Suppose I have a char variable in Matlab like this:
x = 'hello my name $ is Sean $ Daley.';
I want to replace the first '$' with the symbol '&', and the second '$' with the symbol '#'.
Furthermore, if I have a more complicated char such that pairs of '$' repeat many times, I want to repeat the same pattern. So the following:
y = 'hello $ my $ name is $ Sean $ Daley $.$.';
would be transformed into:
'hello & my # name is & Sean # Daley &.#.'
I have tried coding this manually via for loops and while loops, but the code is just so ugly. Are there any simple functions that I can use?
Since you're dealing with single characters and non-nested pairs of flags, you can easily do this with a simple call to find and some indexed replacement:
y = 'hello $ my $ name is $ Sean $ Daley $.$.';
index = find(y == '$');
y(index(1:2:end)) = '&';
y(index(2:2:end)) = '#';
And the result:
y =
'hello & my # name is & Sean # Daley &.#.'
I have a file with multiple lines; but a specific line contains tons of information, with several repeated expressions. I'm trying to extract some specific values. I first tried some commands with sed, for instance, but with no success. So, I was wondering if you could give me some insights.
So, here you have one fraction of the unique line of the given document I mentioned:
[...]6[&length_range={0.19
[... a lot of more information here in between ...]
0.01},habitat.set.prob={0.01,0.03,0.56,0.01,0.01,0.34,0.01,0.01,0.01},DLOOP.rate_median=0.04131395026396427,length=
[...]
10[&length_range={0.19
[... a lot of more information here in between ...]
0.01},habitat.set.prob={0.21,0.33,0.56,0.01,0.01,0.33,0.01,0.01,0.61},DLOOP.rate_median=0.04131395026396427,length=
[...]
My aim here is first to extract all the values that is between the brackets, after "habitat.set.prob={". and put them in a single line in a text file.
Also, it would be important to extract the numbers that appears just before the expression "[&length_range=]", which in this case are "6" and "10". They are the label of the set of numbers after "prob={"
So the set of numbers I want to extract always appears between "habitat.set.prob={" and "},DLOOP.rate_median", while the other number (the label) is always rigth before "[&length_range="; but what is before the label is not the same expression; actually it is a random number.
The goal then is end up with a file with the following characteristcs:
6 0.21,0.33,0.56,0.01,0.01,0.33,0.01,0.01,0.61
10 0.21,0.33,0.56,0.01,0.01,0.33,0.01,0.01,0.61
and so on …
What do you think? Is this possible?
I started with this very basic command at least to try to extract the set of numbers, but it didn't work
sed -n "/habitat.set.prob={/,/},DLOOP.rate_median=/ p"
| Well... I got some improvement.
I was able to get the values at least:
awk '{gsub("habitat.set.prob={","\n");printf"%s",$0}' filename | awk -F'},' '{print $1"}"}' | grep -iv "TREE" > stats.txt
|
Many thanks in advance.
Cheers,
Luiz
Something like that:
sed -rn '/.*[0-9]+\[&length_range=\{/,/habitat.set.prob=\{/{s/.*\b([0-9]+)\[&length_range.*/\1/p; s/.*habitat.set.prob=\{([^D]+)\},DLOOP.rate.*/\1/p}' habitat
6
0.01,0.03,0.56,0.01,0.01,0.34,0.01,0.01,0.01
10
0.21,0.33,0.56,0.01,0.01,0.33,0.01,0.01,0.61
The first part '/.a./,/.b./' searches from pattern a to b, distributed over multiple lines. The -n told sed to do non-printing as default.
In '/.a./,/.b./{s/.c./.d./p; s/.e./.f./p}'
there are two substitution commands with p=print in curly braces.
I am not sure if you really digged a little, so not providing the complete answer, but let's hope this would help you:
for the first part: getting the no(which you call as label) you didn't mention if there is any specific pattern, so try this (data is the file which contains the actual input) - you need to work on how to get the number and tweak the RE a bit
sed -n 's/.*\([0-9][0-9]*\).*length_range.*/\1/p' data
For the other part which gives the numericals between habitat and DLOOP:
sed -n 's/.*habitat.set.prob=\(.*\),DLOOP.*/\1/pg' data | tr '{' ' ' | tr '}' ' '
Now, try to take this as a starter and work on your output to get your desired result!
To explain a bit:
In the first section - I am trying to capture the numericals between anything(.*) and (.*)length_range [you can escape the character [ and & by using \ in front of them]
In the second section: I am capturing pattern in between habitat.set.prob and DLOOP and then doin a tr to remove the brackets.
