I am trying to read data using Cobol with following the restriction
NOT allowed to use :
AT END clause
PERFORM-UNTIL
IF-ELSE
Switch case statement
Iteration Statement
002-READ.
READ d-attendance
IF (?????)
perform 002-READ
END-IF.
I am trying to simulate a loop with code above but i don't know how I should write the IF statement, is there any way to detect EOF without using AT END?
When you first define your file under file-control, you can define it like this:
select my-file
assign to 'ifile.txt'
organization is line sequential
file status is fs.
now, fs variable's value changes when you read from the file. For instance, when no errors are found, fs takes the value 00. More information can be found here.
If you are not allowed to use such statements that you have listed, then you can call your function that reads a line recursively until fs is not equal to 00.
Related
The following is my sample code: https://play.openpolicyagent.org/p/oyY1GOsYaf
Here when I try to evaluate names array, it is showing:
error occurred: 1:1: rego_unsafe_var_error: var names is unsafe
But when I define the same comprehension outside the allow rule definition : https://play.openpolicyagent.org/p/Xv0cF7FM8b, I am able to evaluate the selection
[
"smoke",
"dev"]
could someone help me to point out the difference and if I want to define the comprehention inside the rule is there any syntax I need to follow? Thanks in advance
Note: I am getting the final output as expected in both cases, only issue is with the names array evaluation.
The way the Rego Playground generates a query when evaluating a selection is much more simplistic than one might assume. A query will be generated from your selected text, without taking into account where in the document that text was selected. This means that even if you select a local variable inside a rule body, the query will simply contain that variable name (names, in your case); which will be perceived as a reference to a top-level variable in the document's body, even though a rule-local variable was selected. This is why your first sample returns an error, as there is no top-level variable names in the document; whereas the second sample does, and therefore succeeds.
You can test this quirk by selecting and evaluating the word hello on line 3 here: https://play.openpolicyagent.org/p/n5OPoFnlhx.
package play
# hello
hello {
m := input.message
m == "world"
}
Even though it's just part of a comment, it'll evaluate just as if you had selected the rule name on line 5.
I am trying to use a program to speed up a repetitive Stata task. This is the first part of my program:
program alphaoj
syntax [varlist] , using(string) occ_level(integer) ind_level(integer)
import excel `using', firstrow
display "`using'"
split "`using'", parse(_)
local year = `2'
display "`year'"
display `year'
When I run this program, using the line alphaoj, ind_level(4) occ_level(5) using("nat4d_2002_dl.xls"), I receive the error factor-variable and time-series operators not allowed r(101);
I am not quite sure what is being treated as a factor or time series operator.
I have replaced the split line with tokenize, and the parse statement with parse("_"), and I continue to run into errors. In that case, it says _ not found r(111);
Ideally, I would have it take the year from the filename and use that year as the local.
I am struggling with how I should perform this seemingly simple task.
An error is returned because the split command only accepts string variables. You can't pass a string directly to it. See help split for more details.
You can achieve your goal of extracting the year from the filename and storing that as a local macro. See below:
program alphaoj
syntax [varlist], using(string)
import excel `using', firstrow
gen stringvar = "`using'"
split stringvar, parse(_)
local year = stringvar2
display `year'
end
alphaoj, using("nat4d_2002_dl.xls")
The last line prints "2002" to the console.
Alternative solution that avoids creating an extra variable:
program alphaoj
syntax [varlist], using(string)
import excel `using', firstrow
local year = substr("`using'",7,4)
di `year'
end
alphaoj, using("nat4d_2002_dl.xls")
Please note that this solution is reliant on the Excel files all having the exact same character structure.
I am following instructions from this link on how to append Stata files via a foreach loop. I think that it's pretty straightforward.
However, when I try to refer to each f in datafiles in my foreach loop, I receive the error:
invalid `
I've set my working directory and the data is in a subfolder called csvfiles. I am trying to call each file f in the csvfiles subfolder using my local macro datafiles and then append each file to an aggregate Stata dataset called data.dta.
I've included the code from my do file below:
clear
local datafiles: dir "csvfiles" files "*.csv"
foreach f of local datafiles {
preserve
insheet using “csvfiles\`f'”, clear
** add syntax here to run on each file**
save temp, replace
restore
append using temp
}
rm temp
save data.dta, replace
The backslash character has meaning to Stata: it will prevent the interpretation of any following character that has a special meaning to Stata, in particular the left single quote character
`
will not be interpreted as indicating a reference to a macro.
