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Objective-C and Swift URL encoding
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To escape the characters you want is a little more work.
Example code
iOS7 and above:
NSString *unescaped = @"http://www";
NSString *escapedString = [unescaped stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLHo...
Entity Framework: “Store update, insert, or delete statement affected an unexpected number of rows (
...ndo UI does not support composite key, but in case I added new column that concat-ed my keys to one, what's happening then?
– Branislav
Nov 11 '13 at 21:39
add a comment
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C/C++ NaN constant (literal)?
...> offers the below functions:
#include <math.h>
double nan(const char *tagp);
float nanf(const char *tagp);
long double nanl(const char *tagp);
which are like their strtod("NAN(n-char-sequence)",0) counterparts and NAN for assignments.
// Sample C code
uint64_t u64;
double x;
x = nan("0...
What is the difference between join and merge in Pandas?
...ral methods to deal with these situations, among them merge, join, append, concat, combine, combine_first. Take a look at each of these to have a glimpse about which one would be the best fit for your situation
– xiaxio
Mar 29 at 19:03
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Creating a daemon in Linux
...nlog(3), closelog(3)
And here is a more general function,
int
daemonize(char* name, char* path, char* outfile, char* errfile, char* infile )
{
if(!path) { path="/"; }
if(!name) { name="medaemon"; }
if(!infile) { infile="/dev/null"; }
if(!outfile) { outfile="/dev/null"; }
if(!e...
Is there a difference between YES/NO,TRUE/FALSE and true/false in objective-c?
...them from their #define values.
Importantly, never test booleans using a character comparison -- it's not only risky because someVar could be assigned a non-zero value which is not YES, but, in my opinion more importantly, it fails to express the intent correctly:
if(someVar==YES) { ... } // don'...
Get all non-unique values (i.e.: duplicate/more than one occurrence) in an array
... i, arr) => arr.indexOf(v) !== i && acc.indexOf(v) === -1 ? acc.concat(v) : acc, [])
– ZephDavies
Nov 29 '18 at 14:56
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Maximum length of the textual representation of an IPv6 address?
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45 characters.
You might expect an address to be
0000:0000:0000:0000:0000:0000:0000:0000
8 * 4 + 7 = 39
8 groups of 4 digits with 7 : between them.
But if you have an IPv4-mapped IPv6 address, the last two groups can b...
Limits of Nat type in Shapeless
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Here is an example of a Concat type class that allows to concatenate two type-level strings via a macro. A type class for summing type-level integers would probably look very similar.
– Frank S. Thomas
Apr 16 '...
Combine two columns of text in pandas dataframe
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if both columns are strings, you can concatenate them directly:
df["period"] = df["Year"] + df["quarter"]
If one (or both) of the columns are not string typed, you should convert it (them) first,
df["period"] = df["Year"].astype(str) + df["quarter"]
Beware...