Re: How to count the number of occurrences of a character in a string?

[Kaushal Modi <kaushal.modi@gmail.com>]

Looks like mapcar is
​now at ​
the 2nd place by a hair.. mapc drops down to 3rd place
​. Updated https://gist.github.com/kaushalmodi/ab487f63727381179f61​
​

;; Fastest to slowest approach;;;;
|------+--------------+-----------------------|;; | Rank | Method | Time in
second |;; | | | for 100000 executions |;; | | | (very rough avg) |;;
|------+--------------+-----------------------|;; | 1 | cl-count | 1.0 to
1.6 |;; | 2 | mapcar | 1.9 to 2.1 |;; | 3 | mapc | 2.0 to 2.6 |;; | 4 | cdr
| 2.4 to 3.3 |;; | 5 | split-string | 4.0 to 4.7 |;; | 5* | string-match |
3.7 to 4.7 |;; |------+--------------+-----------------------|
​


​


--
Kaushal Modi

On Tue, Oct 13, 2015 at 4:46 PM, Brendan Halpin <brendan.halpin@ul.ie>
wrote:

> On Tue, Oct 13 2015, Eli Zaretskii wrote:
>
> > Also, did you actually try 'mapc', per my second suggestion?
>
> Why not mapcar?
>
> (defun test (str char)
>   (apply '+ (mapcar (lambda (x) (if (= x char) 1 0))
>                     str)))
>
> B
> --
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> Ireland
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