I'm trying to store my results in NSArray and save it as CSV File using Objective-C but i don't seem to find any solution which is relevant. Please find the below sample code:
int a=5,b=10;
int c=b-a;
double d=4.5,e=3.0;
double h=d-e;
NSLog(#"host_port:%f", c);
NSLog(#"host_size:%d", h;
I would like to store my values c and h in array and write that to CSV File. Any advise on this would be helpful.
Thanks in advance.
When you ask a question on SO you need to show effort - code you've tried, details of what you've read - if you don't you'll get down and close votes (you have one of each as I write this). The code you have included has nothing to do with CSV or arrays, and is not even pasted in valid code (the formats are wrong).
That said, let's see if you can give you something to get you going.
A CSV file is just plain text, you don't need to use any packages to write one, just standard I/O routines will do the job. You also do not need to store all the values in an array and then output the array, or build up a string version of the whole CSV file and output that, you can output items as they are generated if you wish and it may be more efficient to do so. In your code fragment you only have two values, maybe you intend this to be the core of a loop, and given those we assume you wish the CSV file:
host_port,host_size
5,1.5
your values have basic types, int and double, they are not Objective-C object types. Given this you can use the standard C I/O operations to produce your file.
First you may need to obtain the destination file name from the user, assuming this is a GUI app look up NSOpenPanel for this. That will give you an NSURL from which you can obtain the file path as an NSString, and you can convert that into a C string using NSString methods.
Now you can enter the C I/O world, to find the documentation on the following functions open the Terminal and use the man command, e.g. man fopen etc.
To create and open for writing the file for writing use fopen() passing it the C string pathname you obtained above.
To write the headers and each row of data use fprintf(). This takes a format string just like NSLog(), but you must remember to explicitly include the line breaks by using \n in the format.
When you've finished close the file with fclose().
Now go read the documentation and write your CSV file!
HTH
Related
Let's say you only want to parse the start of a large file using Perl 6 grammar. In order to avoid reading the whole file into a string, and then call subparse on the string. Is it possible to do a subparse when reading the file?
I could not find any subparsefile() method in the Grammar class, so I guess this is difficult to implement. But it should be possible in theory, see for example How do I search a file for a multiline pattern without reading the whole file into memory?
Currently you can't. Parsing anything at the moment requires the entire string to exist in memory.
Having said that, if you know the maximum number of lines your pattern may expand over, you could do something like:
my $max = 3; # maximum number of lines
for "textfile".IO.lines(:!chomp).rotor( $max => -$max + 1 ) -> #lines {
#lines.join.subparse( $grammar)
# and whatever you would like to do
}
It wouldn't be the fastest way of doing it, but it would not have to read the whole file in memory.
I write a code in python that detect malicious PDF.
every file I analyze I calculate its hash value and save it in hash database, besides saving the output in text file.
If I want to scan another file I calculated it hash value then search it in hash database, if found I print the output from the text that is already exist.
but if the hash value is not exist it is saved and the output is saved in text file
I need help on how could I link between the hash value and the text that contain the output?
As Kyle mentioned, you can use a hash table. A hash table is similar to a dictionary. In python I actually believe they're called dictionaries. For more on that, look here: http://www.tutorialspoint.com/python/python_dictionary.htm
As far as your question is concerned, you have a variety of options. You will have to save your 'database' at some point and you could save it in many different formats. You could save it as a JSON file (a very popular style). It could be an XML file (very popular as well). You could even save it as a CSV (not nearly as popular, but it gets the job done). For the sake of this, let's say you save this 'database' in a text file which looks like this:
5a4730fc12097346fdf5589166c373d3{C:\PdfsOutput\FileName.txt}662ad9b45e0f30333a433566cee8988d{C:\PdfsOutput\SomeOtherFile.txt}
Essentially you're formatting it as HashValue{PathToFileOnDisk}... You could then parse this via regex that looks like [0-9a-f]{32}\{[^\}]+ Then you would scan your database on startup using this regex, load up all matches, iterate all matches, split each match at '{' and then put the ValueSplit[0] into a dictionary as the key with the path to that text file as the value for that key.
So, after you do the regex search, get your matches and are iterating them, within the iteration loop say something like:
ValueSplit = RegexMatch.split('{')
HashAndFileDict[ValueSplit[0]] = ValueSplit[1]
This code assumes the regex match in the loop is a string simply called 'RegexMatch'. It also assumes that your dictionary you're storing hash values and paths in is called 'HashAndFileDict'
Later in your code you can check a PDF hash value in question by saying:
if(!HashAndFileDict.hash_key(PDFHashValue):
TextFilePath = savePDFOutputText(ThePDFFile)
HashAndFileDict[PDFHashValue] = TextFilePath
else:
print("File already processed. Text is at: " + HashAndFileDict[PDFHashValue])
If I may, it might be wise to use 2 hashing algorithms and combine their hexadecimal digests into 1 string in order to prevent a collision when processing many PDF files.
