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Replacement for “rename” in dplyr

...sp hp drat wt qsec vs am gear carb Mazda RX4 21.0 6 160 110 3.90 2.620 16.46 0 1 4 4 Mazda RX4 Wag 21.0 6 160 110 3.90 2.875 17.02 0 1 4 4 Datsun 710 22.8 4 108 93 3.85 2.320 18.61 1 1 4 1 Hornet 4 Drive 21.4 6 258 110 3.08 ...
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What is the best way to use a HashMap in C++?

...al hash values for first, // second and third and combine them using XOR // and bit shifting: return ((hash<string>()(k.first) ^ (hash<string>()(k.second) << 1)) >> 1) ^ (hash<int>()(k.third) << 1); } }; } ...
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Search all tables, all columns for a specific value SQL Server [duplicate]

... @TableName nvarchar(256), @ColumnName nvarchar(128), @SearchStr2 nvarchar(110) SET  @TableName = '' SET @SearchStr2 = QUOTENAME('%' + @SearchStr + '%','''')   WHILE @TableName IS NOT NULL   BEGIN SET @ColumnName = '' SET @TableName = ( SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '....
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Why does X[Y] join of data.tables not allow a full outer join, or a left join?

...and Y rows where there is no match to the other table, ie an exclusive-or (XOR) "cross" -- cross join or Cartesian product with each row of X matched to each row of Y The default value is join="all.y" which corresponds to the present default. The "all", "all.x" and "all.y" string values correspo...
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How can I find the data structure that represents mine layout of Minesweeper in memory?

... .text:01003687 push edi .text:01003688 xor edi, edi .text:0100368A cmp eax, dword_1005334 .text:01003690 mov dword_1005164, edi .text:01003696 jnz short loc_10036A4 .text:01003696 .text:01003698 ...
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Search for one value in any column of any table inside a database

... @TableName nvarchar(256), @ColumnName nvarchar(128), @SearchStr2 nvarchar(110) SET @TableName = '' SET @SearchStr2 = QUOTENAME('%' + @SearchStr + '%','''') WHILE @TableName IS NOT NULL BEGIN SET @ColumnName = '' SET @TableName = ( SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '.' + QU...
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Select first 4 rows of a data.frame in R

... no male no 12 6.100 13 59.4 no male no 13 6.110 14 59.5 no male no 14 6.120 15 59.6 no male no 15 6.130 16 59.7 no male no Let's say, you want to select the first 10 rows. The easiest way to do it would be data[1:10, ]...
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Facebook API - How do I get a Facebook user's profile image through the Facebook API (without requir

... example, https://graph.facebook.com/redbull/picture?width=140&height=110 returns { "data": { "url": "https://fbcdn-profile-a.akamaihd.net/hprofile-ak-ash4/c0.19.180.142/s148x148/2624_134501175351_4831452_a.jpg", "width": 148, "height": 117, "is_silh...
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Is “double hashing” a password less secure than just hashing it once?

...ng 56 => 107 Hashing 57 => 108 Hashing 58 => 109 Hashing 59 => 110 Hashing 60 => 102 Hashing 61 => 103 Hashing 62 => 104 Hashing 63 => 105 Hashing 64 => 106 Hashing 65 => 107 Hashing 66 => 108 Hashing 67 => 109 Hashing 68 => 110 Hashing 69 => 111 Hashing 70 ...
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Differences in boolean operators: & vs && and | vs ||

... Those are the bitwise AND and bitwise OR operators. int a = 6; // 110 int b = 4; // 100 // Bitwise AND int c = a & b; // 110 // & 100 // ----- // 100 // Bitwise OR int d = a | b; // 110 // | 100 // ----- // 110 System.out.println(c); // 4 System.out.println(d); // 6...