using array names in tcl to get the indices matching regexp - arrays

Following array is set in tcl
db(PR,) =
db(PR,132754) = 5 6 7 8 9 10 11 12 13 14 31 32 33 34 35 36 37 38 39 40
db(PR,144917) = 2 3 28 29
db(PR,83055) = 4 30
I want all the array indices except db(PR,) since it has nothing after comma
I tried:
array names db -regexp PR,\d+
but it gives no output
and
array names db -regexp PR,*
PR,144917 PR,132754 PR, PR,83055
return unwanted PR, index
So how can i eliminate that array index from getting in array names output?

What about
array names db -regexp PR,.+
?
Resp.: If there are always digits after the comma (except for db(PR,)) you should escape the backslash
array names db -regexp PR,\\d+
or do
array names db -regexp PR,\[0-9]+

If the criterion is simply "must be something after the comma", it can be as simple as
array names db -regexp ,.
array names db -glob *,?* ;# alternative

Related

How do I split a string in groups of 2 characters in powershell without delimiters?

I have a problem where I accept a string of number. I need to split the string into group of 2 numbers and perform arithmetic operations on them. I am aware of powershell -split operator but it doesen't work as intended. Preferably I would like them to be split into array of 2 characters or integers.
Example:
$inputdata=1234302392323
Output:
12
34
30
23
92
32
3
You can use the split operator for this, and cast the array elements to int like:
[int[]]$result = '1234302392323' -split '(..)' -ne ''
$result will be an array of ints:
12
34
30
23
92
32
3

Multi-Dimensional Arrays Julia

I am new to using Julia and have little experience with the language. I am trying to understand how multi-dimensional arrays work in it and how to access the array at the different dimensions. The documentation confuses me, so maybe someone here can explain it better.
I created an array (m = Array{Int64}(6,3)) and am trying to access the different parts of that array. Clearly I am understanding it wrong so any help in general about Arrays/Multi-Dimensional Arrays would help.
Thanks
Edit I am trying to read a file in that has the contents
58 129 10
58 129 7
25 56 10
24 125 25
24 125 15
13 41 10
0
The purpose of the project is to take these fractions (58/129) and round the fractions using farey sequence. The last number in the row is what both numbers need to be below. Currently, I am not looking for help on how to do the problem, just how to create a multidimensional array with all the numbers except the last row (0). My trouble is how to put the numbers into the array after I have created it.
So I want m[0][0] = 58, so on. I'm not sure how syntax works for this and the manual is confusing. Hopefully this is enough information.
Julia's arrays are not lists-of-lists or arrays of pointers. They are a single container, with elements arranged in a rectangular shape. As such, you do not access successive dimensions with repeated indexing calls like m[j][i] — instead you use one indexing call with multiple indices: m[i, j].
If you trim off that last 0 in your file, you can just use the built-in readdlm to load that file into a matrix. I've copied those first six rows into my clipboard to make it a bit easier to follow here:
julia> str = clipboard()
"58 129 10\n58 129 7\n25 56 10\n24 125 25\n24 125 15\n13 41 10"
julia> readdlm(IOBuffer(str), Int) # or readdlm("path/to/trimmed/file", Int)
6×3 Array{Int64,2}:
58 129 10
58 129 7
25 56 10
24 125 25
24 125 15
13 41 10
That's not very helpful in teaching you how Julia's arrays work, though. Constructing an array like m = Array{Int64}(6,3) creates an uninitialized matrix with 18 elements arranged in 6 rows and 3 columns. It's a bit easier to see how things work if we fill it with a sensible pattern:
julia> m .= [10,20,30,40,50,60] .+ [1 2 3]
6×3 Array{Int64,2}:
11 12 13
21 22 23
31 32 33
41 42 43
51 52 53
61 62 63
This has set up the values of the array to have the row number in their tens place and the column number in the ones place. Accessing m[r,c] returns the value in m at row r and column c.
julia> m[2,3] # second row, third column
23
Now, r and c don't have to be integers — they can also be vectors of integers to select multiple rows or columns:
julia> m[[2,3,4],[1,2]] # Selects rows 2, 3, and 4 across columns 1 and 2
3×2 Array{Int64,2}:
21 22
31 32
41 42
Of course ranges like 2:4 are just vectors themselves, so you can more easily and efficiently write that example as m[2:4, 1:2]. A : by itself is a shorthand for a vector of all the indices within the dimension it indexes into:
julia> m[1, :] # the first row of all columns
3-element Array{Int64,1}:
11
12
13
julia> m[:, 1] # all rows of the first column
6-element Array{Int64,1}:
11
21
31
41
51
61
Finally, note that Julia's Array is column-major and arranged contiguously in memory. This means that if you just use one index, like m[2], you're just going to walk down that first column. As a special extension, we support what's commonly referred to as "linear indexing", where we allow that single index to span into the higher dimensions. So m[7] accesses the 7th contiguous element, wrapping around into the first row of the second column:
julia> m[5],m[6],m[7],m[8]
(51, 61, 12, 22)

How to identify breaks within an array of MATLAB?

