Suppose I have a file tools.m4 with macro definitions:
define([YEAR_2_DIGITS], substr(YEAR, [2], [2]))
I want to use in another file query.sql:
changequote(`[', `]')
include(./tools.m4)
define([YEAR], [2017])
YEAR_2_DIGITS
But obviously it will return:
$ m4 query.sql
AR
instead of 17.
Is there a workaround to make that construct work?
I finally did it. One has to quote the body of the first definition:
define([YEAR_2_DIGITS], [substr(YEAR, [2], [2])])
Related
I am using clingo to solve a homework problem and stumbled upon something I can't explain:
normalized(0,0).
normalized(A,1) :-
A != 0.
normalized(10).
In my opinion, normalized should be 0 when the first parameter is 0 or 1 in every other case.
Running clingo on that, however, produces the following:
test.pl:2:1-3:12: error: unsafe variables in:
normalized(A,1):-[#inc_base];A!=0.
test.pl:2:12-13: note: 'A' is unsafe
Why is A unsafe here?
According to Programming with CLINGO
Some error messages say that the program
has “unsafe variables.” Such a message usually indicates that the head of one of
the rules includes a variable that does not occur in its body; stable models of such
programs may be infinite.
But in this example A is present in the body.
Will clingo produce an infinite set consisting of answers for all numbers here?
I tried adding number(_) around the first parameter and pattern matching on it to avoid this situation but with the same result:
normalized(number(0),0).
normalized(A,1) :-
A=number(B),
B != 0.
normalized(number(10)).
How would I write normalized properly?
With "variables occuring in the body" actually means in a positive literal in the body. I can recommend the official guide: https://github.com/potassco/guide/releases/
The second thing, ASP is not prolog. Your rules get grounded, i.e. each first order variable is replaced with its domain. In your case A has no domain.
What would be the expected outcome of your program ?
normalized(12351,1).
normalized(my_mom,1).
would all be valid replacements for A so you create an infinite program. This is why 'A' has to be bounded by a domain. For example:
dom(a). dom(b). dom(c). dom(100).
normalized(0,0).
normalized(A,1) :- dom(A).
would produce
normalize(0,0).
normalize(a,1).
normalize(b,1).
normalize(c,1).
normalize(100,1).
Also note that there is no such thing as number/1. ASP is a typefree language.
Also,
normalized(10).
is a different predicate with only one parameter, I do not know how this will fit in your program.
Maybe your are looking for something like this:
dom(1..100).
normalize(0,0).
normalize(X,1) :- dom(X).
foo(43).
bar(Y) :- normalize(X,Y), foo(X).
I am writing an Airflow DAG to pull data from an API and store it in a database I own. Following best practices outlined in We're All Using Airflow Wrong, I'm writing the DAG as a sequence of KubernetesPodOperators that run pretty simple Python functions as the entry point to the Docker image.
The problem I'm trying to solve is that this DAG should only pull data for the execution_date.
If I was using a PythonOperator (doc), I could use the provide_context argument to make the execution date available to the function. But judging from the KubernetesPodOperator's documentation, it seems that the Kubernetes operator has no argument that does what provide_context does.
My best guess is that you could use the arguments command to pass in a date range, and since it's templated, you can reference it like this:
my_pod_operator = KubernetesPodOperator(
# ... other args here
arguments=['python', 'my_script.py', '{{ ds }}'],
# arguments continue
)
And then you'd get the start date like you'd get any other argument provided to a Python file run as a script, by using sys.argv.
Is this the right way of doing it?
Thanks for the help.
Yes, that is the correct way of doing it.
Each Operator would have template_fields. All the parameters listed in template_fields can render Jinja2 templates and Airflow Macros.
For KubernetesPodOperator, if you check docs, you would find:
template_fields = ['cmds', 'arguments', 'env_vars', 'config_file']
which means you can pass '{{ ds }}'to any of the four params listed above.
I am using scopt to parse command line arguments in scala. I want it to be able to parse options with more than one value. For instance, the range option, if specified, should take exactly two values.
--range 25 45
Coming, from python background, I am basically looking for a way to do the following with scopt instead of python's argparse:
parser.add_argument("--range", default=None, nargs=2, type=float,
metavar=('start', 'end'),
help=(" Foo bar start and stop "))
I dont think minOccurs and maxOccurs solves my problem exactly, nor the key:value example in its help.
Looking at the source code, this is not possible. The Read type class used has a member tuplesToRead, but it doesn't seem to be working when you force it to 2 instead of 1. You will have to make a feature request, I guess, or work around this by using --min 25 --max 45, or --range '25 45' with a custom Read instance that splits this string into two parts. As #roterl noted, this is not a standard way of parsing.
It should be ok if only your values are delimited with something else than a space...
