I am using a loop that adds a value (step) to dist. After adding step to dist I would like to use it in the following calculation which provides the value c. Both, dist and c, should then be listed in two columns next to each other in an output file.
If I use the code below it works at least to list the values for dist in the output file.
dist=0
do while (dist < rim)
dist=dist+step
c=0.5*(cl-cr)*erfc((dist)/(2*sqrt(t*d)))+cr
write(1,'(1f20.0)')dist*1E+06
enddo
If I replace the write command by the one below it will not list two nice columns but somehow mix both.
write(1,'(1f20.0,1f15.5)')dist*1E+06,c
Is this a problem related to the positioning of the writing command in the loop or is it related to the format it is told to write the values?
You should add a space between them and re-check:
write(*,'(F20.0,1X,F15.5)') dist*1E+06, c
Also consider the accuracy with which you are writing the results to the file.
Related
I'm trying to split some datasets in two parts, running a loop over files like this:
cd C:\Users\Macrina\Documents\exports
qui fs *
foreach f in `r(files)' {
use `r(files)'
keep id adv*
save adv_spa*.dta
clear
use `r(files)'
drop adv*
save fin_spa*.dta
}
I don't know whether what is inside the loop is correctly written but the point is that I get the error:
invalid '"e2.dta'
where e2.dta is the second file in the folder. Does this message refer to the loop or maybe what is inside the loop? Where is the mistake?
You want lines like
use "`f'"
not
use `r(files)'
given that fs (installed from SSC, as you should explain) returns r(files) as a list of all the files whereas you want to use each one in turn (not all at once).
The error message was informative: use is puzzled by the second filename it sees (as only one filename makes sense). The other filenames are ignored: use fails as soon as something is evidently wrong.
Incidentally, note that putting "" around filenames remains essential if any includes spaces.
I'm very new to matlab, or coding for that matter.
I'm running a simulation which outputs thousands of files. These files are .vtk and are read correctly by dlmread.
I tried reading one of them, defining it as a matrix and extracting column vectors out of this matrix. This works fine. What i need now is to not only read one of them, but all. The filenames vary by a number, for example cover1000.vtk, cover2000.vtk, ...., cover1200000.vtk.
I want all of them to be read with dlmread and stored as a different matrix. How do i do that? Here is what i have right now, working with one file at a time:
A_1000 = dlmread ('cover1000.vtk') %matrix a containing values from vtk file_in_loadpath
fx_1000 = A(1:20,1) %extracting vector with specific values
fx_ave_1000 = sum(fx_1000)/length(fx_1000) % average of the values in extracted vector
I'm thinking of a loop, but how do i create a loop with varying file names?
Also I've read that a loop is not the best idea, cell arrays would be better. But i have absolutely no idea how to implement any of this.
Thanks for your help!
cheers
You can use the function dir to list all the vtk files in your directory then loop over those files.
filename = dir('*.vtk'); %list all the vtk files in your current directory.
for ii = 1:length(filename)
A = dlmread (filename(ii).name) %matrix a containing values from vtk file_in_loadpath
fx{ii} = A(1:20,1) %extracting vector with specific value
fx_ave{ii} = sum(fx{ii})/length(fx{ii}) % average of the values in extracted vector
end
The results are now stored in two cells: fx and fx_ave.
I have several datasets over which i want to run identical commands.
My basic idea is to create a vector with the names of the datasets and loop over it, using the specified name in my GET command:
VECTOR=(9) D = Name1 to Name9.
LOOP #i = 1 to 9.
GET
FILE = Directory\D(#i).sav
VALUE LABELS V1 to V8 'some text D(#i)'
LOOP END.
Now SPSS doesn't recognize that i want it to use the specific value of the vector D.
In Stata i'd use
local D(V1 to V8)
foreach D{
....`D' .....
}
You can't use VECTOR in this way i.e. using GET command within a VECTOR/LOOP loop.
However you can use DEFINE/!ENDDEFINE. This is SPSS's native macro facility language, if you are not aware of this, you'll most likely need to do a lot of reading on it and understand it's syntax usage.
Here's an example:
DEFINE !RunJob ()
!DO !i !IN 1 !TO 9
GET FILE = !CONCAT("Directory\D(",#i,").sav").
VALUE LABELS V1 to V8 !QUOTE(!ONCAT("some text D(",#i,")",
!DOEND
!ENDDEFINE.
SET MPRINT ON.
!RunJob.
SET MPRINT OFF.
All the code between DEFINE and !ENDDEFINE is the body of the macro and the syntax near to the end !RunJob. then runs and executes those procedures defined in the macro.
