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How to get number of rows using SqlDataReader in C#
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There are only two options:
Find out by reading all rows (and then you might as well store them)
run a specialized SELECT COUNT(*) query beforehand.
Going twice through the DataReader loop is really expensive, you would have to re-execute the query.
And (thanks to Pete ...
What is a StackOverflowError?
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Parameters and local variables are allocated on the stack (with reference types, the object lives on the heap and a variable in the stack references that object on the heap). The stack typically lives at the upper end of your address space and as it is used up...
Peak signal detection in realtime timeseries data
...andard deviations away from some moving mean, the algorithm signals (also called z-score). The algorithm is very robust because it constructs a separate moving mean and deviation, such that signals do not corrupt the threshold. Future signals are therefore identified with approximately the same accu...
BLE（二）信道&数据包&协议栈格式 - 创客硬件开发 - 清泛IT社区，...
文章源自：https://www.gandalf.site/2018/11/ble_23.html
参考低功耗蓝牙（BLE）安全初探
0x1 信道BLE的物理通道即“频道，分别是‘f=2402+k*2 MHz, k=0, … ,39’，带宽为2MHz”的40个RF Channel。
其中，有3个信道是advertising channel（广播通道）...
How to upgrade all Python packages with pip?
Is it possible to upgrade all Python packages at one time with pip ?
55 Answers
55
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How to detect orientation change?
... the notification var in your callback,
// you can safely replace it with _
var didRotate: (Notification) -> Void = { notification in
switch UIDevice.current.orientation {
case .landscapeLeft, .landscapeRight:
print("landscape")
case .portrait, .portraitUp...
Inserting a PDF file in LaTeX
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Use the pdfpages package.
\usepackage{pdfpages}
To include all the pages in the PDF file:
\includepdf[pages=-]{myfile.pdf}
To include just the first page of a PDF:
\includepdf[pages={1}]{myfile.pdf}
Run texdoc pdfpages in a shell to see the complete manual for pdfpages.
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How to capitalize the first character of each word in a string
...answers that refer to the commons libraries.
– Ravi Wallau
Dec 12 '09 at 8:59
11
To change the no...
Loop through files in a folder using VBA?
... bottom.
The way that I've handled this is to use the Dir function to get all of the sub-folders for the target folder and load them into an array, then pass the array into a function that recurses.
Here's a class that I wrote that accomplishes this, it includes the ability to search for filters....
Checking the equality of two slices
...swer, and more highly voted is simply maddening...
– allyourcode
Feb 12 '15 at 7:54
5
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