I try batch-processing some files with GIMP.
Here is the script:
(define (script-fu-batch-sofu globexp)
(define (sofu-trans-img n f)
(let* ((fname (car f))
(img (car (gimp-file-load 1 fname fname))))
(gimp-image-undo-disable img)
(gimp-fuzzy-select (car (gimp-image-get-active-drawable img)) 0 0 10 2 FALSE FALSE 0 FALSE)
(gimp-selection-grow img 1)
(gimp-edit-clear (car (gimp-image-get-active-drawable img)))
(file-png-save-defaults non-interactive img (car (gimp-image-get-active-drawable img)) fname fname)
(gimp-image-delete img)
)
(if (= n 1) 1 (sofu-trans-img (- n 1) (cdr f)))
)
(set! files (file-glob globexp 0))
(sofu-trans-img (car files) (car (cdr files)))
)
; Im GIMP und im Menü registrieren
(script-fu-register "script-fu-batch-sofu"
_"_Mehrere Bilder transparentieren…"
_"Mehrere Bilder auf einmal transparent machen"
"Martin Weber"
"2012, Martin Weber"
"Sep 5, 2012"
""
SF-STRING "Zu transparentierende Dateien" "/pfad/zu/bildern/*.bmp")
(script-fu-menu-register "script-fu-batch-sofu" "<Image>/Xtns/Misc")
I basically copied a script from a tutorial and modified the lines where the image is processed.
If i run the script, i get this error message:
Error: set!: unbound variable: files
To be honest, i don't really know what that part does, but i think i need it.
I guess it opens the Files given by the script-parameter and precesses them one after the other.
I just don't know what is wrong there. What did i miss?
I think that you need to add
(define files)
at the first line of your code.
Related
I am requiring two modules to my file:
(require sicp) ; contains set-car! and set-cdr!
(require (planet dyoo/sicp-concurrency:1:2/sicp-concurrency)) ; contains procedures parallel-execute and test-and-set!
Problem: both libraries use different flavors of scheme. The sicp-concurrency uses mzscheme. Requiring this module prevented me from using else in a cond clause.
Is there a way to prevent the features of mzscheme in sicp-concurrency while still making use of the procedures I needed?
I have updated Danny Yoo's code to Racket 7.
Get the new file "sicp-concurrency.rkt" here:
https://gist.github.com/soegaard/d32e12d89705c774b71ee78ef930a4bf
Save the file in the same folder as your program file.
Here is an example of use:
#lang sicp
(#%require "sicp-concurrency.rkt")
(define (test-1)
(define x 10)
(parallel-execute (lambda () (set! x (* x x)))
(lambda () (set! x (+ x 1))))
x)
(define (test-2)
(define x 10)
(define s (make-serializer))
(parallel-execute (s (lambda () (set! x (* x x))))
(s (lambda () (set! x (+ x 1)))))
x)
(test-1)
(test-1)
(test-1)
(test-1)
(test-1)
I'm a newbie to scheme programming and I was writing small codes when I encountered the following issue and couldn't reason about it satisfactorily.
(define (at_i lst i)
(if (eq? i 0)
(car lst)
(at_i (cdr lst)
(- i 1) )))
Evaluation of (at_i '(1 2 3 4) 0) returns 1.
Now lets define same procedure with a lambda syntax.
(define (at_i lst i)
(lambda (vec x)
(if (eq? x 0)
(car vec)
(at_i (cdr vec)
(- x 1) )))
lst i)
But now Evaluation of (at_i '(1 2 3 4) 0) returns 0, which is not in the list and in general, it returns element at index-1.
I don't understand why this is happening.
Note: I just realized its not returning element at index - 1 but the index itself. The reason for this has been well explained below by #Renzo. Thanks!
First, you should indent properly the code if you intend to learn the language, since code indentation is very important to understand programs in Scheme and Lisp-like languages.
For instance, your function correctly indented is:
(define (at_i lst i)
(lambda (vec x)
(if (eq? x 0)
(car vec)
(at_i (cdr vec) (- x 1))))
lst
i)
From this you can see that you are defining the function at_i exactly as before in terms of a function with two parameters (lst and i), and whose body is constitued by three expressions: the first lambda (vec x) ... (- x 1)))), which is an (anonymous) function (lambda) which is not called or applied, the second, which is the first parameter lst, and finally the third which is the second parameter i. So, when the function at_i is called with two arguments, the result is the evaluation of the three expressions in sequence, the first two values are discarded (the function and the value of lst), and the result is the value of the second parameter i. This is reason for which the result of (at_i '(1 2 3 4) 0) is 0, since it is the value of i.