--range 25-45
... although you need to split them manually. Parse it with something like:
opt[String]('r', "range").action { (x, c) =>
val rx = "([0-9]+)\\-([0-9]+)".r
val rx(from, to) = x
c.copy(from = from.toInt, to = to.toInt)
}
// ...
println(s" Got range ${parsedArgs.from}..${parsedArgs.to}")
I have a makefile with the following format. First I define what my outputs are;
EXEFILES = myexe1.exe myexe2.exe
Then I define what the dependencies are for those outputs;
myexe1.exe : myobj1.obj
myexe2.exe : myobj2.obj
Then I have some macros that define extra dependencies for linking;
DEP_myexe1 = lib1.lib lib2.lib
DEP_myexe2 = lib3.lib lib4.lib
Then I have the target for transforming .obj to .exe;
$(EXEFILES):
$(LINK) -OUT:"Exe\$#" -ADDOBJ:"Obj\$<" -IMPLIB:$($($(DEP_$*)):%=Lib\\%)
What I want to happen is (example for myexe1.exe)
DEP_$* -> DEP_myexe1
$(DEP_myexe1) -> lib1.lib lib2.lib
$(lib1.lib lib2.lib:%=Lib\\%) -> Lib\lib1.lib Lib\lib2.lib
Unfortunately this is not working. When I run make --just-print, the -IMPLIB: arguments are empty. However, if I run $(warning DEP_$*) I get
DEP_myexe1
And when I run $(warning $(DEP_myexe1)) I get
lib1.lib lib2.lib
So for some reason, make does not like the combination of $(DEP_$*). Perhaps it cannot resolve macro names dynamically like this. What can I do to get this to work? Is there an alternative?
Where does $(warning DEP_$*) give you DEP_myexe1 as output exactly? Because given your makefile above it shouldn't.
$* is the stem of the target pattern that matched. In your case, because you have explicit target names, you have no patten match and so no stem and so $* is always empty.
Additionally, you are attempting a few too many expansions. You are expanding $* to get myexe1 directly (assuming for the moment that variable works the way you intended). You then prefix that with DEP_ and used $(DEP_$*) to get the lib1.lib lib2.lib. You then expand that result $($(DEP_$*)) and then expand that (empty) result again (to do your substitution) $($($(DEP_$*)):%=Lib\\%).
You want to either use $(#:.exe=) instead of $* in your rule body or use %.exe as your target and then use $* to get myexe1/myexe2.
You then want to drop two levels of expansion from $($($(DEP_$*)):%=Lib\\%) and use $(DEP_$*:%=Lib\\%) instead.
So (assuming you use the pattern rule) you end up with:
%.exe:
$(LINK) -OUT:"Exe\$#" -ADDOBJ:"Obj\$<" -IMPLIB:$(DEP_$*:%=Lib\\%)
I managed to get it working without needing to resolve macros in the way described above. I modified the linking dependencies like this;
myexe1.exe : myobj1.obj lib1.lib lib2.lib
myexe2.exe : myobj2.obj lib3.lib lib4.lib
Then I need to filter these files by extension in the target recipe;
$(EXEFILES):
$(LINK) -OUT:"$(EXE_PATH)\$#" -ADDOBJ:$(patsubst %, Obj\\%, $(filter %.obj, $^)) -IMPLIB:$(patsubst %, Lib\\%, $(filter %.lib, $^))
The $(pathsubst ...) is used to prepend the path that the relevant files are in.
In the case of myexe1.exe, the link command expands to;
slink -OUT:"Exe\myexe1.exe" -ADDOBJ: Obj\myexe1.obj -IMPLIB: Lib\lib1.lib Lib\lib2.lib
Out of interest's sake, I would still like to know if it is possible to resolve macro names like in the question.
How would I go about getting a list of available functions and their parameters in a given namespace?
http://code.kx.com/q/ref/syscmds/#f-functions
\f .
\f .namspace
For functions you will have to check parameters individually by just giving the name of function
.n.function
will give you not only the parameters but the whole function definition.
this can surely be improved upon, but thought I'd share as a quick way to get the ball rolling. This will retrieve every global user defined function in every workspace and create a dictionary of namespapaces to functions to parameters.
q)getparams:{k!{n[w]!#'[;1] value each f w:where 100h=type each f:get each ".",/:"." sv/:string x,/:n:y x}[;m] each key m:k!system each "f .",/:string k:key `}
q)f1:{x+y+z}
q).n1.f2:{x*x}
q).n1.a:2
q).n2.f3:{y+y}
q)show r:getparams[]
q | `aj`aj0`asc`asof`avgs`cols`cor`cov`cross`cut`desc`dev`each`ej`except`fby`..
Q | `Cf`IN`L`S`V`addmonths`bv`chk`cn`d0`dd`def`dpft`dpt`dsftg`dt`en`f`fc`ff`f..
h | `cd`code`data`eb`ec`ed`edsn`es`fram`ha`hb`hc`hn`hr`ht`hta`htac`htc`html`h..
n1| (,`f2)!,,`x
n2| (,`f3)!,`x`y
q)r[`n1;`f2]
,`x
[EDIT] the original function was wrong. It missed the global namespace (`) and didn't capture composition, or functions defined with an adverb. The below corrects this, but seems overly convoluted. I'll still leave it here though in case anyone wants to post a nicer solution (so that I too can learn from that)
getparams:{k!{n[w][w2]!#'[;1] v w2:where 0h=type each v:value/[{type[x] in y}[;t]; ] each f:f w:where in[ ;(t:"h"$100,105+til 7)] type each f:get each `$".",/:"." sv/:string x,/:n:y x}[;m] each key m:k!system each "f .",/:string k:`,key `}
I addition to Naveen's answer, you can call value functionName which will give you a list of items, e.g. parameter names and the compiled byte code