Pls help me
A few weeks ago it came out of gamemaker 2.3, practically in the gamemaker language they changed the scripts into functions, but now after converting the files to be able to reopen them, I double-checked all the scripts and etc but anyway when I start it it remains a black screen, however it doesn't give me any compilation errors or whatever, what could be the problem?
Ps.
I might sound stupid, but if someone has the same program as me I can pass the project to them so they can see the scripts for themselves, so basically it's just the base and there is only the script to make the player walk and for collisions, I know that no one would want to waste time, but I ask the same
Its possible that your code is stuck in an infinite loop, here's an example of what that might look like:
var doloop = true
while(doloop == true){
x += 1
y += 1
}
the "doloop" variable is never changed within the while loop, so it is always equal to true and the loop never ends. Because the code never finishes looping, it can never get around to drawing anything, so you end up with a black screen. The easiest way to check for these is to put a breakpoint/debugging point at the beginning and just after every while/for/do/ect loop and debug it. e.g. (I am using asterisks "*" to represent breakpoints)
var doloop = true
* while(doloop == true){
x += 1
y += 1
}
*
When you get to one of the loops remove the first breakpoint and hit the "continue" button in the debugger. If it (it being the computer) takes an longer than it should to hit the second breakpoint (as in, you wait for a ten seconds to or two minutes (depends on how complex the code is) and it still hasn't hit the second breakpoint), then you should replace the breakpoint at the beginning of the loop to check and make sure it is still in there. If it is still in the loop, then that is likely where the code is getting stuck. Review the loop and everywhere any associated variables are set/changed, and you should be able to find the problem (even if it takes a while).
Majestic_Monkey_ and the commentors are correct: use the debugger. It's easy and it's your friend. Just place a red circle on the very first line of code that runs, and click the little bug icon and you can step through your code easily.
But to address your specific issue (or if anyone in the future has this issue): scripts have changed into files that can have many functions. Where you used to have
//script_name
var num = argument0 + argument1;
return num;
You would now have
function script_name(a, b) {
var num = a + b;
return num;
}
All you have to do is create a decleration for your new function:
function my_function_name(argument_names, etc...)
Then wrap all your old code in { }, and replace all those ugly "argument0" things with actual names. It's that easy. Plus you can have more than one function per script!
I am new to sage and have got a code (link to code) which should run.
I am still getting an error message in the decoding part. The error trace looks like this:
in decode(y)
--> sigma[i+1+1] = sigma[i+1]*(z)\
-(delta[i+1]/delta[mu+1])*z^(i-mu)*sigma[mu+1]*(z);
in sage.structure.element.Element.__mul__
if BOTH_ARE_ELEMNT(cl):
--> return coercion_model.bin_op(left, right, mul)
in sage.structure.coerce.CoercionModel_cache_maps.bin_op
--> action = self.get_action(xp,yp,op,x,y)
...... some more traces (don't actually know if they are important)
TypeError: positive characteristics not allowed in symbolic computations
Does anybody know if there is something wrong in this code snipped? Due to previous errors, I changed the following to get to where I am at the moment:
.coeffs() changed to .coefficients(sparse=False) due to a warning message.
in the code line sigma[i+1+1] = sigma[i+1](z)\
-(delta[i+1]/delta[mu+1])*z^(i-mu)*sigma[mu+1](z); where the error occurs, i needed to insert * eg. sigma[i+1]*(z)
I would be grateful for any guess what could be wrong!
Your issue is that you are multiplying things not of characteristic zero (like elements related to Phi.<x> = GF(2^m)) with elements of symbolic computation like z which you have explicitly defined as a symbolic variable
Phi.<x> = GF(2^m)
PR = PolynomialRing(Phi,'z')
z = var('z')
Basically, the z you get from PR is not the same one as from var('z'). I recommend naming it something else. You should be able to access this with PR.gen() or maybe PR(z).
I'd be able to be more detailed, but I encourage you next time to paste a fully (non-)working example; trying to slog through a big worksheet is not the easiest thing to track all this down. Finally, good luck, hope Sage ends up being useful for you!
I am a beginner to programming. I am trying to run a simulation of a combustion chamber using reactingFoam.
I have modified the counterflow2D tutorial.
