rounding elements in array to nearest 0.25

i need to round off some numbers to nearest quarter , with an option to round up or round down to nearest quarter

for e.g. For an array for (5,1) with following values

1373.698
1385.024
1394.82
1400.436
1396.532

output for rounding up to closest 0.25 will result in

1373.75
1385.25
1395.00
1400.50
1396.75

output for rounding down to closest 0.25 will be

1373.50
1385.00
1394.75
1400.25
1396.50

I am not sure how to create such a function which gives this output, please help .

[Tod Wood]

B=[3;4;6;9]*29.17658137; B_round_25=round(4*B)/4;

Answer 1

[Friedrich]

Hi,

I think you are looking for:

in = [1373.698
1385.024
1394.82
1400.436
1396.532];

%round up
up = floor(in) + ceil( (in-floor(in))/0.25) * 0.25

%round down

down = floor(in) + floor( (in-floor(in))/0.25) * 0.25

[Srinivas]

Thanks :)

[Andrei Bobrov]

bsxfun(@plus,fix(in)+floor(rem(in,1)/.25)*.25,[0 .25])

Answer 2

[Walter Roberson]

The previous answers look more complex than needed

%round up
up = ceil(in * 4) / 4;

%round down
 down = floor(in * 4) / 4;

[Andrei Bobrov]

+1

[SL]

Can you make this a single function, please? - - It would be then a complete answer to the question, at least for me. I extended my case here https://se.mathworks.com/matlabcentral/answers/309097-how-to-round-up-to-closest-0-0-or-0-5-in-array

Answer 3

[Anders Tagmose Lundsfryd]

If you want to round to the nearest 0.25 both up and down, then do:

%roudn to nearest 0.25
updown = round(in * 4)/4;

[Matthias Schneider]

works perfect