I've been trying to write a simple script compiler for a custom language used by the Game Boy Advance's Z80 processor.
All I want it to do is look at a human-readable command, take it and its arguments and convert it into a hexadecimal value into a ROM file. That's it. Each command is a byte, and each may take a different number of arguments - arguments can be either 8, 16, or 32 bits and each command has a specific number of arguments that it takes.
All of this sort of code is handled by the game and converted into workable machine code within the game's memory, so I'm not writing a full-on assembly compiler if you will. The game automatically knows how many args a command has, what each command does, exactly how to execute it as it is, etc.
For instance, you have command 0x4E, which takes in one 8-bit argument and another 32-bit argument. In hex that would obviously be 4E XX YY YY YY YY. I want my compiler to read it from text as foo 0xXX 0xYYYYYYYY and directly write it into a file as the former.
My question is, how would I do that in VB.NET? I know it's probably a very simple answer, but I see a lot of different options to write it to a file--some work and most don't for me. Could you give me some sample code as to how I would do this?
Writing an assembly compiler as I understand it is not so simple. I recomed you to use one already written see: Software Development Tools for Z80 Family
If you are still interested in writing it here are instructions:
Write the text you want to translate to some file (or memory stream)
Read it line by line
Parse the line either splitting it to an array or with regular
expressions
Identify command and arguments (as far as I remember it some commands
does not have arguments)
Translate the command to Hex (with a collection or dictionary of
commands)
Write results to an array remembering the references for jump
addresses
When everything is translated resolve addresses and write them to
right places.
I think that the most tricky part is to deal with symbolic addressees.
If you are still interested write a first piece of code (or ask how to do it) and continue with next ones.
This sounds like an assembler, even if it for a 'custom language'.
Start by parsing the command lines. use string.split method to convert the string to an array of strings. the first element in the array is your foo, you can then look that up and output 4E, then convert the subsequent elements to bytes.
I am looking for ways to read in a PDF file with SAS. Apparently this is not basic functionality and there is very little to be found on the internet. (Let alone that google is not easy with PDF in you search giving you also links to PDF documents that go about other things.)
The only things that can be found, are people looking for ways to import data into datasets from a PDF. For me, that is not even necesarry. I would like to be able to read the contents of the PDF file in one big character variable. If possible, it would even be better to be able to read in the file's binary data.
Is this possible with SAS and how? (I got it to work in Access VBA, but can't find any similar ways in SAS.)
(In the end, the purpose is to convert this to base64 and put that base64-string into an XML document.)
You probably will not be able to read the entire file into one character variable since the maximum size of a character variable is around 33 KB. A simple way to read in one line at a time, though, is something like the following:
%let pdfFileName = Test.pdf;
%let lineSize = 2000;
data base;
format text_line $&lineSize..;
infile "&pdfFileName" lrecl=&lineSize;
input text_line $;
run;
This requires that you have a general idea of the maximum record length ahead of time, but you could write additional code to determine the maximum record size prior to reading in the file. In this example each line of text is read into one character variable named "text_line." From there, you could use a RETAIN statement or double trailers (##) in the INPUT line to process multiple lines at a time. The SAS web-site has plenty of documentation on how to read and process text from various types of input files.
I'm trying to open an existent file save a bytes in the start of it to later read them.
How can I do that? Because the "&" operand isn't working fo this type of data.
I'm using Encoding.UTF8.GetBytes("text") to convert info to bytes and then add them.
Help Please.
You cannot add to or remove from the beginning of a file. It just doesn’t work. Instead, you need to read the whole file, and then write a new file with the modified data. (You can, however, replace individual bytes or chunks of bytes in a file without needing to touch the whole file.)
Secondly,
I'm using Encoding.UTF8.GetBytes("text") to convert info to bytes and then add them.
You’re doing something wrong. Apparently you’ve read text data from the file and are now trying to convert it to bytes. This is the wrong way of doing it. Do not read text from the file, read the bytes directly (e.g. via My.Computer.FileSystem.ReadAllBytes). Raw byte data and text (i.e. String) are two fundamentally different concepts, do not confuse them. Do not convert needlessly to and fro.