For those who maybe don't know OpenFOAM, it is a programme built in C++ but it does not require C++ programming, just well-defining the variables in the files needed.
In one of my first tries I have made a very simple model but since I wanted to check it very well I set it to 60 seconds with a 1e-6 timestep.
My computer is not very powerful so it took me for a day aprox. (by this I mean I'd like to find a solution rather than repeating the simulation).
I executed the solver reactingFOAM using 4 processors in parallel using
mpirun -np 4 reactingFOAM -parallel > log
The log does not show any evidence of error.
The problem is that when I use reconstructPar it works perfectly but then I try to watch the results with paraFoam and this error is shown:
From function bool Foam::IOobject::readHeader(Foam::Istream&)
in file db/IOobject/IOobjectReadHeader.C at line 88
Reading "mypath/constant/reactions" at line 1
First token could not be read or is not the keyword 'FoamFile'
I have read that maybe some files are empty when they are not supposed to be so, but I have not found that problem.
My 'reactions' file have not been modified from the tutorial and has always worked.
edit:
Sorry for the vague question. I have modified it a bit.
A typical OpenFOAM dictionary file always contains a Foam::Istream named FoamFile. An example from a typical system/controlDict file can be seen below:
FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "system";
object controlDict;
}
During the construction of the dictionary header, if this Istream is absent, OpenFOAM ceases its operation by raising an error message that you have experienced:
First token could not be read or is not the keyword 'FoamFile'
The benefit of the header is possibly to contribute OpenFOAM's abstraction mechanisms, which would be difficult otherwise.
As mentioned in the comments, adding the header entity almost always solves this problem.
I wonder if there is a way to display the current time in the R command line, like in MS DOS, we can use
Prompt $T $P$G
to include the time clock in every prompt line.
Something like
options(prompt=paste(format(Sys.time(), "%H:%M:%S"),"> "))
will do it, but then it is fixed at the time it was set. I'm not sure how to make it update automatically.
Chase points the right way as options("prompt"=...) can be used for this. But his solutions adds a constant time expression which is not what we want.
The documentation for the function taskCallbackManager has the rest:
R> h <- taskCallbackManager()
R> h$add(function(expr, value, ok, visible) {
+ options("prompt"=format(Sys.time(), "%H:%M:%S> "));
+ return(TRUE) },
+ name = "simpleHandler")
[1] "simpleHandler"
07:25:42> a <- 2
07:25:48>
We register a callback that gets evaluated after each command completes. That does the trick. More fancy documentation is in this document from the R developer site.
None of the other methods, which are based on callbacks, will update the prompt unless a top-level command is executed. So, pressing return in the console will not create a change. Such is the nature of R's standard callback handling.
If you install the tcltk2 package, you can set up a task scheduler that changes the option() as follows:
library(tcltk2)
tclTaskSchedule(1000, {options(prompt=paste(Sys.time(),"> "))}, id = "ticktock", redo = TRUE)
Voila, something like the MS DOS prompt.
NB: Inspiration came from this answer.
Note 1: The wait time (1000 in this case) refers to the # of milliseconds, not seconds. You might adjust it downward when sub-second resolution is somehow useful.
Here is an alternative callback solution:
updatePrompt <- function(...) {options(prompt=paste(Sys.time(),"> ")); return(TRUE)}
addTaskCallback(updatePrompt)
This works the same as Dirk's method, but the syntax is a bit simpler to me.
You can change the default character that is displayed through the options() command. You may want to try something like this:
options(prompt = paste(Sys.time(), ">"))
Check out the help page for ?options for a full list of things you can set. It is a very useful thing to know about!
Assuming this is something you want to do for every R session, consider moving that to your .Rprofile. Several other good nuggets of programming happiness can be found hither on that topic.
I don't know of a native R function for doing this, but I know R has interfaces with other languages that do have system time commands. Maybe this is an option?
Thierry mentioned system.time() and there is also proc.time() depending on what you need it for, although neither of these give you the current time.
I am making a C application in Unix that uses raw tty input.
I am calling write() to characters on the display, but I want to manipulate the cursor:
ssize_t
write(int d, const void *buf, size_t nbytes);
I've noticed that if buf has the value 8 (I mean char tmp = 8, then passing &tmp), it will move the cursor/pointer backward on the screen.