#include <iostream>
using namespace std;
int main()
{
string p = "1:2:3:4"; //input your string
int arr[4] = {}; //create a new empty integer array to put the integers in it
for(int i=0, j=0; i <p.length(); i++){//loop on the string to extract integers
if( p[i] == ':'){continue;}//if the value = ':' skip it and continue
arr[j]=(int)p[i]-48;j++;//put the integer in the array we created
}
cout << "String={"<<arr[0]<<" "<<arr[1]<<" "<<arr[2]<<" "<<arr[3]<<"}";//print the array
return 0;
}
I'd like to have a function generate(n) that generates the first n lowercase characters of the alphabet appended in a string (therefore: 1<=n<=26)
For example:
generate(3) --> 'abc'
generate(5) --> 'abcde'
generate(9) --> 'abcdefghi'
I'm new to Matlab and I'd be happy if someone could show me an approach of how to write the function. For sure this will involve doing arithmetic with the ASCII-codes of the characters - but I've no idea how to do this and which types that Matlab provides to do this.
I would rely on ASCII codes for this. You can convert an integer to a character using char.
So for example if we want an "e", we could look up the ASCII code for "e" (101) and write:
char(101)
'e'
This also works for arrays:
char([101, 102])
'ef'
The nice thing in your case is that in ASCII, the lowercase letters are all the numbers between 97 ("a") and 122 ("z"). Thus the following code works by taking ASCII "a" (97) and creating an array of length n starting at 97. These numbers are then converted using char to strings. As an added bonus, the version below ensures that the array can only go to 122 (ASCII for "z").
function output = generate(n)
output = char(97:min(96 + n, 122));
end
Note: For the upper limit we use 96 + n because if n were 1, then we want 97:97 rather than 97:98 as the second would return "ab". This could be written as 97:(97 + n - 1) but the way I've written it, I've simply pulled the "-1" into the constant.
You could also make this a simple anonymous function.
generate = #(n)char(97:min(96 + n, 122));
generate(3)
'abc'
To write the most portable and robust code, I would probably not want those hard-coded ASCII codes, so I would use something like the following:
output = 'a':char(min('a' + n - 1, 'z'));
...or, you can just generate the entire alphabet and take the part you want:
function str = generate(n)
alphabet = 'a':'z';
str = alphabet(1:n);
end
Note that this will fail with an index out of bounds error for n > 26, so you might want to check for that.
You can use the char built-in function which converts an interger value (or array) into a character array.
EDIT
Bug fixed (ref. Suever's comment)
function [str]=generate(n)
a=97;
% str=char(a:a+n)
str=char(a:a+n-1)
Hope this helps.
Qapla'
This may be a very simple task for many but I could not find anything appropriate for me.
I have a file name: filenm_A006.2011.269.10.47.G25_2010
I want to separate all its parts (separated by . and _) to use them separately. How can I do it with simple matlab commands?
Kind Regards,
Mushi
I recommend regexp:
fname = 'filenm_A006.2011.269.10.47.G25_2010';
parts = regexp(fname, '[^_.]+', 'match');
parts =
'filenm' 'A006' '2011' '269' '10' '47' 'G25' '2010'
You can now refer to parts{1} through parts{8} for the pieces. Explanation: the regexp pattern [^_.] means all characters not equal to _ or ., and the + means you want groups of at least 1 character. Then 'match' asks the regexp function to return a cell array of the strings of all the matches of that pattern. There are other regexp modes; for example, the indices of each piece of the file.
Use the command
strsplit.
cellArrayOfParts = strsplit(fileName,{'.' '_'});
You can use strsplit to split it:
strsplit('filenm_A006.2011.269.10.47.G25_2010',{'_','.'})
ans =
'filenm' 'A006' '2011' '269' '10' '47' 'G25' '2010'
Another option is to use regexp, like Peter suggested.
I am trying to add '\' before all special characters in a string in MATLAB, could anyone please help me out. Here is the example:
tStr = 'Hi, I'm a Big (Not So Big) MATLAB addict; Since my school days!';
I want this string to be changed to:
'Hi\, I\'m a Big \(Not so Big \) MATLAB addict\; Since my school days\!'
The escape character in Matlab is the single quote ('), not the backslash (\), like in C language. Thus, your string must be like this:
tStr = 'Hi\, I\''m a Big (Not so Big ) MATLAB addict\; Since my school days!'
I took the list of special charecters defined on the Mathworks webpage to do this:
special = '[]{}()=''.().....,;:%%{%}!#';
tStr = 'Hi, I''m a Big (Not So Big) MATLAB addict; Since my school days!';
outStr = '';
for l = tStr
if (length(find(special == l)) > 0)
outStr = [outStr, '\', l];
else
outStr = [outStr, l];
end
end
which will automatically add those \s. You do need to use two single quotes ('') in place of the apostrophe in your input string. If tStr is obtained with the function input(), or something similar, this will procedure will still work.
Edited:
Or using regular expressions:
regexprep(tStr,'([[\]{}()=''.(),;:%%{%}!#])','\\$1')