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Why is using “for…in” for array iteration a bad idea?

...5; // Perfectly legal JavaScript that resizes the array. for (var i = 0; i < a.length; i++) { // Iterate over numeric indexes from 0 to 5, as everyone expects. console.log(a[i]); } /* Will display: undefined undefined undefined undefined undefined 5 */ ...
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Making heatmap from pandas DataFrame

...5, 4)), index=index, columns=columns) plt.pcolor(df) plt.yticks(np.arange(0.5, len(df.index), 1), df.index) plt.xticks(np.arange(0.5, len(df.columns), 1), df.columns) plt.show() This gives: share | ...
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What's Go's equivalent of argv[0]?

...t my own program's name at runtime? What's Go's equivalent of C/C++'s argv[0]? To me it is useful to generate the usage with the right name. ...
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How to get the type of a variable in MATLAB?

... answered Feb 23 '09 at 17:36 Daniel LeCheminantDaniel LeCheminant 47.3k1515 gold badges115115 silver badges113113 bronze badges ...
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Calculate the center point of multiple latitude/longitude coordinate pairs

...ing them has weird edge cases with angles when they wrap from 359' back to 0'. A much earlier question on SO asked about finding the average of a set of compass angles. An expansion of the approach recommended there for spherical coordinates would be: Convert each lat/long pair into a unit-lengt...
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Efficiently test if a port is open on Linux?

...o use: exec 6<>/dev/tcp/ip.addr.of.server/445 echo -e "GET / HTTP/1.0\n" >&6 cat <&6 I'm using 6 as the file descriptor because 0,1,2 are stdin, stdout, and stderr. 5 is sometimes used by Bash for child processes, so 3,4,6,7,8, and 9 should be safe. As per the comment below, ...
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Why is isNaN(null) == false in JS?

...false. So in the specific case x = null, null is converted to the number 0, (try evaluating Number(null) and see that it returns 0,) and isNaN(0) returns false. A string that is only digits can be converted to a number and isNaN also returns false. A string (e.g. 'abcd') that cannot be converted t...
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Transposing a 2D-array in JavaScript

... 210 array[0].map((_, colIndex) => array.map(row => row[colIndex])); map calls a provided ...
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How to find Unused Amazon EC2 Security groups

... | edited Jul 1 at 20:15 Dherik 11.2k1010 gold badges7373 silver badges114114 bronze badges answer...
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Export database schema into SQL file

Is it possible in MS SQL Server 2008 to export database structure into a T-SQL file? 4 Answers ...