I was wondering where I could find all the codes, for example, I wish to move the cursor forward but I cannot seem to find it via Google.
Is there a page that lists all the code for the write() function please?
Thank you very much,
Jary
8 is just the ascii code for backspace. You can type man ascii and look at all the values (the man page on my Ubuntu box has friendlier names for the values). If you want to do more complicated things you may want to look at a library like ncurses.
You have just discovered that character code 8 is backspace (control-H).
You would probably be best off using the curses library to manage the screen. However, you can find out what control sequences curses knows about by using infocmp to decompile the terminfo entry for your terminal. The format isn't particularly easy to understand, but it is relatively comprehensive. The alternative is to find a manual for the terminal, which tends to be rather hard.
For instance, I'm using a color Xterm window; infocmp says:
# Reconstructed via infocmp from file: /usr/share/terminfo/78/xterm-color
xterm-color|nxterm|generic color xterm,
am, km, mir, msgr, xenl,
colors#8, cols#80, it#8, lines#24, ncv#, pairs#64,
acsc=``aaffggiijjkkllmmnnooppqqrrssttuuvvwwxxyyzz{{||}}~~,
bel=^G, bold=\E[1m, clear=\E[H\E[2J, cr=^M,
csr=\E[%i%p1%d;%p2%dr, cub=\E[%p1%dD, cub1=^H,
cud=\E[%p1%dB, cud1=^J, cuf=\E[%p1%dC, cuf1=\E[C,
cup=\E[%i%p1%d;%p2%dH, cuu=\E[%p1%dA, cuu1=\E[A,
dch=\E[%p1%dP, dch1=\E[P, dl=\E[%p1%dM, dl1=\E[M, ed=\E[J,
el=\E[K, enacs=\E)0, home=\E[H, ht=^I, hts=\EH, il=\E[%p1%dL,
il1=\E[L, ind=^J,
is2=\E[m\E[?7h\E[4l\E>\E7\E[r\E[?1;3;4;6l\E8, kbs=^H,
kcub1=\EOD, kcud1=\EOB, kcuf1=\EOC, kcuu1=\EOA,
kdch1=\E[3~, kf1=\E[11~, kf10=\E[21~, kf11=\E[23~,
kf12=\E[24~, kf13=\E[25~, kf14=\E[26~, kf15=\E[28~,
kf16=\E[29~, kf17=\E[31~, kf18=\E[32~, kf19=\E[33~,
kf2=\E[12~, kf20=\E[34~, kf3=\E[13~, kf4=\E[14~,
kf5=\E[15~, kf6=\E[17~, kf7=\E[18~, kf8=\E[19~, kf9=\E[20~,
kfnd=\E[1~, kich1=\E[2~, kmous=\E[M, knp=\E[6~, kpp=\E[5~,
kslt=\E[4~, meml=\El, memu=\Em, op=\E[m, rc=\E8, rev=\E[7m,
ri=\EM, rmacs=^O, rmcup=\E[2J\E[?47l\E8, rmir=\E[4l,
rmkx=\E[?1l\E>, rmso=\E[m, rmul=\E[m,
rs2=\E[m\E[?7h\E[4l\E>\E7\E[r\E[?1;3;4;6l\E8, sc=\E7,
setab=\E[4%p1%dm, setaf=\E[3%p1%dm, sgr0=\E[m, smacs=^N,
smcup=\E7\E[?47h, smir=\E[4h, smkx=\E[?1h\E=, smso=\E[7m,
smul=\E[4m, tbc=\E[3g, u6=\E[%i%d;%dR, u7=\E[6n,
u8=\E[?1;2c, u9=\E[c,
That contains information about box drawing characters, code sequences generated by function keys, various cursor movement sequences, and so on.
You can find out more about X/Open Curses (v4.2) in HTML. However, that is officially obsolete, superseded by X/Open Curses v7, which you can download for free in PDF.
If you're using write just so you have low-level cursor control, I think you are using the wrong tool for the job. There are command codes for many types of terminal. VT100 codes, for example, are sequences of the form "\x1b[...", but rather than sending raw codes, you'd be much better off using a library like ncurses.