A proper redefinition of the function in lambda form would be the following, for instance:
(define at_i
(lambda (vec x)
(if (eq? x 0)
(car vec)
(at_i (cdr vec) (- x 1)))))
(at_i '(1 2 3 4) 0) ;; => 1
in which you can see that the name at_i, through the define, is associated to a two parameter function which calculates correctly the result.
eq? is memory object equality. Only some Scheme implementations interpret (eq? 5 5) as #t. Use = for numbers, eqv? for values, and equal? for collections.
(define (index i xs) ; `index` is a partial function,
(if (= i 0) ; `i` may go out of range
(car xs)
(index (- i 1) ; Tail recursion
(cdr xs) )))
Your second function returns the index because you missed parenthesis around the lambda's application. It should be
(define (index i xs)
((lambda (i' xs')
(if (= i' 0)
(car xs')
(index (- i' 1) ; Not tail-recursive
(cdr xs') )))
i xs))
But this is verbose and differs semantically from the first formulation.
You say you are defining the "same procedure with a lambda syntax", but you are not. That would be (define at_i (lambda lst i) ...). Instead, you are effectively saying (define (at_i lst i) 1 2 3), and that is 3, of course.
In your particular case, you defined the procedure at_i to return (lambda (vec x) ...), lst and i. Now, if you call (at_i '(1 2 3 4) 0), the procedure will return 0, since that is the value of i at this point.
i am new to racket. i am trying create a list from the input of the user and when the value 0 is entred the first three elements are printed.
here is the code:
#lang racket
(define lst '())
(define (add)
(define n(read))
(if (= n 0)
;then
(
list (car lst) (cadr lst) (caddr lst)
)
;else
(
(set! lst (append lst (list n)))
(add)
)
)
)
(add)
i tested the program with the values 1 2 3 4 5 0
but i keep getting this error:
application: not a procedure;
expected a procedure that can be applied to arguments
given: #<void>
arguments...:
'(1 2 3)
can anyone help me figure out what's wrong.
If you have more than one expression in the "then" or "else" parts, you must enclose them inside a begin, because a pair of () in Scheme are used for function application - that explains the error you're getting. Try this:
(define (add)
(define n (read))
(if (= n 0)
; then
(list (car lst) (cadr lst) (caddr lst))
; else
(begin
(set! lst (append lst (list n)))
(add))))
I had a similar problem, in a function i called a parameter with the same name of a structure, so, trying to create an instance of that structure i got the same error.
example:
> (struct example (param1 param2) #:transparent)
> (define e (example 1 2))
> e
(example 1 2)
> (define (fn e)
(example (example-param1 e) 0))
> (fn e)
(example 1 0)
> (define (fn example)
(example (example-param1 example) 0))
> (fn e)
application: not a procedure;
expected a procedure that can be applied to arguments
given: (example 1 2)
arguments...:
I hope this helps
Your code have a few problems, for example it will fail if you enter less than 3 elements. Also, it is not considered good style to define variables at the module level.
I'd suggest the following:
(define (add)
(define (sub cnt lst)
(define n (read))
(if (= n 0)
(reverse lst)
(if (< cnt 3)
(sub (add1 cnt) (cons n lst))
(sub cnt lst))))
(sub 0 '()))
I am working with a score in Lilypond that has a lot of repetitions, where basically every bar has to be repeated a certain number of times. I would like to be able to write above every bar the number of times it should be repeat, similar to the score below (which was not created in Lilypond):
It would be great to be able to have some brackets above the bar and also to have the "3x" centralized, just like in the example above. So far, the only (temporary) solution I was able to come up with in Lilypond was to add repeat bars and then simply write "3x" above the first note of every bar (since I could not have it centralized on the bar either). It does not look very good, but gets the job done. This temporary solution looks like this:
Any suggestions of how to make this example look more similar to the first inn Lilypond would be extremely welcome!
This is a workaround for this problem:
\version "2.19.15"
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% COPY ALL THIS BELOW %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% repeatBracket snippet
% will add .----Nx----. above a bar, where N is the number of repetitions
% based on the wonderful spanner by David Nalesnik (see: http://lists.gnu.org/archive/html/lilypond-user/2014-10/msg00446.html )
#(define (test-stencil grob text)
(let* ((orig (ly:grob-original grob))
(siblings (ly:spanner-broken-into orig)) ; have we been split?