This a very simply use of a macro with no parameters/arguments assigned but there is scope for much more complexity.
If you are new to DEFINE/!ENDEFINE I would actually suggest you NOT invest time in learning this but instead learn Python Program ability which can be used to achieve the same (and much more) with relative ease compared to DEFINE/!ENDDEFINE.
A python solution to your example would look like this (you will need Python Programmability integration with your SPSS):
BEGIN PROGRAM.
for i in xrange(1,9+1):
spss.Submit("""
GET FILE = Directory\D(%(i)s).sav
VALUE LABELS V1 to V8 'some text D(%(i)s)'.""" % locals())
END PROGRAM.
As you will notice there is much more simplicity to the python solution.
#Caspar: use Python for SPSS for such jobs. SPSS macros have been long deprecated and had better be avoided.
If you use Python for this, you don't even have to type in the file names: you can simply look up all file names in some folder that end with ".sav" as shown in this example.
HTH!
The Python approach is as Ruben says much superior to the old macro facility, but you can use the SPSSINC PROCESS FILES extension command to do tasks like this without any need to know Python. PROCESS FILES is included in the Python Essentials in recent versions of Statistics but can be downloaded from the SPSS Community website (www.ibm.com/developerworks/spssdevcentral) in older versions.
The idea is that you create a syntax file that works on one data file, and PROCESS FILES iterates that over a list of input files or a wildcard specification. For each file, it defines file handles and macros that you can use in the syntax file to open and process the data.
I'm trying to get an array containing the full current directory path in zsh. I'm currently using
local pwd="${PWD/#$HOME/~}"
pwd_list=(${(s:/:)pwd})
Which works except for one problem, it treats the starting / as a directory split too. I'd like my array to be like
/
usr
lib
php
instead of
usr
lib
php
I can see 2 ways of doing this but I'm unaware of how to do either in zsh. The first idea is to simple do a push and force a new element to the beginning (after the split).
The second, would be to alter the split to ignore the first / when parsing.
How can I resolve this to get an accurate directory path with minimal overhead into an array?
do you really need the first /? Assuming you're using a script to use the results of that, can't you just cd / to just start from there?
Anyways... is this what you want?
local pwd="${PWD/#$HOME/~}"
pwd_list=(${(s:/:)pwd})
pwd_list=('/' $pwd_list)
I think you're thinking about it slightly wrong. If you split "/usr/lib/php" on "/", you should get four elements, the first of which is an empty string. If you join those array elements back together with "/", you get the original path. Trying to think of the first element of "/" means you're treating the splitting inconsistently, which will make everything else harder.
So the problem really is that you're only getting three elements instead of four: the empty first element is getting dropped. You can fix that by quoting, like this:
local pwd="${PWD/#$HOME/~}"
pwd_list=( "${(s:/:)pwd}" )
(The extra space next to the outer parentheses isn't necessary, but it makes it a little easier to read.) You can even combine that into one expression:
pwd_list=( "${(s:/:)${PWD/#$HOME/~}}" )
How can I create a function with MATLAB so I can call it any where in my code?
I'm new to MATLAB so I will write a PHP example of the code I want to write in MATLAB!
Function newmatlab(n){
n=n+1;
return n;
}
array=array('1','2','3','4');
foreach($array as $x){
$result[]=newmatlab($x);
}
print_f($result);
So in nutshell, I need to loop an array and apply a function to each item in this array.
Can some one show me the above function written in MATLAB so I can understand better?
Note: I need this because I wrote a code that analyzes a video file and then plots data on a graph. I then and save this graph into Excel and jpg. My problem is that I have more than 200 video to analyze, so I need to automate this code to loop inside folders and analyze each *.avi file inside and etc.
As others have said, the documentation covers this pretty thoroughly, but perhaps we can help you understand.
There are a handful of ways that you can define functions in Matlab, but probably the most useful for you to get started is to define one in an m-file. I'll use your example code. You can do this by creating a file called newmatlab.m in your project's directory that looks something like this
% newmatlab.m
function result = newmatlab(array)
result = array + 1
Note that the function has the same name as the file and that there is no explicit return statement - it figures that out by what you've named the output parameter(s) (result in this case).
Then, in the same directory, you can create a script (or another function) that calls your newmatlab function by that name:
% main.m (or whatever)
a = [1 2 3 4];
b = newmatlab(a)
That's it! This is a simplified explanation, but hopefully enough to get you started and then the documentation can help more.
PS: There's no "include" in Matlab; any functions that are defined in m-files in the current path are visible. You can find out what's in the path by using the path command. Roughly, it's going to consist of
Matlab's own directory
The MATLAB subdirectory of your Documents directory
The current working directory