How to make a string from byte subarray? [duplicate] - arrays

This question already has answers here:
How to get subslices?
(1 answer)
How do I convert a Vector of bytes (u8) to a string?
(5 answers)
Closed 1 year ago.
In Rust, given a string and a start and end byte offset – or, since it is possible to view a string as an array of bytes, a byte array and a start and end offset – what's the most efficient/idiomatic way to make another string from that slice?
I've got as far as finding String::from_utf8 which will take an entire byte array; is there an alternative function that can take a slice of a byte array? Or, is there a function that can extract part of a byte array, suitable for feeding as input to the above function? Or some other way to achieve the same goal?

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Fortran operations on multidimensional arrays - sum example [duplicate]

This question already has answers here:
Sum of a two dimensional array
(1 answer)
sum only on certain dimension
(1 answer)
Closed 4 years ago.
I am trying to figure how to do simple algebraic operations on a subset of elements in a multidimensional array and assign the result to another array with the same dimensions.
program hello
IMPLICIT NONE
REAL,DIMENSION(10,10,2,1) :: tmp1=2
REAL,DIMENSION(10,10,2,1) :: tmp2=1
INTEGER,DIMENSION(2) :: myind=(/1,2/)
This operations returns only one value
Print *, sum(tmp1(:,:,itree,:))
While this returns the correct results, however I would expect the same result than the second operation, maybe I am thinking in the R way.
Print *, tmp1(:,:,1,:)+tmp1(:,:,2,:)
end program Hello
How do I achieve the result of the second operation and assign it to another multidimensional array? Imagine my index is large so I can't type out each single term in the operation.

Ruby: Compare if array contains other array [duplicate]

This question already has answers here:
How to determine if one array contains all elements of another array
(8 answers)
Closed 4 years ago.
how can i compare if an array of strings contains a smaller array of strings in Ruby?
e.g.
a=["1","2","3","4","5"]
b=["2","3"]
now i want to check if a contains b and get true/false
Thanks.
The most common approach would be to
(b - a).empty?
It has issues with unique elements, though. To detect whether a includes all elements from b, one should:
a_copy = a.dup
b.all? { |e| a_copy.delete e }
# or
b.all?(&a_copy.method(:delete))

Creating a large 2D array? [duplicate]

This question already has answers here:
Why int array[1000][1000] is memory issue in C program? [duplicate]
(1 answer)
Getting a stack overflow exception when declaring a large array
(8 answers)
Closed 5 years ago.
I'm using a pretty simple 2D array to store values (it's part of a mandelbrot set program).
int toBeWritten[xres][yres]; // xres and yres are calculated based on command line arguments
The 2D array works fine until my numbers get larger.
These, for example, work:
int toBeWritten[1024][1160];
int toBeWritten[2048][2321];
But when the size of the array grows to this:
int toBeWritten[4092][4637]; // the size I start getting seg faults
int toBeWritten[8192][9284]; // the largest size I want to get to
I get a seg fault if I try and access this array at any point after creating it.
Is it simply too big? Am I not allocating memory correctly?
If I can't make a 2D array this large, how could I store the values instead?
Thanks for any help!

force length of int from a sensor [duplicate]

This question already has answers here:
Printing leading 0's in C
(11 answers)
Closed 6 years ago.
I get data from a sensor in int type but the data range from 0 to 999.
I need a simple way for the var to always be the same length.
Like if I get 123 I don't need to change it but if it's 43 I need it to be 043.
Is there a simple way to do that?
Thanks.
Try with:
printf("%03d", var);

How to retrieve specific index value from web_reg_save_param arrray [duplicate]

This question already has answers here:
LoadRunner web_reg_save_param, ord=all, paramName_count issues
(4 answers)
Closed 6 years ago.
I am using the web param function to retreive certain values. I want to get the value of a specific index from the array item and store it in a parameter to be used in a web_link call.
char * tempVal;
web_reg_save_param("dynArray","LB=/EmployeeProfile/","RB=\">","ORD=ALL",LAST);
tempVal = "{dynArray_2}";
There is no error for the above statements but when accessing tempVal it is giving error
vuser_init.c(143): web_link("emp") started [MsgId: MMSG-26355]
vuser_init.c(143): Warning: The string 'tempVal' with parameter delimiters is not a parameter.
vuser_init.c(143): Error -27995: Requested link ("Text={tempVal}") not found [MsgId: MERR-27995]
You have a problem which is C language based. You cannot simply equate two items as you have done.
take a look at the strcpy() function combined with lr_eval_string()
strcpy (destination_C_variable, lr_eval_string( "{LoadRunner_source_variable}" ) );

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