(refp (ly:grob-system grob))
(left-bound (ly:spanner-bound grob LEFT))
(right-bound (ly:spanner-bound grob RIGHT))
(elts-L (ly:grob-array->list (ly:grob-object left-bound 'elements)))
(elts-R (ly:grob-array->list (ly:grob-object right-bound 'elements)))
(break-alignment-L
(filter
(lambda (elt) (grob::has-interface elt 'break-alignment-interface))
elts-L))
(break-alignment-R
(filter
(lambda (elt) (grob::has-interface elt 'break-alignment-interface))
elts-R))
(break-alignment-L-ext (ly:grob-extent (car break-alignment-L) refp X))
(break-alignment-R-ext (ly:grob-extent (car break-alignment-R) refp X))
(num
(markup text))
(num
(if (or (null? siblings)
(eq? grob (car siblings)))
num
(make-parenthesize-markup num)))
(num (grob-interpret-markup grob num))
(num-stil-ext-X (ly:stencil-extent num X))
(num-stil-ext-Y (ly:stencil-extent num Y))
(num (ly:stencil-aligned-to num X CENTER))
(num
(ly:stencil-translate-axis
num
(+ (interval-length break-alignment-L-ext)
(* 0.5
(- (car break-alignment-R-ext)
(cdr break-alignment-L-ext))))
X))
(bracket-L
(markup
#:path
0.1 ; line-thickness
`((moveto 0.5 ,(* 0.5 (interval-length num-stil-ext-Y)))
(lineto ,(* 0.5
(- (car break-alignment-R-ext)
(cdr break-alignment-L-ext)
(interval-length num-stil-ext-X)))
,(* 0.5 (interval-length num-stil-ext-Y)))
(closepath)
(rlineto 0.0
,(if (or (null? siblings) (eq? grob (car siblings)))
-1.0 0.0)))))
(bracket-R
(markup
#:path
0.1
`((moveto ,(* 0.5
(- (car break-alignment-R-ext)
(cdr break-alignment-L-ext)
(interval-length num-stil-ext-X)))
,(* 0.5 (interval-length num-stil-ext-Y)))
(lineto 0.5
,(* 0.5 (interval-length num-stil-ext-Y)))
(closepath)
(rlineto 0.0
,(if (or (null? siblings) (eq? grob (last siblings)))
-1.0 0.0)))))
(bracket-L (grob-interpret-markup grob bracket-L))
(bracket-R (grob-interpret-markup grob bracket-R))
(num (ly:stencil-combine-at-edge num X LEFT bracket-L 0.4))
(num (ly:stencil-combine-at-edge num X RIGHT bracket-R 0.4)))
num))
#(define-public (Measure_attached_spanner_engraver context)
(let ((span '())
(finished '())
(event-start '())
(event-stop '()))
(make-engraver
(listeners ((measure-counter-event engraver event)
(if (= START (ly:event-property event 'span-direction))
(set! event-start event)
(set! event-stop event))))
((process-music trans)
(if (ly:stream-event? event-stop)
(if (null? span)
(ly:warning "You're trying to end a measure-attached spanner but you haven't started one.")
(begin (set! finished span)
(ly:engraver-announce-end-grob trans finished event-start)
(set! span '())
(set! event-stop '()))))
(if (ly:stream-event? event-start)
(begin (set! span (ly:engraver-make-grob trans 'MeasureCounter event-start))
(set! event-start '()))))
((stop-translation-timestep trans)
(if (and (ly:spanner? span)
(null? (ly:spanner-bound span LEFT))
(moment<=? (ly:context-property context 'measurePosition) ZERO-MOMENT))
(ly:spanner-set-bound! span LEFT
(ly:context-property context 'currentCommandColumn)))
(if (and (ly:spanner? finished)
(moment<=? (ly:context-property context 'measurePosition) ZERO-MOMENT))
(begin
(if (null? (ly:spanner-bound finished RIGHT))
(ly:spanner-set-bound! finished RIGHT
(ly:context-property context 'currentCommandColumn)))
(set! finished '())
(set! event-start '())
(set! event-stop '()))))
((finalize trans)
(if (ly:spanner? finished)
(begin
(if (null? (ly:spanner-bound finished RIGHT))
(set! (ly:spanner-bound finished RIGHT)
(ly:context-property context 'currentCommandColumn)))
(set! finished '())))
(if (ly:spanner? span)
(begin
(ly:warning "I think there's a dangling measure-attached spanner :-(")
(ly:grob-suicide! span)
(set! span '())))))))
\layout {
\context {
\Staff
\consists #Measure_attached_spanner_engraver
\override MeasureCounter.font-encoding = #'latin1
\override MeasureCounter.font-size = 0
\override MeasureCounter.outside-staff-padding = 2
\override MeasureCounter.outside-staff-horizontal-padding = #0
}
}
repeatBracket = #(define-music-function
(parser location N note)
(number? ly:music?)
