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Find integer index of rows with NaN in pandas dataframe
....:
df['a'].ix[index[0]]
>>> 1.452354
For the integer index:
df_index = df.index.values.tolist()
[df_index.index(i) for i in index]
>>> [3, 6]
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...
Why the switch statement cannot be applied on strings?
...er the string if you are using a predetermined set of strings:
enum string_code {
eFred,
eBarney,
eWilma,
eBetty,
...
};
string_code hashit (std::string const& inString) {
if (inString == "Fred") return eFred;
if (inString == "Barney") return eBarney;
...
}
voi...
Checkout one file from Subversion
... you have Subversion 1.5+, then do a sparse checkout:
svn checkout <url_of_big_dir> <target> --depth empty
cd <target>
svn up <file_you_want>
For an older version of SVN, you might benefit from the following:
Checkout the directory using a revision back in the distant pa...
Android search with Fragments
...le activity and delivers it the search
query in an Intent with the ACTION_SEARCH action. Your searchable
activity retrieves the query from the intent's QUERY extra, then
searches your data and presents the results.
The underlying, internal system that is responsible for providing search resu...
What is the performance of Objects/Arrays in JavaScript? (specifically for Google V8)
...V8's source, both implemented in JS itself:
function ArrayPop() {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.pop"]);
}
var n = TO_UINT32(this.length);
if (n == 0) {
...
Why doesn't Java allow to throw a checked exception from static initialization block?
...va.lang.ExceptionInInitializerError.
Sample code:
protected static class _YieldCurveConfigHelperSingleton {
public static YieldCurveConfigHelper _staticInstance;
static {
try {
_staticInstance = new YieldCurveConfigHelper();
}
catch (IOException | SAXE...
Update multiple columns in SQL
...
i think use 1keydata.com/sql/sqlupdate.html "SET column_1 = [value1], column_2 = [value2]"
– DeLe
Jun 9 '13 at 1:01
...
Different types of thread-safe Sets in Java
...e look up time would be O(lg n) and not O(n).
– akhil_mittal
Dec 28 '17 at 4:58
...
Https Connection Android
...rify the host - dont check for certificate
final static HostnameVerifier DO_NOT_VERIFY = new HostnameVerifier() {
public boolean verify(String hostname, SSLSession session) {
return true;
}
};
/**
* Trust every server - dont check for any certificate
*/
private static void trustAl...
PHP & mySQL: Year 2038 Bug: What is it? How to solve it?
...me the old TIMESTAMP field
ALTER TABLE `myTable` CHANGE `myTimestamp` `temp_myTimestamp` int(11) NOT NULL;
# create a new DATETIME column of the same name as your old column
ALTER TABLE `myTable` ADD `myTimestamp` DATETIME NOT NULL;
# update all rows by populating your new DATETIME field
UPDATE `m...