I have an array in MATLAB containing elements such as
A=[12 13 14 15 30 31 32 33 58 59 60];
How can I identify breaks in values of data? For example, the above data exhibits breaks at elements 15 and 33. The elements are arranged in ascending order and have an increment of one. How can I identify the location of breaks of this pattern in an array? I have achieved this using a for and if statement (code below). Is there a better method to do so?
count=0;
for i=1:numel(A)-1
if(A(i+1)==A(i)+1)
continue;
else
count=count+1;
q(count)=i;
end
end
Good time to use diff and find those neighbouring differences that aren't equal to 1. However, this will return an array which is one less than the length of your input array because it finds pairwise differences up until the last element, so naturally there will be one less. As such, when you find the locations that aren't equal to 1, make sure you add 1 to the locations to account for this:
>> A=[12 13 14 15 30 31 32 33 58 59 60];
>> q = find(diff(A) ~= 1) + 1
q =
5 9
This tells us that locations 5 and 9 in your array is where the jump happens, and that's right for your example data.
However, if you want to find the locations before the jump happens, such as in your code, don't add 1 to the result:
>> q = find(diff(A) ~= 1)
q =
4 8

how to take diffrence between cell array and simple integer array in matlab?

i have extracted 23 sentences from a text file which are divided and shown in separate line each sentence is given a number in ascending order {1,2,3,...}, code i used for this is as follows:
sentences = regexp(F,'\S.*?[\.\!\?]','match')
char(sentences)
now i did some processing and got filtered answer which shows a subset of sentences as shown below:
result = 1 4 5 9 11 14 16 17
the code i used for result is as follows:
result = unique([OccursTogether{:}]);
display(result)
now what i want to do is to show the sentences that are not present in the result variable for example the result i need is as follows:
result2 = 2 3 6 7 8 10 12 13 15 18 19 20 21 22 23
remember sentences is [1*N] cell where as result is simple array saving integers.
The function you are looking for is setdiff:
%// Create an array containing the indices of all the sentences
AllSentences = 1:23;
%// Indices of sentences present
result = [1 4 5 9 11 14 16 17]
%// And not present
NotPresent = setdiff(AllSentences,result)
NotPresent =
Columns 1 through 13
2 3 6 7 8 10 12 13 15 18 19 20 21
Columns 14 through 15
22 23
I'm not sure to understand what is a cell array and what is not, but for cell arrays you can convert them to numeric arrays using cell2mat and apply the same methodology.
Eg:
AllSentences = {1:23};
NotPresent = setdiff(cell2mat(AllSentences),result)

Importing text files with comments in MATLAB

Is there any character or character combination that MATLAB interprets as comments, when importing data from text files? Being that when it detects it at the beginning of a line, will know all the line is to ignore?
I have a set of points in a file that look like this:
And as you can see he doesn't seem to understand them very well. Is there anything other than // I could use that MATLAB knows it's to ignore?
Thanks!
Actually, your data is not consistent, as you must have the same number of column for each line.
1)
Apart from that, using '%' as comments will be correctly recognized by importdata:
file.dat
%12 31
12 32
32 22
%abc
13 33
31 33
%ldddd
77 7
66 6
%33 33
12 31
31 23
matlab
data = importdata('file.dat')
2)
Otherwise use textscan to specify arbitrary comment symbols:
file2.dat
//12 31
12 32
32 22
//abc
13 33
31 33
//ldddd
77 7
66 6
//33 33
12 31
31 23
matlab
fid = fopen('file2.dat');
data = textscan(fid, '%f %f', 'CommentStyle','//', 'CollectOutput',true);
data = cell2mat(data);
fclose(fid);
If you use the function textscan, you can set the CommentStyle parameter to // or %. Try something like this:
fid = fopen('myfile.txt');
iRow = 1;
while (~feof(fid))
myData(iRow,:) = textscan(fid,'%f %f\n','CommentStyle','//');
iRow = iRow + 1;
end
fclose(fid);
That will work if there are two numbers per line. I notice in your examples the number of numbers per line varies. There are some lines with only one number. Is this representative of your data? You'll have to handle this differently if there isn't a uniform number of columns in each row.
Have you tried %, the default comment character in MATLAB?
As Amro pointed out, if you use importdata this will work.

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