#{
\override Staff.MeasureCounter.stencil =
#(lambda (grob) (test-stencil grob #{ #(string-append(number->string N) "×") #} ))
\startMeasureCount
\repeat volta #N { $note }
\stopMeasureCount
#}
)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% ...UNTIL HERE %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
{
\repeatBracket 7 {c'1}
\repeatBracket 32 {d' g}
\repeatBracket 14 {e' f g}
\repeatBracket 29 {f' a bes \break cis' e''}
\repeatBracket 1048 {g'1}
}
This code above gives the following result:
]
This solution was not created by myself, but sent to me by David Nalesnik, from lilypond-user mailing list. I just would like to share it here in case someone would need it as well. I've made just some very minor adjustments to what David sent me.
I just had a similar problem but preferred the style on your second example, with the 3x above the bar. The solution I found was:
f e d c |
\mark \markup {"3x"}\repeat volta 3 {c d e f}
f e d c |
generating
Maybe someone else has a use for it.
So I have to finish a project in Scheme and I'm pretty stuck. Basically, what the program does is open a file and output the statistics. Right now I am able to count the number of characters, but I also need to count the number of lines and words. I'm just trying to tackle this situation for now but eventually I also have to take in two files - the first being a text file, like a book. The second will be a list of words, I have to count how many times those words appear in the first file. Obviously I'll have to work with lists but I would love some help on where to being. Here is the code that I have so far (and works)
(define filestats
(lambda (srcf wordcount linecount charcount )
(if (eof-object? (peek-char srcf ) )
(begin
(close-port srcf)
(display linecount)
(display " ")
(display wordcount)
(display " ")
(display charcount)
(newline) ()
)
(begin
(read-char srcf)
(filestats srcf 0 0 (+ charcount 1))
)
)
)
)
(define filestatistics
(lambda (src)
(let ((file (open-input-file src)))
(filestats file 0 0 0)
)
)
)
How about 'tokenizing' the file into a list of lines, where a line is a list of words, and a word is a list of characters.
(define (tokenize file)
(with-input-from-file file
(lambda ()
(let reading ((lines '()) (words '()) (chars '()))
(let ((char (read-char)))
(if (eof-object? char)
(reverse lines)
(case char
((#\newline) (reading (cons (reverse (cons (reverse chars) words)) lines) '() '()))
((#\space) (reading lines (cons (reverse chars) words) '()))
(else (reading lines words (cons char chars))))))))))
once you've done this, the rest is trivial.
> (tokenize "foo.data")
(((#\a #\b #\c) (#\d #\e #\f))
((#\1 #\2 #\3) (#\x #\y #\z)))
The word count algorithm using Scheme has been explained before in Stack Overflow, for example in here (scroll up to the top of the page to see an equivalent program in C):
(define (word-count input-port)
(let loop ((c (read-char input-port))
(nl 0)
(nw 0)
(nc 0)
(state 'out))
(cond ((eof-object? c)
(printf "nl: ~s, nw: ~s, nc: ~s\n" nl nw nc))
((char=? c #\newline)
(loop (read-char input-port) (add1 nl) nw (add1 nc) 'out))
((char-whitespace? c)
(loop (read-char input-port) nl nw (add1 nc) 'out))
((eq? state 'out)
(loop (read-char input-port) nl (add1 nw) (add1 nc) 'in))
(else
(loop (read-char input-port) nl nw (add1 nc) state)))))
The procedure receives an input port as a parameter, so it's possible to apply it to, say, a file. Notice that for counting words and lines you'll need to test if the current char is either a new line character or a white space character. And an extra flag (called state in the code) is needed for keeping track of the start/end of a new word.