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Differences between numpy.random and random.random in Python
...nd any evidence to the contrary).
The numpy.random library contains a few extra probability distributions commonly used in scientific research, as well as a couple of convenience functions for generating arrays of random data. The random.random library is a little more lightweight, and should be fi...
Why is a round-trip conversion via a string not safe for a double?
...amp;number, &dTest);
if (dTest == value) {
gc.refRetVal = NumberToString(&number, 'G', DOUBLE_PRECISION, gc.numfmt);
goto lExit;
}
DoubleToNumber(value, 17, &number);
DoubleToNumber is pretty simple -- it just calls _ecvt, which is in the C runtime:
void DoubleToNumber(doubl...
Difference between Convert.ToString() and .ToString()
What is the difference between Convert.ToString() and .ToString() ?
19 Answers
19
...
Conditional HTML Attributes using Razor MVC3
... For example:
<button type="button" @(true ? "style=\"border:0px\"" : string.Empty)>
This should evaluate to <button type="button" style="border:0px"> but Razor escapes all output from C# and thus produces:
style=&quot;border:0px&quot;
You will only see this if you view th...
How to pass objects to functions in C++?
... C tmp = a;
a = b;
b = tmp;
}
public static void main( String args[] ) {
C a = new C();
C b = new C();
C old_a = a;
C old_b = b;
swap( a, b );
// a and b remain unchanged a==old_a, and b==old_b
}
}
The Java version of the code will modify...
Count how many records are in a CSV Python?
...e number of LINES in the csv file. But some CSV files will contain quoted strings which themselves contain newline characters. MS CSV files usually delimit records with \r\n, but use \n alone within quoted strings.
For a file like this, counting lines of text (as delimited by newline) in the file...
Read/Write String from/to a File in Android
...ed from EditText. Then I want the same file to return the inputted text in String form and save it to another String which is to be used later.
...
Filter rows which contain a certain string
...filter a data frame using as criterion those row in which is contained the string RTB .
4 Answers
...
How to check if running in Cygwin, Mac or Linux?
...he system information (-s parameter).
Use expr and substr to deal with the string.
Use if elif fi to do the matching job.
You can add more system support if you want, just follow the uname -s specification.
Implementation
#!/usr/bin/env bash
if [ "$(uname)" == "Darwin" ]; then
# Do something...
Django dynamic model fields
... to end up storing thousands of items in one field. It also only supports strings for values.
#app/models.py
from django.contrib.postgres.fields import HStoreField
class Something(models.Model):
name = models.CharField(max_length=32)
data = models.HStoreField(db_index=True)
In Django's s...