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Printf width specifier to maintain precision of floating-point value
... in:
#include <float.h>
int Digs = DECIMAL_DIG;
double OneSeventh = 1.0/7.0;
printf("%.*e\n", Digs, OneSeventh);
// 1.428571428571428492127e-01
But let's dig deeper ...
Mathematically, the answer is "0.142857 142857 142857 ...", but we are using finite precision floating point numbers.
L...
How to redirect output to a file and stdout
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10 Answers
10
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Regular expression search replace in Sublime Text 2
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Usually a back-reference is either $1 or \1 (backslash one) for the first capture group (the first match of a pattern in parentheses), and indeed Sublime supports both syntaxes. So try:
my name used to be \1
or
my name used to be $1
Also note that your or...
How do I compare two strings in Perl?
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186
See perldoc perlop. Use lt, gt, eq, ne, and cmp as appropriate for string comparisons:
Binary...
Replacing Pandas or Numpy Nan with a None to use with MysqlDB
...n use where, it's worth noting that you can do this natively in pandas:
df1 = df.where(pd.notnull(df), None)
Note: this changes the dtype of all columns to object.
Example:
In [1]: df = pd.DataFrame([1, np.nan])
In [2]: df
Out[2]:
0
0 1
1 NaN
In [3]: df1 = df.where(pd.notnull(df), None...
UnicodeDecodeError, invalid continuation byte
Why is the below item failing? Why does it succeed with "latin-1" codec?
10 Answers
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How to compare two floating point numbers in Bash?
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17 Answers
17
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Test if a vector contains a given element
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521
Both the match() (returns the first appearance) and %in% (returns a Boolean) functions are desig...