But all is not lost: Stata will allow you to use the forward slash character in path names on any operating system, and on Windows will take care of doing what must be done to appease Windows. Replacing your insheet command with
insheet using “csvfiles/`f'”, clear
should solve your problem.
Note that the instructions you linked to do exactly that; some of the code includes backslashes in path names, but where a macro is included, forward slashes are used instead.
I'm having a hard time finding the documentation for this. How do I read/write text from the current buffer in my vim functions?
More concretely, if my buffer contains the words foo bar how would write a function to overwrite the word bar with cat so that in the end my buffer contains foo cat?
You can use the substitute ex command inside a function. For example
function! ReplaceBar()
:%s/bar/cat/g
endfunction
This defines a function. The % character means operate on the entire buffer. This searches for bar, replaces it with cat, and the g flag replaces every instance on a line, not just the first.
You can run this function by typing :call ReplaceBar() and hitting enter. Often it's convenient to define a function that does this kind of work, then define a command that calls it:
command! -nargs=0 Bar call ReplaceBar()
That command can be run by typing :Bar.
To access line(s), you can use the getline() function. setline() updates those lines in the buffer. Likewise, new lines are inserted via append().
The latter can also be done with :put ={variable or expression}, and replacements with :substitute. What is better depends on the particular use case. The benefit of the former, lower-level functions is that they don't clobber stuff like the expression register, last used search pattern, search history, etc.
In neovim, they have nvim_put. A few examples:
:call nvim_put(['cat'], 'c', v:false, v:true) ; insert 'cat' right where the cursor is, as if you typed `:normal! icat`
:call nvim_put(['cat'], 'l', v:true, v:true) ; insert 'cat' on the next line
Others have covered the use of :put pretty well, so I won't cover it myself.
I am relatively new to maxima. I want to know how to write an array into a text file using maxima.
I know it's late in the game for the original post, but I'll leave this here in case someone finds it in a search.
Let A be a Lisp array, Maxima array, matrix, list, or nested list. Then:
write_data (A, "some_file.data");
Let S be an ouput stream (created by openw or opena). Then:
write_data (A, S);
Entering ?? numericalio at the input prompt, or ?? write_ or ?? read_, will show some info about this function and related ones.
I've never used maxima (or even heard of it), but a little Google searching out of curiousity turned up this: http://arachnoid.com/maxima/files_functions.html
From what I can gather, you should be able to do something like this:
stringout("my_new_file.txt",values);
It says the second parameter to the stringout function can be one or more of these:
input: all user entries since the beginning of the session.
values: all user variable and array assignments.
functions: all user-defined functions (including functions defined within any loaded packages).
all: all of the above. Such a list is normally useful only for editing and extraction of useful sections.
So by passing values it should save your array assignments to file.
A bit more necroposting, as google leads here, but I haven't found it useful enough. I've needed to export it as following:
-0.8000,-0.8000,-0.2422,-0.242
-0.7942,-0.7942,-0.2387,-0.239
-0.7776,-0.7776,-0.2285,-0.228
-0.7514,-0.7514,-0.2124,-0.212
-0.7168,-0.7168,-0.1912,-0.191
-0.6750,-0.6750,-0.1655,-0.166
-0.6272,-0.6272,-0.1362,-0.136
-0.5746,-0.5746,-0.1039,-0.104
So I've found how to do this with printf:
with_stdout(filename, for i:1 thru length(z_points) do
printf (true,"~,4f,~,4f,~,4f,~,3f~%",bot_points[i],bot_points[i],top_points[i],top_points[i]));
A bit cleaner variation on the #ProdoElmit's answer:
list : [1,2,3,4,5]$
with_stdout("file.txt", apply(print, list))$
/* 1 2 3 4 5 is then what appears in file.txt */
Here the trick with apply is needed as you probably don't want to have square brackets in your output, as is produced by print(list).
For a matrix to be printed out, I would have done the following:
m : matrix([1,2],[3,4])$
with_stdout("file.txt", for row in args(m) do apply(print, row))$
/* 1 2
3 4
is what you then have in file.txt */
Note that in my solution the values are separated with spaces and the format of your values is fixed to that provided by print. Another caveat is that there is a limit on the number of function parameters: for example, for me (GCL 2.6.12) my method does not work if length(list) > 64.