using this.
– Jeremy Logan
Oct 16 '09 at 23:53
1
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What's the best way to determine the location of the current PowerShell script?
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Just tested $PSScriptRoot and working as expected. However, it would give you an empty string if you run it at command line. It would only give you result if used in a script and script is executed. That's what it is meant for ......
How can I set the default timezone in node.js?
...an set the TZ environment variable before calling any date functions. Just tested it and it works.
> process.env.TZ = 'Europe/Amsterdam'
'Europe/Amsterdam'
> d = new Date()
Sat, 24 Mar 2012 05:50:39 GMT
> d.toLocaleTimeString()
'06:50:39'
> ""+d
'Sat Mar 24 2012 06:50:39 GMT+0100 (CET)...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
...problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try different parameters within each algorithm as well), and select the best one by cross-validation. But if you’re simply looking for a “good enough” algorithm for y...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
...problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try different parameters within each algorithm as well), and select the best one by cross-validation. But if you’re simply looking for a “good enough” algorithm for y...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
...problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try different parameters within each algorithm as well), and select the best one by cross-validation. But if you’re simply looking for a “good enough” algorithm for y...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
...problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try different parameters within each algorithm as well), and select the best one by cross-validation. But if you’re simply looking for a “good enough” algorithm for y...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
...problem? Of course, if you really care about accuracy, your best bet is to test out a couple different ones (making sure to try different parameters within each algorithm as well), and select the best one by cross-validation. But if you’re simply looking for a “good enough” algorithm for y...