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I have a long table in this form:

A = {{a, 1}, {c, 2}, {b, 5}, {c, 1}, {a, 14}, {b, 7}, {b, 10}, {c, 6}, {a, 4}}

and I want to order it by the second column, but first all with an "a" in the first element should be ordered. And then by order of appearance. It should look like this:

{{a, 1},{a, 4},{a, 14},{c, 1},{c, 2},{c, 6},{b, 5},{b, 7},{b, 10}}

SortBy[A, #[[2]] &] would sort the second column, ignoring the first.

Any ideas? Maybe a for-loop?

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    $\begingroup$ So, you don't want SortBy[A, {#[[1]] &, #[[2]] &}]? $\endgroup$ – J. M. will be back soon♦ Mar 31 '17 at 12:50
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    $\begingroup$ Why don't you use just Sort[A] ? $\endgroup$ – Artes Mar 31 '17 at 12:52
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    $\begingroup$ If you want it as in the OP, just try Sort /@ GatherBy[A, First]. $\endgroup$ – Artes Mar 31 '17 at 12:59
  • $\begingroup$ Thank you! Sort /@ GatherBy[A, First] was what I wanted. The other two answers would also sort the first element alphabetically. I wanted it by order of appearance. $\endgroup$ – drcyberz Mar 31 '17 at 13:34
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From Artes' comment:

A = {{a, 1}, {c, 2}, {b, 5}, {c, 1}, {a, 14}, {b, 7}, {b, 10}, {c, 6}, {a, 4}};
Sort /@ GatherBy[A, First]

{{{a, 1}, {a, 4}, {a, 14}}, {{c, 1}, {c, 2}, {c, 6}}, {{b, 5}, {b, 7}, {b, 10}}}

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    $\begingroup$ To get the specified output you need to include a Flatten: Flatten[Sort /@ GatherBy[A, First], 1] $\endgroup$ – Bob Hanlon Mar 31 '17 at 16:45
  • $\begingroup$ Or Catenate instead of Flatten. $\endgroup$ – corey979 Mar 31 '17 at 16:55

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