# Find nearest value to specific number

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Jens Keijser on 5 Jan 2018
Commented: Nicolas Hofer on 8 Oct 2021
Hello, I have an array with 20 values of steps per minute. I already know that the perfect outcome of one of these values is 33spm. But unfortunately 33spm is not in the array 34.8 is which is the closest to 33. What is the code to find the value closest to 33?
ClosestValue = 34.8

Birdman on 5 Jan 2018
Edited: Birdman on 5 Jan 2018
Try the following approach:
a=[34.8 31 29 26.7 39.5];%dummy data
n=33;
[val,idx]=min(abs(a-n));
minVal=a(idx)
Edit after Jan's warning(multiple values)
a=[34.8 31.2 29 26.7 39.5];%dummy data
n=33;
[~,~,idx]=unique(round(abs(a-n)),'stable');
minVal=a(idx==1)
Jon Martínez Rico on 27 May 2021
Yeah, I did it @Jan. It was just to check if I was missing something.

Walter Roberson on 5 Jan 2018
Use interp1 with 'nearest'
Or since the vector is small abs() the difference between the probe and the fixed values and min() that and take the second output of min() and use that to index the fixed values. This is not as convenient as interp1 but should be faster

Atique Barudgar on 8 Nov 2019
I am not clear how Birdman SIr's answer came
when idx =1
then how a(idx)=34.8
I didnt got how and what is idx
Nicolas Hofer on 8 Oct 2021
idx stand for index. search for indexing in matlab for further explanation